Malaysia
Application of Risk Assessment Approach on a Hydrogen Station
Sep 2013
Publication
An accident modelling approach is used to assess the safety of a hydrogen station as part of a ground transportation network. The method incorporates prevention barriers associated to human factors management and organizational failures in a risk assessment framework. Failure probabilities of these barriers and end-states events are predicted using Fault Tree Analysis and Event Tree Analysis respectively. Results from the case study considered revealed the capability of the proposed method in estimating the likelihood of various outcomes as well as predicting the future probability. In addition the scheme offers opportunity to provide dynamic adjustment by updating the failure probability with actual plant data. Results from the analysis can be used to plan maintenance and management of change as required by the plant condition.
A Comparison of Alternative Fuels for Shipping in Terms of Lifecycle Energy and Cost
Dec 2021
Publication
Decarbonization of the shipping sector is inevitable and can be made by transitioning into low‐ or zero‐carbon marine fuels. This paper reviews 22 potential pathways including conventional Heavy Fuel Oil (HFO) marine fuel as a reference case “blue” alternative fuel produced from natural gas and “green” fuels produced from biomass and solar energy. Carbon capture technology (CCS) is installed for fossil fuels (HFO and liquefied natural gas (LNG)). The pathways are compared in terms of quantifiable parameters including (i) fuel mass (ii) fuel volume (iii) life cycle (Well‐To‐ Wake—WTW) energy intensity (iv) WTW cost (v) WTW greenhouse gas (GHG) emission and (vi) non‐GHG emissions estimated from the literature and ASPEN HYSYS modelling. From an energy perspective renewable electricity with battery technology is the most efficient route albeit still impractical for long‐distance shipping due to the low energy density of today’s batteries. The next best is fossil fuels with CCS (assuming 90% removal efficiency) which also happens to be the lowest cost solution although the long‐term storage and utilization of CO2 are still unresolved. Biofuels offer a good compromise in terms of cost availability and technology readiness level (TRL); however the non‐GHG emissions are not eliminated. Hydrogen and ammonia are among the worst in terms of overall energy and cost needed and may also need NOx clean‐up measures. Methanol from LNG needs CCS for decarbonization while methanol from biomass does not and also seems to be a good candidate in terms of energy financial cost and TRL. The present analysis consistently compares the various options and is useful for stakeholders involved in shipping decarbonization.
Hydrogen Energy Demand Growth Prediction and Assessment (2021–2050) Using a System Thinking and System Dynamics Approach
Jan 2022
Publication
Adoption of hydrogen energy as an alternative to fossil fuels could be a major step towards decarbonising and fulfilling the needs of the energy sector. Hydrogen can be an ideal alternative for many fields compared with other alternatives. However there are many potential environmental challenges that are not limited to production and distribution systems but they also focus on how hydrogen is used through fuel cells and combustion pathways. The use of hydrogen has received little attention in research and policy which may explain the widely claimed belief that nothing but water is released as a by-product when hydrogen energy is used. We adopt systems thinking and system dynamics approaches to construct a conceptual model for hydrogen energy with a special focus on the pathways of hydrogen use to assess the potential unintended consequences and possible interventions; to highlight the possible growth of hydrogen energy by 2050. The results indicate that the combustion pathway may increase the risk of the adoption of hydrogen as a combustion fuel as it produces NOx which is a key air pollutant that causes environmental deterioration which may limit the application of a combustion pathway if no intervention is made. The results indicate that the potential range of global hydrogen demand is rising ranging from 73 to 158 Mt in 2030 73 to 300 Mt in 2040 and 73 to 568 Mt in 2050 depending on the scenario presented.
Cost Effective Inherent Safety Index for Polymer Electrolyte Membrane Fuel Cell Systems
Sep 2013
Publication
There have been many indices available in the process industries to describe rank or quantify hazards to people properties and environments. Most of the developed methods were meant to be applied to large scale and complex systems of process industries. Development of a swift and simple inherent safety index method which is relevant to small scale less complex membrane fuel cell system particularly the one in which to be applied during an early design stage is essential as an alternative to current comprehensive and yet time-consuming indices. In this work a modified version of PIIS modified prototype index for inherent safety (m-PIIS) was developed with the objectives of identifying indicating and estimating inherent safety of fuel cell system at an early design stage. The developed index was tested at four proton exchange membrane (PEM) fuel cell systems namely high pressure PEMFC system low pressure PEMFC system LH2 PEMFC system and on-board Me-OH PEMFC system. The developed index was also benchmarked against the original PIIS and ISI using the published results for the selection of process routes in MMA production. Results have indicated that m-PIIS has strong positive relationship with PIIS and ISI on most of the reaction step in MMA with the most significant are the C4 TBA and C3 reaction steps. Other reaction steps such as C2/MP C2/PA and ACH showed a strong positive relationship as well.
Membrane-Based Electrolysis for Hydrogen Production: A Review
Oct 2021
Publication
Hydrogen is a zero-carbon footprint energy source with high energy density that could be the basis of future energy systems. Membrane-based water electrolysis is one means by which to produce high-purity and sustainable hydrogen. It is important that the scientific community focus on developing electrolytic hydrogen systems which match available energy sources. In this review various types of water splitting technologies and membrane selection for electrolyzers are discussed. We highlight the basic principles recent studies and achievements in membrane-based electrolysis for hydrogen production. Previously the NafionTM membrane was the gold standard for PEM electrolyzers but today cheaper and more effective membranes are favored. In this paper CuCl–HCl electrolysis and its operating parameters are summarized. Additionally a summary is presented of hydrogen production by water splitting including a discussion of the advantages disadvantages and efficiencies of the relevant technologies. Nonetheless the development of cost-effective and efficient hydrogen production technologies requires a significant amount of study especially in terms of optimizing the operation parameters affecting the hydrogen output. Therefore herein we address the challenges prospects and future trends in this field of research and make critical suggestions regarding the implementation of comprehensive membrane-based electrolytic systems.
Influence of Pressure, Temperature and Organic Surface Concentration on Hydrogen Wettability of Caprock; Implications for Hydrogen Geo-storage
Sep 2021
Publication
Hydrogen (H2) as a cleaner fuel has been suggested as a viable method of achieving the decarbonization objectives and meeting increasing global energy demand. However successful implementation of a full-scale hydrogen economy requires large-scale hydrogen storage (as hydrogen is highly compressible). A potential solution to this challenge is injecting hydrogen into geologic formations from where it can be withdrawn again at later stages for utilization purposes. The geostorage capacity of a porous formation is a function of its wetting characteristics which strongly influence residual saturations fluid flow rate of injection rate of withdrawal and containment security. However literature severely lacks information on hydrogen wettability in realistic geological and caprock formations which contain organic matter (due to the prevailing reducing atmosphere). We therefore measured advancing (θa) and receding (θr) contact angles of mica substrates at various representative thermo-physical conditions (pressures 0.1-25 MPa temperatures 308–343 K and stearic acid concentrations of 10−9 - 10−2 mol/L). The mica exhibited an increasing tendency to become weakly water-wet at higher temperatures lower pressures and very low stearic acid concentration. However it turned intermediate-wet at higher pressures lower temperatures and increasing stearic acid concentrations. The study suggests that the structural H2 trapping capacities in geological formations and sealing potentials of caprock highly depend on the specific thermo-physical condition. Thus this novel data provides a significant advancement in literature and will aid in the implementation of hydrogen geo-storage at an industrial scale.
Integrated Energy System Powered a Building in Sharjah Emirates in the United Arab Emirates
Jan 2023
Publication
In this study a green hydrogen system was studied to provide electricity for an office building in the Sharjah emirate in the United Arab Emirates. Using a solar PV a fuel cell a diesel generator and battery energy storage; a hybrid green hydrogen energy system was compared to a standard hybrid system (Solar PV a diesel generator and battery energy storage). The results show that both systems adequately provided the power needed for the load of the office building. The cost of the energy for both the basic and green hydrogen energy systems was 0.305 USD/kWh and 0.313 USD/kWh respectively. The cost of the energy for both systems is very similar even though the capital cost of the green hydrogen energy system was the highest value; however the replacement and operational costs of the basic system were higher in comparison to the green hydrogen energy system. Moreover the impact of the basic system in terms of the carbon footprint was more significant when compared with the green hydrogen system. The reduction in carbon dioxide was a 4.6 ratio when compared with the basic system.
Sustainable Aviation—Hydrogen Is the Future
Jan 2022
Publication
As the global search for new methods to combat global warming and climate change continues renewable fuels and hydrogen have emerged as saviours for environmentally polluting industries such as aviation. Sustainable aviation is the goal of the aviation industry today. There is increasing interest in achieving carbon-neutral flight to combat global warming. Hydrogen has proven to be a suitable alternative fuel. It is abundant clean and produces no carbon emissions but only water after use which has the potential to cool the environment. This paper traces the historical growth and future of the aviation and aerospace industry. It examines how hydrogen can be used in the air and on the ground to lower the aviation industry’s impact on the environment. In addition while aircraft are an essential part of the aviation industry other support services add to the overall impact on the environment. Hydrogen can be used to fuel the energy needs of these services. However for hydrogen technology to be accepted and implemented other issues such as government policy education and employability must be addressed. Improvement in the performance and emissions of hydrogen as an alternative energy and fuel has grown in the last decade. However other issues such as the storage and cost and the entire value chain require significant work for hydrogen to be implemented. The international community’s alternative renewable energy and hydrogen roadmaps can provide a long-term blueprint for developing the alternative energy industry. This will inform the private and public sectors so that the industry can adjust its plan accordingly.
Combustion Characteristics of Diesel-hydrogen Dual Fuel Engine at Low Load
May 2013
Publication
In the present study hydrogen utilization as diesel engine fuel at low load operation was investigated. Hydrogen cannot be used directly in a diesel engine due to its auto ignition temperature higher than that of diesel fuel. One alternative method is to use hydrogen in enrichment or induction. To investigate the combustion characteristics of this dual fuel engine a single cylinder diesel research engine was converted to utilize hydrogen as fuel. Hydrogen was introduced to the intake manifold using a mixer before entering the combustion chamber. The engine was run at a constant speed of 2000 rpm and 10 Nm load. Hydrogen was introduced at the flow rate of 21.4 36.2 and 49.6 liter/minute. Specific energy consumption indicated efficiency and cylinder pressure were investigated. At this low load the hydrogen enrichment reduced the cylinder peak pressure and the engine efficiency. The reaction progress variable and combustion rate of reaction were slower as shown by the CFD calculation.
Biomass Steam Gasification with In-Situ CO2 Capture for Enriched Hydrogen Gas Production: A Reaction Kinetics Modelling Approach
Aug 2010
Publication
Due to energy and environmental issues hydrogen has become a more attractive clean fuel. Furthermore there is high interest in producing hydrogen from biomass with a view to sustainability. The thermochemical process for hydrogen production i.e. gasification is the focus of this work. This paper discusses the mathematical modeling of hydrogen production process via biomass steam gasification with calcium oxide as sorbent in a gasifier. A modelling framework consisting of kinetics models for char gasification methanation Boudouard methane reforming water gas shift and carbonation reactions to represent the gasification and CO2 adsorption in the gasifier is developed and implemented in MATLAB. The scope of the work includes an investigation of the influence of the temperature steam/biomass ratio and sorbent/biomass ratio on the amount of hydrogen produced product gas compositions and carbon conversion. The importance of different reactions involved in the process is also discussed. It is observed that hydrogen production and carbon conversion increase with increasing temperature and steam/biomass ratio. The model predicts a maximum hydrogen mole fraction in the product gas of 0.81 occurring at 950 K steam/biomass ratio of 3.0 and sorbent/biomass ratio of 1.0. In addition at sorbent/biomass ratio of 1.52 purity of H2 can be increased to 0.98 mole fraction with all CO2 present in the system adsorbed.
An Integrated Hydrogen Fuel Cell to Distribution Network System: Challenging and Opportunity for D-STATCOM
Oct 2021
Publication
The electric power industry sector has become increasingly aware of how counterproductive voltage sag affects distribution network systems (DNS). The voltage sag backfires disastrously at the demand load side and affects equipment in DNS. To settle the voltage sag issue this paper achieved its primary purpose to mitigate the voltage sag based on integrating a hydrogen fuel cell (HFC) with the DNS using a distribution static synchronous compensator (D-STATCOM) system. Besides this paper discusses the challenges and opportunities of D-STATCOM in DNS. In this paper using HFC is well-designed modeled and simulated to mitigate the voltage sag in DNS with a positive impact on the environment and an immediate response to the issue of the injection of voltage. Furthermore this modeling and controller are particularly suitable in terms of cost-effectiveness as well as reliability based on the adaptive network fuzzy inference system (ANFIS) fuzzy logic system (FLC) and proportional–integral (P-I). The effectiveness of the MATLAB simulation is confirmed by implementing the system and carrying out a DNS connection obtaining efficiencies over 94.5% at three-phase fault for values of injection voltage in HFC D-STATCOM using a P-I controller. Moreover the HFC D-STATCOM using FLC proved capable of supporting the network by 97.00%. The HFC D-STATCOM based ANFIS proved capable of supporting the network by 98.00% in the DNS.
An Overview of Economic Analysis and Environmental Impacts of Natural Gas Conversion Technologies
Dec 2020
Publication
This study presents an overview of the economic analysis and environmental impact of natural gas conversion technologies. Published articles related to economic analysis and environmental impact of natural gas conversion technologies were reviewed and discussed. The economic analysis revealed that the capital and the operating expenditure of each of the conversion process is strongly dependent on the sophistication of the technical designs. The emerging technologies are yet to be economically viable compared to the well-established steam reforming process. However appropriate design modifications could significantly reduce the operating expenditure and enhance the economic feasibility of the process. The environmental analysis revealed that emerging technologies such as carbon dioxide (CO2) reforming and the thermal decomposition of natural gas offer advantages of lower CO2 emissions and total environmental impact compared to the well-established steam reforming process. Appropriate design modifications such as steam reforming with carbon capture storage and utilization the use of an optimized catalyst in thermal decomposition and the use of solar concentrators for heating instead of fossil fuel were found to significantly reduced the CO2 emissions of the processes. There was a dearth of literature on the economic analysis and environmental impact of photocatalytic and biochemical conversion processes which calls for increased research attention that could facilitate a comparative analysis with the thermochemical processes.
Advanced Hydrogen Storage of the Mg–Na–Al System: A Review
May 2021
Publication
A solid-state storage system is the most practical option for hydrogen because it is more convenient and safer. Metal hydrides especially MgH2 are the most promising materials that offer high gravimetric capacity and good reversibility. However the practical application of MgH2 is restricted by slow sorption kinetics and high stability of thermodynamic properties. Hydrogen storage performance of MgH2 was enhanced by introducing the Mg–Na–Al system that destabilises MgH2 with NaAlH4. The Mg–Na–Al system has superior performance compared to that of unary MgH2 and NaAlH4. To boost the performance of the Mg–Na–Al system the ball milling method and the addition of a catalyst were introduced. The Mg–Na–Al system resulted in a low onset decomposition temperature superior cyclability and enhanced kinetics performances. The Al12Mg17 and NaMgH3 that formed in situ during the dehydrogenation process modify the reaction pathway of the Mg–Na–Al system and alter the thermodynamic properties. In this paper the overview of the recent progress in hydrogen storage of the Mg–Na–Al system is detailed. The remaining challenges and future development of Mg–Na–Al system are also discussed. This paper is the first review report on hydrogen storage properties of the Mg–Na–Al system.
A Hot Syngas Purification System Integrated with Downdraft Gasification of Municipal Solid Waste
Jan 2019
Publication
Gasification of municipal solid waste (MSW) with subsequent utilization of syngas in gas engines/turbines and solid oxide fuel cells can substantially increase the power generation of waste-to-energy facilities and optimize the utilization of wastes as a sustainable energy resources. However purification of syngas to remove multiple impurities such as particulates tar HCl alkali chlorides and sulfur species is required. This study investigates the feasibility of high temperature purification of syngas from MSW gasification with the focus on catalytic tar reforming and desulfurization. Syngas produced from a downdraft fixed-bed gasifier is purified by a multi-stage system. The system comprises of a fluidized-bed catalytic tar reformer a filter for particulates and a fixed-bed reactor for dechlorination and then desulfurization with overall downward cascading of the operating temperatures throughout the system. Novel nano-structured nickel catalyst supported on alumina and regenerable Ni-Zn desulfurization sorbent loaded on honeycomb are synthesized. Complementary sampling and analysis methods are applied to quantify the impurities and determine their distribution at different stages. Experimental and thermodynamic modeling results are compared to determine the kinetic constraints in the integrated system. The hot purification system demonstrates up to 90% of tar and sulfur removal efficiency increased total syngas yield (14%) and improved cold gas efficiency (12%). The treated syngas is potentially applicable in gas engines/turbines and solid oxide fuel cells based on the dew points and concentration limits of the remaining tar compounds. Reforming of raw syngas by nickel catalyst for over 20 h on stream shows strong resistance to deactivation. Desulfurization of syngas from MSW gasification containing significantly higher proportion of carbonyl sulfide than hydrogen sulfide traces of tar and hydrogen chloride demonstrates high performance of Ni-Zn sorbents.
Renewable-based Zero-carbon Fuels for the Use of Power Generation: A Case Study in Malaysia Supported by Updated Developments Worldwide
Apr 2021
Publication
The existing combustion-centered energy mix in Malaysia has shown that replacing fossil fuels with zero-carbon alternative fuels could be a better approach to achieve the reduction of the carbon footprint of the power generation industry. In this study the potential of zero-carbon alternative fuels generated from renewable sources such as green hydrogen and green ammonia was addressed in terms of the production transport storage and utilization in Malaysia’s thermal power plants. The updated developments associated to green hydrogen and green ammonia across the globe have also been reviewed to support the existing potential in Malaysia. Though green hydrogen and green ammonia are hardly commercialized in Malaysia for the time being numerous potentialities have been identified in utilizing these fuels to achieve the zero-carbon power generation market in Malaysia. The vast and strategic location of natural gas network in Malaysia has the potential to deliver green hydrogen with minimal retrofitting required. Moreover there are active participation of Malaysia’s academic institutions in the development of water electrolysis that is the core process to convert the electricity from renewables plant into hydrogen. Malaysia also has the capacity to use its abundance of depleted gas reservoirs for the storage of green hydrogen. A large number of GT plants in Malaysia would definitely have the potential to utilize hydrogen co-firing with natural gas to minimize the amount of carbon dioxide (CO2) released. The significant number of ammonia production plants in Malaysia could provide a surplus of ammonia to be used as an alternative fuel for power plants. With regard to the energy policy in Malaysia positive acceptance of the implementation of renewable energy has been shown with the introduction of various energy policies aimed at promoting the incorporation of renewables into the energy mix. However there is still inadequate support for the implementation of alternative zero-carbon fuels in Malaysia.
Hydrogen Fuel Cells for Sustainable Energy: Development and Progress in Selected Developed Countries
Jan 2021
Publication
The sustainable development goals concept towards zero carbon emission set forth by the Paris Agreement is the foundation of decarbonisation implemented in most developed countries worldwide. One of the efforts in the decarbonisation of the environment is through hydrogen fuel cell technology. A fuel cell is an energy converter device that produces electricity via the electrochemical reaction with water as the by-product. The application of fuel cells is strongly related to the economic aspect including local and infrastructure costs making it more relevant to be implemented in a developed country. This work presents a short review of the development and progress of hydrogen fuel cells in a developed country such as Japan Germany USA Denmark and China (in transition between developing to developed status); which championed hydrogen fuel cell technology in their region.
Decommissioning Platforms to Offshore Solar System: Road to Green Hydrogen Production from Seawater
May 2023
Publication
With more than 140 offshore platforms identified in Malaysian water to be decommissioned within 10 years it is critical for the Oil and Gas operators to re-evaluate the overall decommissioning strategies for a more sustainable approach. A revision to the current decommissioning options with inclusion of green decommissioning plan to the overall decision tree will assist in accelerating sustainable decision making. Using the advantage of the available 3D modelling from Naviswork and convert to PVSyst software for solar analysis to the one of the shortlisted offshore gas complexes in Malaysia three solar powered generation scenario was evaluated with aimed to establish the best integrated system on a modified decommissioned unmanned processing platform to generate cleaner energy. Financial assessment inclusive of Levelized Cost of Electricity as well as environmental assessment for each scenario are evaluated together. From the study optimum tilt angle was determined resulted to best annual solar yield of 257MWh with performance ratio (PR) of 87% for on-grid scenario 1. Off-grid scenario 3 is used to understand the estimated green hydrogen production. A desktop investigation conducted to three (3) type of electrolysers resulted to 8.6 kg to 18 kg of green hydrogen based on the average daily solar yield produced in scenario 3. Using Proton Electron Membrane electrolyser to simulate the PV solar-to-hydrogen offshore system it is observed that 98% of annual solar fraction can be achieved with annual performance ratio of 74.5% with levelized cost of Hydrogen (LCOH) of $10.95 per kg. From financial assessment this study justifies platforms repurpose to renewable energy concept to be an attractive option since cost to decommission the identified complex was observed to be 11 times greater compared to investing for this proposed concept.
Multi-criteria Optimisation of Fermentative and Solar-driven Electrolytic Hydrogen and Electricity Supply-demand Network with Hybrid Storage System
May 2023
Publication
Harnessing renewable resources such as solar energy and biogenic waste for hydrogen production offers a path toward a carbon-neutral industrial economy. This study suggests the development of a renewable-based hydrogen and power supply facility (HPSF) that relies on fermentation and solar-driven electrolysis technologies to achieve penetration of renewable hydrogen and electricity in the industrial symbiosis. Literature studies reported that the hybrid battery-hydrogen storage system could effectively improve the sustainability and reliability of renewable energy supplies yet its application under diurnal and seasonal renewable resource variations has not been well studied. Hence this work develops a multi-criteria optimisation framework for the configuration design of the proposed HPSF that concurrently targets industrial hydrogen and electrical loads with the consideration of diurnal and seasonal renewable resource variations. Case scenarios with different storage applications are presented to evaluate the role of storage in improving economic and environmental sustainability. The results show that the application of hybrid storage with molten carbonate fuel cell (MCFC) systems is preferred from a comprehensive sustainability standpoint which improves the sustainability-weighted return-on investment metric (SWROIM) score by 4%/yr compared to HPSF without storage application. On the other hand the application of a single-battery system is the most economical solution with a return on investment (ROI) of 0.7%/yr higher than the hybrid storage approach. The research outcome could provide insights into the integration of fermentative and solar-driven electrolytic hydrogen production technologies into the industrial symbiosis to further enhance a sustainable economy.
Using the Jet Stream for Sustainable Airship and Balloon Transportation of Cargo and Hydrogen
Jul 2019
Publication
The maritime shipping sector is a major contributor to CO2 emissions and this figure is expected to rise in coming decades. With the intent of reducing emissions from this sector this research proposes the utilization of the jet stream to transport a combination of cargo and hydrogen using airships or balloons at altitudes of 10–20 km. The jet streams flow in the mid-latitudes predominantly in a west–east direction reaching an average wind speed of 165 km/h. Using this combination of high wind speeds and reliable direction hydrogen-filled airships or balloons could carry hydrogen with a lower fuel requirement and shorter travel time compared to conventional shipping. Jet streams at different altitudes in the atmosphere were used to identify the most appropriate circular routes for global airship travel. Round-the-world trips would take 16 days in the Northern Hemisphere and 14 in the Southern Hemisphere. Hydrogen transport via the jet stream due to its lower energy consumption and shorter cargo delivery time access to cities far from the coast could be a competitive alternative to maritime shipping and liquefied hydrogen tankers in the development of a sustainable future hydrogen economy.
Simulation of the Combustion Process for a CI Hydrogen Engine in an Argon-oxygen Atmosphere
May 2018
Publication
Hydrogen combustion in a noble gas atmosphere increases the combustion chamber temperature and the high specific heat ratio of the gas increases the thermal efficiency. In this study nitrogen was replaced by argon as the intake air along with pure oxygen to supply the engine. The objectives of this study are to determine the effects of different engine parameters on combustion and to analyse the emissions from hydrogen combustion in an argon-oxygen atmosphere. This research was conducted through simulations using CONVERGE 2.2.0 software and the YANMAR engine NF19SK model was used to determine the basic parameters. Changing the injector location affects the pressure and temperature in the combustion chamber. With increasing compression ratio the pressure increases more rapidly than the temperature. However combustion at high compression ratios decreases the maximum heat release rate and increases the combustion duration. Hydrogen combustion at ambient temperatures below 1200 K follows the Arrhenius equation.
A Review on Recent Progress in the Integrated Green Hydrogen Production Processes
Feb 2022
Publication
The thermochemical water‐splitting method is a promising technology for efficiently con verting renewable thermal energy sources into green hydrogen. This technique is primarily based on recirculating an active material capable of experiencing multiple reduction‐oxidation (redox) steps through an integrated cycle to convert water into separate streams of hydrogen and oxygen. The thermochemical cycles are divided into two main categories according to their operating temperatures namely low‐temperature cycles (<1100 °C) and high‐temperature cycles (<1100 °C). The copper chlorine cycle offers relatively higher efficiency and lower costs for hydrogen production among the low‐temperature processes. In contrast the zinc oxide and ferrite cycles show great potential for developing large‐scale high‐temperature cycles. Although several challenges such as energy storage capacity durability cost‐effectiveness etc. should be addressed before scaling up these technologies into commercial plants for hydrogen production. This review critically examines various aspects of the most promising thermochemical water‐splitting cycles with a particular focus on their capabilities to produce green hydrogen with high performance redox pairs stability and the technology maturity and readiness for commercial use.
A Comprehensive Review of Microbial Electrolysis Cells (MEC) Reactor Designs and Configurations for Sustainable Hydrogen Gas Production
Nov 2015
Publication
Hydrogen gas has tremendous potential as an environmentally acceptable energy carrier for vehicles. A cutting edge technology called a microbial electrolysis cell (MEC) can achieve sustainable and clean hydrogen production from a wide range of renewable biomass and wastewaters. Enhancing the hydrogen production rate and lowering the energy input are the main challenges of MEC technology. MEC reactor design is one of the crucial factors which directly influence on hydrogen and current production rate in MECs. The rector design is also a key factor to upscaling. Traditional MEC designs incorporated membranes but it was recently shown that membrane-free designs can lead to both high hydrogen recoveries and production rates. Since then multiple studies have developed reactors that operate without membranes. This review provides a brief overview of recent advances in research on scalable MEC reactor design and configurations.
Optimization and Sustainability of Gasohol/hydrogen Blends for Operative Spark Ignition Engine Utilization and Green Environment
Aug 2022
Publication
One of the many technical benefits of green diesel (GD) is its ability to be oxygenated lubricated and adopted in diesel engines without requiring hardware modifications. The inability of GD to reduce exhaust tail emissions and its poor performance in endurance tests have spurred researchers to look for new clean fuels. Improving gasohol/hydrogen blend (GHB) spark ignition is critical to its long-term viability and accurate demand forecasting. This study employed the Response Surface Methodology (RSM) to identify the appropriate GHB and engine speed (ES) for efficient performance and lower emissions in a GHB engine. The RSM model output variables included brake specific fuel consumption (BSFC) brake thermal efficiency (BTE) hydrocarbon (HC) carbon dioxide (CO2) and carbon monoxide (CO) while the input variables included ES and GHB. The Analysis of Variance-assisted RSM revealed that the most affected responses are BSFC and BTE. Based on the desirability criteria the best values for the GHB and the ES were determined to be 20% and 1500 rpm respectively while the validation between experimental and numerical results was calculated to be 4.82. As a result the RSM is a useful tool for predicting the optimal GHB and ES for optimizing spark-ignition engine characteristics and ensuring benign environment.
Review of the Effects of Fossil Fuels and the Need for a Hydrogen Fuel Cell Policy in Malaysia
Feb 2023
Publication
The world has relied on fossil fuel energy for a long time producing many adverse effects. Long-term fossil fuel dependency has increased carbon emissions and accelerated climate change. In addition fossil fuels are also depleting and will soon be very costly. Moreover the expensive national electricity grid has yet to reach rural areas and will be cut off in inundation areas. As such alternative and carbon-free hydrogen fuel cell energy is highly recommended as it solves these problems. The reviews find that (i) compared to renewable energy such as solar biomass and hydropower a fuel cell does not require expensive transmission through an energy grid and is carbon-free and hence it is a faster agent to decelerate climate change; (ii) fuel cell technologies have reached an optimum level due to the high-efficiency production of energy and they are environmentally friendly; (iii) the absence of a policy on hydrogen fuel cells will hinder investment from private companies as they are not adequately regulated. It is thus recommended that countries embarking on hydrogen fuel cell development have a specific policy in place to allow the government to fund and regulate hydrogen fuel cells in the energy generation mix. This is essential as it provides the basis for alternative energy governance development and management of a country.
Solid Oxide Fuel Cell-Based Polygeneration Systems in Residential Applications: A Review of Technology, Energy Planning and Guidelines for Optimizing the Design
Oct 2022
Publication
Solid oxide fuel cells are an emerging energy conversion technology suitable for high-temperature power generation with proper auxiliary heat. Combining SOFCs and polygeneration has produced practical applications for modern energy system designs. Even though many researchers have reviewed these systems’ technologies opportunities and challenges reviews regarding the optimal strategy for designing and operating the systems are limited. Polygeneration is more complicated than any other energy generation type due to its ability to generate many types of energy from various prime movers. Moreover integration with other applications such as vehicle charging and fueling stations increases the complication in making the system optimally serve the loads. This study elaborates on the energy planning and guidelines for designing a polygeneration system especially for residential applications. The review of polygeneration technologies also aligns with the current research trend of developing green technology for modern and smart homes in residential areas. The proposed guideline is expected to solve the complication in other applications and technologies and design the polygeneration system optimally.
Hydrogen Energy as Future of Sustainable Mobility
May 2022
Publication
Conventional fuels for vehicular applications generate hazardous pollutants which have an adverse effect on the environment. Therefore there is a high demand to shift towards environment-friendly vehicles for the present mobility sector. This paper highlights sustainable mobility and specifically sustainable transportation as a solution to reduce GHG emissions. Thus hydrogen fuel-based vehicular technologies have started blooming and have gained significance following the zero-emission policy focusing on various types of sustainable motilities and their limitations. Serving an incredible deliverance of energy by hydrogen fuel combustion engines hydrogen can revolution various transportation sectors. In this study the aspects of hydrogen as a fuel for sustainable mobility sectors have been investigated. In order to reduce the GHG (Green House Gas) emission from fossil fuel vehicles researchers have paid their focus for research and development on hydrogen fuel vehicles and proton exchange fuel cells. Also its development and progress in all mobility sectors in various countries have been scrutinized to measure the feasibility of sustainable mobility as a future. This paper is an inclusive review of hydrogen-based mobility in various sectors of transportation in particular fuel cell cars that provides information on various technologies adapted with time to add more towards perfection. When compared to electric vehicles with a 200-mile range fuel cell cars have a lower driving cost in all of the 2035 and 2050 scenarios. To stimulate the use of hydrogen as a passenger automobile fuel the cost of a hydrogen fuel cell vehicle (FCV) must be brought down to at least the same level as an electric vehicle. Compared to gasoline cars fuel cell vehicles use 43% less energy and generate 40% less CO2.
A Review on Production and Implementation of Hydrogen as a Green Fuel in Internal Combustion Engines
Nov 2022
Publication
Huge and continuously growing non-renewable energy consumption due to human daily activities is accountable for the fossil fuel source crisis in recent decades. The growing concern about the emissions from internal combustion engines also impels the development of new energy sources to replace or reduce conventional non-renewable energy usage. In this context hydrogen is found to be a promising solution in internal combustion engines to address these issues. The novelty of this review is to provide an overview of the use of hydrogen as internal combustion fuel covering the operations in both spark-ignition (SI) and compression-ignition (CI) engines. Majority of the studies had shown that hydrogen enrichment fuels marked incredible engine performance in terms of thermal efficiency fuel consumption and energy consumption. In addition reductions in exhaust emissions such as smoke soot HC CO CO2 and NOx can be achieved in both SI and CI engines with proper operating conditions. Moreover outstanding combustion behaviours were observed in both internal combustion engines with the application of hydrogen fuel. These enhancements were mainly attributed to the physico-chemical properties of hydrogen which exhibits higher calorific value and rapid flaming speed as discussed in this paper. To summarize hydrogen utilisation in the IC and SI engines aided improvements in engine performance exhaust emissions and combustion behaviours under appropriate operating conditions and minor engine modifications such as ignition system and iridium spark plug for SI engines.
Estimates of the Decarbonization Potential of Alternative Fuels for Shipping as a Function of Vessel Type, Cargo, and Voyage
Oct 2022
Publication
Fuel transition can decarbonize shipping and help meet IMO 2050 goals. In this paper HFO with CCS LNG with CCS bio-methanol biodiesel hydrogen ammonia and electricity were studied using empirical ship design models from a fleet-level perspective and at the Tank-ToWake level to assist operators technology developers and policy makers. The cargo attainment rate CAR (i.e. cargo that must be displaced due to the low-C propulsion system) the ES (i.e. TTW energy needed per ton*n.m.) the CS (economic cost per ton*n.m.) and the carbon intensity index CII (gCO2 per ton*n.m.) were calculated so that the potential of the various alternatives can be compared quantitatively as a function of different criteria. The sensitivity of CAR towards ship type fuel type cargo type and voyage distance were investigated. All ship types had similar CAR estimates which implies that considerations concerning fuel transition apply equally to all ships (cargo containership tankers). Cargo type was the most sensitive factor that made a ship either weight or volume critical indirectly impacting on the CAR of different fuels; for example a hydrogen ship is weight-critical and has 2.3% higher CAR than the reference HFO ship at 20000 nm. Voyage distance and fuel type could result in up to 48.51% and 11.75% of CAR reduction. In addition to CAR the ES CS and CII for a typical mission were calculated and it was found that HFO and LNG with CCS gave about 20% higher ES and CS than HFO and biodiesel had twice the cost while ammonia methanol and hydrogen had 3–4 times the CS of HFO and electricity about 20 times suggesting that decarbonisation of the world’s fleet will come at a large cost. As an example of including all factors in an effort to create a normalized scoring system an equal weight was allocated to each index (CAR ES CS and CII). Biodiesel achieved the highest score (80%) and was identified as the alternative with the highest potential for a deep-seagoing containership followed by ammonia hydrogen bio-methanol and CCS. Electricity has the lowest normalized score of 33%. A total of 100% CAR is achievable by all alternative fuels but with compromises in voyage distance or with refuelling. For example a battery containership carrying an equal amount of cargo as an HFO-fuelled containership can only complete 13% of the voyage distance or needs refuelling seven times to complete 10000 n.m. The results can guide decarbonization strategies at the fleet level and can help optimise emissions as a function of specific missions.
Sustainable Hydrogen Energy in Aviation - A Narrative Review
Feb 2023
Publication
In the modern world zero-carbon society has become a new buzzword of the era. Many projects have been initiated to develop alternatives not only to the environmental crisis but also to the shortage of fossil fuels. With successful projects in automobile technology hydrogen fuel is now being tested and utilized as a sustainable green fuel in the aviation sector which will lead to zero carbon emission in the future. From the mid-20th century to the early 21st numerous countries and companies have funded multimillion projects to develop hydrogen-fueled aircraft. Empirical data show positive results for various projects. Consequently large companies are investing in various innovations undertaken by researchers under their supervision. Over time the efficiency of hydrogen-fueled aircraft has improved but the lack of refueling stations large production cost and consolidated carbon market share have impeded the path of hydrogen fuel being commercialized. In addition the Unmanned Aerial Vehicle (UAV) is another important element of the Aviation industry Hydrogen started to be commonly used as an alternative fuel for heavy-duty drones using fuel cell technology. The purpose of this paper is to provide an overview of the chronological development of hydrogen-powered aircraft technology and potential aviation applications for hydrogen and fuel cell technology. Furthermore the major barriers to widespread adoption of hydrogen technology in aviation are identified as are future research opportunities.
Controlling the Pressure of Hydrogen-natural Gas Mixture in an Inclined Pipeline
Feb 2020
Publication
This paper discusses the optimal control of pressure using the zero-gradient control (ZGC) approach. It is applied for the first time in the study to control the optimal pressure of hydrogen natural gas mixture in an inclined pipeline. The solution to the flow problem is first validated with existing results using the Taylor series approximation regression analysis and the Runge-Kutta method combined. The optimal pressure is then determined using ZGC where the optimal set points are calculated without having to solve the non-linear system of equations associated with the standard optimization problem. It is shown that the mass ratio is the more effective parameter compared to the initial pressure in controlling the maximum variation of pressure in a gas pipeline.
An Overview of the Recent Advances of Additive‐Improved Mg(BH4)2 for Solid‐State Hydrogen Storage Material
Jan 2022
Publication
Recently hydrogen (H2) has emerged as a superior energy carrier that has the potential to replace fossil fuel. However storing H2 under safe and operable conditions is still a challenging process due to the current commercial method i.e. H2 storage in a pressurised and liquified state which requires extremely high pressure and extremely low temperature. To solve this problem re‐ search on solid‐state H2 storage materials is being actively conducted. Among the solid‐state H2 storage materials borohydride is a potential candidate for H2 storage owing to its high gravimetric capacity (majority borohydride materials release >10 wt% of H2). Mg(BH4)2 which is included in the borohydride family shows promise as a good H2 storage material owing to its high gravimetric capacity (14.9 wt%). However its practical application is hindered by high thermal decomposition temperature (above 300 °C) slow sorption kinetics and poor reversibility. Currently the general research on the use of additives to enhance the H2 storage performance of Mg(BH4)2 is still under investigation. This article reviews the latest research on additive‐enhanced Mg(BH4)2 and its impact on the H2 storage performance. The future prospect and challenges in the development of additive‐ enhanced Mg(BH4)2 are also discussed in this review paper. To the best of our knowledge this is the first systematic review paper that focuses on the additive‐enhanced Mg(BH4)2 for solid‐state H2 storage.
Outlook of Fermentative Hydrogen Production Techniques: An Overview of Dark, Photo and Integrated Dark-photo Fermentative Approach to Biomass
Jan 2019
Publication
Biomass can be a sustainable choice for bioenergy production worldwide. Biohydrogen production using fermentative conversion of biomass has gained great interest during the last decade. Besides being an efficient transportation fuel biohydrogen can also be also be a low-carbon source of heat and electricity. Microbes assisted conversion (bioconversion) can be take place either in presence or absence of light. This is called photofermentation or dark-fermentation respectively. This review provides an overview of approaches of fermentative hydrogen production. This includes: dark photo and integrated fermentative modes of hydrogen production; the molecular basis behind its production and diverse range of its applicability industrially. Mechanistic understanding of the metabolic pathways involved in biomass-based fermentative hydrogen production are also reviewed.
Hydrogen Energy Vision 2060: Hydrogen as Energy Carrier in Malaysian Primary Energy Mix – Developing P2G Case
Mar 2021
Publication
The transition of Malaysia from fossil fuels to renewable energy sources provides significant challenges and opportunities for various energy sectors. Incorporation of H2 in the primary energy mix requires a deal of complexity in its relation to production transportation and end-use. The Sarawak State Government in Malaysia implemented a hydrogen energy roadmap for the year 2005–2030 on the state-level but despite the great enthusiasm and full support given by the government the development of hydrogen technology is still far from its goals. This is due to several factors that hinder its progress including (1) inability of hydrogen to be integrated with current primary energy infrastructure (2) limited technology resources to produce sustainable hydrogen and (3) lack of technical expertise in the field of hydrogen. In this paper a potential national roadmap and milestones are presented based on the power-to-gas (P2G) approach combined with its implications on the national natural gas (NG) pipeline network. Besides that the long-term and short-term strategies and implementation mechanisms are discussed in detail. Furthermore complete research schemes are formulated to be inline with the presented vision to further enhance technology development and implementation.
Combustion Characteristics of Hydrogen Direct Injection in a Helium–oxygen Compression Ignition Engine
Jul 2022
Publication
The ignition of hydrogen in compression ignition (CI) engines by adding noble gas as a working gas can yield excellent thermal efficiency due to its high specific heat ratio. This paper emphasizes the potential of helium–oxygen atmosphere for hydrogen combustion in CI engines and provides data on the engine configuration. A simulation was conducted using Converge CFD software based on the Yanmar NF19SK engine parameters. Helium–oxygen atmosphere compression show promising hydrogen autoignition results with the in-cylinder temperature was significantly higher than that of air during the compression stroke. In a compression ignition engine with a low compression ratio (CR) and intake temperature helium–oxygen atmosphere is recognized as the best working gas for hydrogen combustion. The ambient intake temperature was sufficient for hydrogen ignition in low CR with minimal heat flux effect. The best intake temperature for optimum engine efficiency in a low CR engine is 340 K and the engine compression ratio for optimum engine efficiency at ambient intake temperature is CR12 with an acceptable cylinder wall heat flux value. The helium–oxygen atmosphere as a working gas for hydrogen combustion in CI engines should be consider based on the parameter provided for clean energy transition with higher thermal efficiency.
Study of Heat Loss Mechanism in Argon-circulated Hydrogen Engine Combustion Chamber Wall Surface Conditions
Jul 2022
Publication
Hydrogen fuel in internal combustion engine gives a very big advantage to the transportation sector especially in solving the greenhouse emission problem. However there are only few research discovered the ability of argon as a working gas in hydrogen combustion in internal combustion engine. The high temperature rises from the argon compression tend to result in heat loss problem. This research aims to study the heat loss mechanism on wall surface condition in the combustion chamber. Experiments were conducted to study the effects of different heat flux sensor locations and the effect of ignition delay on heat flux. Local heat flux measurement was collected and images were observed using high speed shadowgraph images. The ignition delay that occurred near the combustion wall will result in larger heat loss throughout the combustion process. Higher ambient pressure results in a bigger amount of heat flux value. Other fundamental characteristics were obtained and discussed which may help in contributing the local heat loss data of an argon-circulated hydrogen engine in future engine operation.
Parametric Study and Electrocatalyst of Polymer Electrolyte Membrane (PEM) Electrolysis Performance
Jan 2023
Publication
An investigation was conducted to determine the effects of operating parameters for various electrode types on hydrogen gas production through electrolysis as well as to evaluate the efficiency of the polymer electrolyte membrane (PEM) electrolyzer. Deionized (DI) water was fed to a single-cell PEM electrolyzer with an active area of 36 cm2 . Parameters such as power supply (50–500 mA/cm2 ) feed water flow rate (0.5–5 mL/min) water temperature (25−80 ◦C) and type of anode electrocatalyst (0.5 mg/cm2 PtC [60%] 1.5 mg/cm2 IrRuOx with 1.5 mg/cm2 PtB 3.0 mg/cm2 IrRuOx and 3.0 mg/cm2 PtB) were varied. The effects of these parameter changes were then analyzed in terms of the polarization curve hydrogen flowrate power consumption voltaic efficiency and energy efficiency. The best electrolysis performance was observed at a DI water feed flowrate of 2 mL/min and a cell temperature of 70 ◦C using a membrane electrode assembly that has a 3.0 mg/cm2 IrRuOx catalyst at the anode side. This improved performance of the PEM electrolyzer is due to the reduction in activation as well as ohmic losses. Furthermore the energy consumption was optimal when the current density was about 200 mA/cm2 with voltaic and energy efficiencies of 85% and 67.5% respectively. This result indicates low electrical energy consumption which can lower the operating cost and increase the performance of PEM electrolyzers. Therefore the optimal operating parameters are crucial to ensure the ideal performance and durability of the PEM electrolyzer as well as lower its operating costs.
Wettability of Shale–brine–H2 System and H2-brine Interfacial Tension for Assessment of the Sealing Capacities of Shale Formations During Underground Hydrogen Storage
Jul 2022
Publication
Replacement of fossil fuels with clean hydrogen has been recognized as the most feasible approach of implementing CO2-free hydrogen economy globally. However large-scale storage of hydrogen is a critical component of hydrogen economy value chain because hydrogen is the lightest molecule and has moderately low volumetric energy content. To achieve successful storage of buoyant hydrogen at the subsurface and convenient withdrawal during the period of critical energy demand the integrity of the underground storage rock and overlying seal (caprock) must be assured. Presently there is paucity of information on hydrogen wettability of shale and the interfacial properties of H2/brine system. In this research contact angles of shale/H2/brine system and hydrogen/brine interfacial tension (IFT) were measured using Krüss drop shape analyzer (DSA 100) at 50 ◦C and varying pressure (14.7–1000 psi). A modified form of sessile drop approach was used for the contact angles measurement whereas the H2- brine IFT was measured through the pendant drop method. H2-brine IFT values decreased slightly with increasing pressure ranging between 63.68◦ at 14.7 psia and 51.29◦ at 1000 psia. The Eagle-ford shale with moderate total organic carbon (TOC) of 3.83% attained fully hydrogen-wet (contact angle of 99.9◦ ) and intermediate-wet condition (contact angle of 89.7◦ ) at 14.7 psi and 200 psi respectively. Likewise the Wolf-camp shale with low TOC (0.30%) attained weakly water-wet conditions with contact angles of 58.8◦ and 62.9◦ at 14.7 psi and 200 psi respectively. The maximum height of hydrogen that can be securely trapped by the Wolf-camp shale was approximately 325 meters whereas the value was merely 100 meters for the Eagle-ford shale. Results of this study will aid in assessment of hydrogen storage capacity of organic-rich shale (adsorption trapping) as well as evaluation of the sealing potentials of low TOC shale (caprock) during underground hydrogen storage.
Decarbonizing the Future for the Transportation and Aviation Industries: Green Hydrogen as the Sustainable Fuel Solution
Jun 2025
Publication
The pressure to move to sustainable energy sources is obvious in today's fast changing energy environment. In this context green hydrogen appears as a beacon of hope with the potential to reinvent the paradigms of energy consumption particularly in the transportation and aviation sectors. Hydrogen has long been intriguing owing to its unique characteristics. It is not only an energy transporter; it has the power to alter the game. Its growing significance is due to its capacity to decarbonize energy generation. Traditional hydrogen generation techniques have contributed considerably to world CO2 emissions accounting for over 2% of total emissions. This environmental problem is successfully addressed by the development of green hydrogen which is created from renewable energy sources. The International Energy Agency (IEA) predicts a 25 to 30 percent increase in global energy consumption by 2040 which is a very grim scenario. If continue to rely on coal and oil this growing demand will result in greater CO2 emissions exacerbating climate change's consequences. In this situation green hydrogen is not only an option but a need. Because green hydrogen has properties with conventional fuels it can be simply integrated into current infrastructure. This harmonic integration ensures that the shift to hydrogen-based solutions in these sectors would not demand a complete redesign of the present systems assuring cost-effectiveness and practicality. However like with any energy source green hydrogen has obstacles. Its combustibility and probable explosiveness have been cited as causes for concern. However developments in safety measures have successfully mitigated these dangers ensuring that hydrogen may be used safely and efficiently across various applications. A further difficulty is its energy density particularly in comparison to conventional fuels. While its energy-to-weight ratio may be good its bulk poses challenges particularly in the aviation industry where space is at a premium. Beyond its direct use as a fuel green hydrogen has potential in auxiliary capacities. It may be used as a dependable backup energy source during power outages as well as in a variety of different sectors and uses ranging from manufacturing to residential. Green hydrogen's adaptability demonstrates its potential to infiltrate all sectors of our economy. Storage is an important enabler for broad hydrogen use. Effective hydrogen storage technologies guarantee not only its availability but also its viability as a source of energy. Current research and advancements in this field are encouraging which strengthens the argument for green hydrogen. At conclusion green hydrogen is in the vanguard of sustainable energy solutions particularly for the transportation and aviation industries. In our collaborative quest of a sustainable future its unique features and environmental advantages make it a vital asset. As we explore further into the complexities of green hydrogen in this publication we want to shed light on its potential obstacles and future route.
Sustainable E-Fuels: Green Hydrogen, Methanol and Ammonia for Carbon-Neutral Transportation
Dec 2023
Publication
Increasingly stringent sustainability and decarbonization objectives drive investments in adopting environmentally friendly low and zero-carbon fuels. This study presents a comparative framework of green hydrogen green ammonia and green methanol production and application in a clear context. By harnessing publicly available data sources including from the literature this research delves into the evaluation of green fuels. Building on these insights this study outlines the production process application and strategic pathways to transition into a greener economy by 2050. This envisioned transformation unfolds in three progressive steps: the utilization of green hydrogen green ammonia and green methanol as a sustainable fuel source for transport applications; the integration of these green fuels in industries; and the establishment of mechanisms for achieving the net zero. However this research also reveals the formidable challenges of producing green hydrogen green ammonia and green methanol. These challenges encompass technological intricacies economic barriers societal considerations and far-reaching policy implications necessitating collaborative efforts and innovative solutions to successfully develop and deploy green hydrogen green ammonia and green methanol. The findings unequivocally demonstrate that renewable energy sources play a pivotal role in enabling the production of these green fuels positioning the global transition in the landscape of sustainable energy.
A Review on the Environmental Performance of Various Hydrogen Production Technologies: An Approach Towards Hydrogen Economy
Nov 2023
Publication
Demand for hydrogen has grown and continues to rise as a versatile energy carrier. Hydrogen can be produced from renewable and non-renewable energy sources. A wide range of technologies to produce hydrogen in an environmentally friendly way have been developed. As the life cycle assessment (LCA) approach has become popular recently including in the hydrogen energy system this paper comprehensively reviews the LCA of hydrogen production technology. A subdivision based on the trends in the LCA studies hydrogen production technology goal and scope definition system boundary and environmental performance of hydrogen production is discussed in this review. Thermochemical hydrogen production is the most studied technology in LCA. However utilizing natural resources especially wind power in the electrolysis process stands out as an environmentally preferable solution when compared to alternative production processes. It is crucial to rethink reactors and other production-related equipment to improve environmental performance and increase hydrogen production efficiency. Since most of the previous LCA studies were conducted in developed countries and only a few were from developing countries a way forward for LCA application on hydrogen in developing countries was also highlighted and discussed. This review provides a comprehensive insight for further research on hydrogen production technology from an LCA perspective.
Process Integration of Hydrogen Production Using Steam Gasification and Water-Gas Shift Reactions: A Case of Response Surface Method and Machine Learning Techniques
May 2024
Publication
An equilibrium-based steady-state simulator model that predicts and optimizes hydrogen production from steam gasification ofbiomass is developed using ASPEN Plus software and artificial intelligence techniques. Corn cob’s chemical composition wascharacterized to ensure the biomass used as a gasifier and with potential for production of hydrogen. Artificial intelligence is usedto examine the effects of the significant input variables on response variables such as hydrogen mole fraction and hydrogen energycontent. Optimizing the steam-gasification process using response surface methodology (RSM) considering a variety of biomass-steam ratios was carried out to achieve the best results. Hydrogen yield and the impact of main operating parameters wereconsidered. A maximum hydrogen concentration is found in the gasifier and water-gas shift (WGS) reactor at the highest steam-to-biomass (S/B) ratio and the lowest WGS reaction temperature while the gasification temperature has an optimum value. ANFISwas used to predict hydrogen of mole fraction 0.5045 with the input parameters of S/B ratio of 2.449 and reactor pressure andtemperature of 1 bar and 848°C respectively. With the steam-gasification model operating at temperature (850°C) pressure (1 bar)and S/B ratio of 2.0 an ASPEN simulator achieved a maximum of 0.5862 mole fraction of hydrogen while RSM gave an increaseof 19.0% optimum hydrogen produced over the ANFIS prediction with the input parameters of S/B ratio of 1.053 and reactorpressure and temperature of 1 bar and 850°C respectively. Varying the gasifier temperature and S/B ratio have on the other handa crucial effect on the gasification process with artificial intelligence as a unique tool for process evaluation prediction andoptimization to increase a significant impact on the products especially hydrogen.
Industrial and Academic Collaboration Strategies on Hydrogen Fuel Cell Technology Development in Malaysia
Nov 2013
Publication
Hydrogen fuel cells are electrochemical power generators of high conversion efficiency and incredibly clean operation. Throughout the world the growth of fuel cell research and application has been very rapid in the last ten years where successful pilot projects on many areas have been implemented. In Malaysia approximately RM40 million has been granted to academic research institutions for fuel cell study and development. Recently Malaysia saw the emergence of its first hydrogen fuel cell developer signaling the readiness of the industrial sector to be involved in marketing the potential of fuel cells. Focusing mainly on Polymer Electrolyte Membrane fuel cell technology this paper demonstrates the efforts by Malaysian institutions both industrial and academic to promote hydrogen fuel cell education training application R&D as well as technology transfer. Emphasis is given to the existing collaboration between G-Energy Technologies and UniversitiTeknologi MARA that culminates with the successful application of a locally developed fuel cell system for a single-seated vehicle. Briefs on the potential of realizing a large-scale utilization of this clean technology into Malaysia’s mainstream power industry domestic consumers and energy consuming industries is also discussed. Key challenges are also identified where pilot projects government policy and infrastructural development is central to strengthen the prospect of hydrogen fuel cell implementation in Malaysia.
Elevating the Prospects of Green Hydrogen (H2) Production Through Solar-powered Water Splitting Devices: A Systematic Review
May 2024
Publication
As the commercialisation of two contrasting solar-powered water splitting devices with lower TRLs of proton exchange membrane (PEM) electrolyser systems and photoelectrochemical (PEC) systems gains momentum the path towards a sustainable H2 economy is taking shape. Ongoing pilot projects and demonstration plants are proving the feasibility and potential of these technologies in real-world applications. However to ensure their success we must confront the critical challenges of cost reduction and efficiency enhancement making green H2 economically competitive with traditional production methods. To achieve this a collaborative effort among academia industry and policymakers is paramount. This comprehensive review begins by examining traditional water electrolysis methods focusing on the production of green H2 through electrochemical splitting. It delves into crucial components and advancements in the PEM systems addressing challenges related to catalysts membranes gas diffusion layers and bipolar plates. The review also explores solar-driven PEC water splitting emphasizing the significance of efficient photoelectrodes and reactor design. Additionally it discusses the integration of photovoltaic cells with electrochemical or PEC systems for higher H2 yield. Commercialisation is underway and this endeavour necessitates a collaborative approach with active involvement from academia industry and policymakers. This collective effort not only propels us towards greener and more sustainable energy solutions but also represents a transformative step in the global journey towards a sustainable and environmentally conscious economy.
Investigation of Performance of Anion Exchange Membrane (AEM) Electrolysis with Different Operating Conditions
Mar 2023
Publication
In this work the performance of anion exchange membrane (AEM) electrolysis is evaluated. A parametric study is conducted focusing on the effects of various operating parameters on the AEM efficiency. The following parameters—potassium hydroxide (KOH electrolyte concentration (0.5–2.0 M) electrolyte flow rate (1–9 mL/min) and operating temperature (30–60 ◦C)—were varied to understand their relationship to AEM performance. The performance of the electrolysis unit is measured by its hydrogen production and energy efficiency using the AEM electrolysis unit. Based on the findings the operating parameters greatly influence the performance of AEM electrolysis. The highest hydrogen production was achieved with the operational parameters of 2.0 M electrolyte concentration 60 ◦C operating temperature and 9 mL/min electrolyte flow at 2.38 V applied voltage. Hydrogen production of 61.13 mL/min was achieved with an energy consumption of 48.25 kW·h/kg and an energy efficiency of 69.64%.
Utilization of Hydrogen in Gas Turbines: A Comprehensive Review
Feb 2022
Publication
The concerns regarding the consumption of traditional fuels such as oil and coal have driven the proposals for several cleaner alternatives in recent years. Hydrogen energy is one of the most attractive alternatives for the currently used fossil fuels with several superiorities such as zero-emission and high energy content. Hydrogen has numerous advantages compared to conventional fuels and as such has been employed in gas turbines (GTs) in recent years. The main benefit of using hydrogen in power generation with the GT is the considerably lower emission of greenhouse gases. The performance of the GTs using hydrogen as a fuel is influenced by several factors including the performance of the components the operating condition ambient condition etc. These factors have been investigated by several scholars and scientists in this field. In this article studies on hydrogen-fired GTs are reviewed and their results are discussed. Furthermore some recommendations are proposed for the upcoming works in this field.
Recent Developments in Methane Decomposition over Heterogenous Catalysts: An Overview
Apr 2020
Publication
The production of hydrogen to be used as an alternative renewable energy has been widely explored. Among various methods for producing hydrogen from hydrocarbons methane decomposition is suitable for generating hydrogen with zero greenhouse gas emissions. The use of high temperatures as a result of strong carbon and hydrogen (C–H) bonds may be reduced by utilizing a suitable catalyst with appropriate catalyst support. Catalysts based on transition metals are preferable in terms of their activeness handling and low cost in comparison with noble metals. Further development of catalysts in methane decomposition has been investigated. In this review the recent progress on methane decomposition in terms of catalytic materials preparation method the physicochemical properties of the catalysts and their performance in methane decomposition were presented. The formation of carbon as part of the reaction was also discussed.
Combustion Characteristics of Hydrogen in a Noble Gas Compression Ignition Engine
Jul 2021
Publication
Hydrogen eliminates carbon emissions from compression ignition (CI) engines while noble gases eliminate nitrogen oxide (NOx) emissions by replacing nitrogen. Noble gases can increase the in-cylinder temperature during the compression stroke due to their high specific heat ratio. This paper aims to find the optimum parameters for hydrogen combustion in an argon–oxygen atmosphere and to study hydrogen combustion in all noble gases providing hydrogen combustion data with suitable engine parameters to predict hydrogen ignitability under different conditions. Simulations are performed with Converge CFD software based on the Yanmar NF19SK direct injection CI (DICI) engine parameters. The results are validated with the experimental results of hydrogen combustion in an argon–oxygen atmosphere with a rapid compression expansion machine (RCEM) and modifications of the hydrogen injection timing and initial temperature are proposed. Hydrogen ignition in an argon atmosphere is dependent on a minimum initial temperature of 340 K but the combustion is slightly unstable. Helium and neon are found to be suitable for hydrogen combustion in low compression ratio (CR) engines. However krypton and xenon require temperature modification and a high CR for stable ignition. Detailed parameter recommendations are needed to improve hydrogen ignitability in conventional diesel engines with the least engine modification.
Nanomaterials: Paving the Way for the Hydrogen Energy Frontier
Jan 2024
Publication
This comprehensive review explores the transformative role of nanomaterials in advancing the frontier of hydrogen energy specifcally in the realms of storage production and transport. Focusing on key nanomaterials like metallic nanoparticles metal–organic frameworks carbon nanotubes and graphene the article delves into their unique properties. It scrutinizes the application of nanomaterials in hydrogen storage elucidating both challenges and advantages. The review meticulously evaluates diverse strategies employed to overcome limitations in traditional storage methods and highlights recent breakthroughs in nanomaterial-centric hydrogen storage. Additionally the article investigates the utilization of nanomaterials to enhance hydrogen production emphasizing their role as efcient nanocatalysts in boosting hydrogen fuel cell efciency. It provides a comprehensive overview of various nanocatalysts and their potential applications in fuel cells. The exploration extends to the realm of hydrogen transport and delivery specifcally in storage tanks and pipelines ofering insights into the nanomaterials investigated for this purpose and recent advancements in the feld. In conclusion the review underscores the immense potential of nanomaterials in propelling the hydrogen energy frontier. It emphasizes the imperative for continued research aimed at optimizing the properties and performance of existing nanomaterials while advocating for the development of novel nanomaterials with superior attributes for hydrogen storage production and transport. This article serves as a roadmap shedding light on the pivotal role nanomaterials can play in advancing the development of clean and sustainable hydrogen energy technologies.
Hydrogen Fuel Cell Legal Framework in the United States, Germany, and South Korea—A Model for a Regulation in Malaysia
Feb 2021
Publication
As a party to the United Nation Framework Convention on Climate Change (UNFCCC) Malaysia is committed to reduce its greenhouse gases (GHG) emission intensity of gross domestic product (GDP) by 45% by 2030 relative to the emission intensity of GDP in 2005. One of the ways for Malaysia to reduce its GHG emission is to diversify its energy mix and to include hydrogen fuel cell (HFC) in its energy mix. Since Malaysia does not have any legal framework for HFCs it is best to see how other countries are doing and how can it be replicated in Malaysia. This paper reviews the HFC legal framework in the United States Germany and South Korea as these countries are among those that have advanced themselves in this technology. The researchers conducted a library-based research and obtained the related materials from online databases and public domain. Based on the reviews the researchers find that these countries have a proper legal framework in place for HFC. With these legal frameworks funds will be available to support research and development as well as demonstration of HFC. Thus it is recommended that Malaysia to have a proper HFC legal framework in place in order to support the development of the HFC industry.
Materials on the Frontier: A Review on Groundbreaking Solutions for Hydrogen Storage Applications
Mar 2025
Publication
As global energy shifts toward sustainable solutions switching to sustainable energy particularly those involving energy storage from hydrogen relies on effective storage technologies. This is necessary for harnessing the potential of hydrogen as a clean energy carrier. This review discussed the latest advancements in materials designed to improve hydrogen storage efficiency safety and scalability. The articles reported different storage materials such as metal hydrides chemical hydrides advanced adsorbents and their challenges and prospects. Developing innovations like nanostructured and hybrid materials are explained showing how these cutting-edge approaches improve hydrogen kinetics. However despite the advancements challenges like feasibility and sustainability remain. Hence this study discusses these barriers through life cycle assessments and recycling. Moreover the study offers an understanding of the applications of these materials illustrating their prospects to simplify a hydrogen economy. Through examining current research and identifying important trends the article aims to illuminate the way forward for materials science in hydrogen storage applications. The findings highlight the importance of material development and emphasise the collaborative efforts researchers require to realise the potential of hydrogen as a keystone of sustainable energy systems.
A Review of Life Cycle Assessment for Fuel Cell Technologies: Advancing Clean Energy and Climate Solutions
Jun 2025
Publication
Fuel cell (FC) technologies are often regarded as a sustainable alternative to conventional combustion-based energy systems due to their low environmental impact and high efficiency. Thorough environmental assessments using Life Cycle Assessment (LCA) methodologies are needed to understand and mitigate their impacts. However there has been a lack of comprehensive reviews on LCA studies across all major types of FCs. This study reviews and synthesizes results from 44 peer-reviewed LCA studies from 2015 to 2024 covering six major FC types: alkaline (AFC) direct methanol (DMFC) molten carbonate (MCFC) proton- exchange membrane (PEMFC) solid oxide (SOFC) and phosphoric acid (PAFC). The review provides an updated overview of LCA practices and results over the past decade while identifying methodological inconsistencies and gaps. PEMFCs are the most frequently assessed FC typology covering 49 % of the studies followed by SOFCs at 38 % with no studies on DMFCs. Only 11 % of comparative studies carry out inter-comparison between FC types. Discrepancies in system boundary definitions across studies are identified highlighting the need for standardization to enhance comparability between studies. Global Warming Potential (GWP) evaluated in 100 % of the studies is the most assessed impact category. Fuel supply in the use phase a major contributor to greenhouse gas (GHG) emissions is under-assessed as it is usually aggregated with Operation and Maintenance (O&M) phase instead of discussed separately. GWP of energy production by all FC typologies spans from 0.026 to 1.76 kg CO₂-equivalent per kWh. Insufficient quantitative data for a meta-analysis and limited inter-comparability across FC types are noted as critical gaps. The study highlights the need for future research and policies focusing on green hydrogen supply and circular economy practices to improve FC sustainability.
Hydrogen Permeation Resistance of PVDF–Graphene Nanocomposite Coatings for Metallic Pipelines
Aug 2025
Publication
Hydrogen-induced steel embrittlement imposes a technical difficulty in facilitating effective and safe hydrogen transportation via pipelines. This investigative study assesses the potency of polyvinylidene fluoride (PVDF)–graphene-based composite coatings in the inhibition of hydrogen permeation. Spin coating was the method selected for this study and varying graphene concentrations ranging from 0.1 to 1wt% were selected and applied to 306 stainless steel substrates. A membrane permeation cell was used in the evaluation of hydrogen permeability while the impact of graphene loading on coating performance was analyzed using the response surface methodology (RSM). The outcomes showed an inversely proportional relationship between the graphene concentration and hydrogen ingress. The permeation coefficient for pure PVDF was recorded as 16.74 which decreased to 14.23 12.10 and 11.46 for 0.3 0.5 and 1.0 wt% PVDF-G respectively with the maximum reduction of 31.6% observed at 1.0 wt%. ANOVA established statistical significance along with indications of strong projection dependability. However the inhibition reduction stabilized with increasing graphene concentrations likely caused by nanoparticle agglomeration. The results support the notion of PVDF–graphene’s potential as a suitable coating for the transformation of pipelines for hydrogen transport infrastructure. This research will aid in the establishment of suitable contemporary barrier coating materials which will enable the safe utilization of hydrogen energy in the current energy transportation grid.
Efficiency Measurement and Trend Analysis of the Hydrogen Energy Industry Chain in China
Apr 2025
Publication
Hydrogen energy characterized by its abundant resources green and lowcarbon attributes and wide-ranging applications is a critical energy source for achieving carbon peaking and carbon neutrality goals. The operational efficiency of the hydrogen energy industrial chain is pivotal in determining the security of its supply chain and its contribution to China’s energy transition. This study investigates the efficiency of China’s hydrogen energy industrial chain by selecting 30 listed companies primarily engaged in hydrogen energy as the research sample. A three-stage data envelopment analysis (DEA) model is applied to assess the industry’s comprehensive technical efficiency pure technical efficiency and scale efficiency. Additionally kernel density estimation is utilized to analyze efficiency trends over time. Key factors influencing efficiency are identified and targeted recommendations are provided to enhance the performance and sustainability of the hydrogen energy industrial chain. These findings offer valuable insights to support the development and resilience of China’s hydrogen energy industry
Advancement in Hydrogen Production, Application and Strategy Towards Sustainable Energy: Malaysian Case Study
Aug 2025
Publication
Biohydrogen is known for its clean fuel properties with zero emissions. It serves as a reliable alternative to fossil fuel. This paper analyses the status of bio-hydrogen production in Malaysia and the on-going efforts on its advancement. Critical discussions were put forward on biohydrogen production from thermochemical and biological technologies governing associated technological issues and development. Moreover a comprehensive and vital overview has been made on Malaysian and global polices with road maps for the development of biohydrogen and its application in different sectors. This review article provides a framework for researchers on bio-hydrogen production technologies investors and the government to align policies for the biohydrogen based economy. Current biohydrogen energy outlook for production installation units and storage capacity are the key points to be highlighted from global and Malaysia’s perspectives. This critical and comprehensive review provides a strategic route for the researcher to research towards sustainable technology. Current policies related to hydrogen as fuel infrastructure in Malaysia and commercialization are highlighted. Malaysia is also gearing towards clean and decarbonization planning.
Advancing Hydrogen Storage: Explainable Machine Learning Models for Predicting Hydrogen Uptake in Metal-organic Frameworks
Sep 2025
Publication
Metal organic frameworks (MOFs) exhibit exceptional efficacy in hydrogen storage owing to their distinctive characteristics including elevated gravimetric densities rapid kinetics and reversibility. An in-depth look at existing literature indicates that while there are many studies using machine learning (ML) algorithms to develop predictive models for estimating hydrogen uptake by MOFs a great number of these models are not explainable. The novelty of this work lies in the integration of explainability approaches and ML models providing both accuracy and interpretability which is rarely addressed in existing studies. To fill this gap this paper attempts to develop explainable ML models for forecasting the hydrogen storage capacity of MOFs using three ML techniques including Bayesian regularized neural networks (BRANN) least squares support vector machines (LSSVM) and the extra tree algorithm (ET). An MOF databank comprising 1729 data points was assembled from literature. Surface area temperature pore volume and pressure were employed as input variables in this database. The findings demonstrate that of the three algorithms the ET intelligent model attained exceptional performance yielding precise estimates with a root mean square error (RMSE) of 0.1445 mean absolute error (MAE) of 0.0762 and a correlation coefficient (R2 ) of 0.995. In addition a novel contribution of this study is the generation of an explicit formula derived from BRANN enabling straightforward implementation of hydrogen storage predictions without requiring retraining of complex models. The sensitivity analysis employing Shapley Additive Explanation technique revealed that pressure and surface area were the most significant features influencing hydrogen storage with relevance values of 0.84 and 0.59 respectively. Furthermore the outlier detection evaluation using the leverage method showed that approximately 98 % of the utilized MOFs data are trustworthy and fell within the acceptable range. Altogether this work establishes a distinctive framework that combines accuracy interpretability and practical usability advancing the state of predictive modelling for hydrogen storage in MOFs.
An Overview of Hydrogen Storage Technologies - Key Challenges and Opportunities
Jul 2024
Publication
Hydrogen energy has been proposed as a reliable and sustainable source of energy which could play an integral part in demand for foreseeable environmentally friendly energy. Biomass fossil fuels waste products and clean energy sources like solar and wind power can all be employed for producing hydrogen. This comprehensive review paper provides a thorough overview of various hydrogen storage technologies available today along with the benefits and drawbacks of each technology in context with storage capacity efficiency safety and cost. Since safety concerns are among the major barriers to the broad application of H2 as a fuel source special attention has been paid to the safety implications of various H2 storage techniques. In addition this paper highlights the key challenges and opportunities facing the development and commercialization of hydrogen storage technologies including the need for improved materials enhanced system integration increased awareness and acceptance. Finally recommendations for future research and development with a particular focus on advancing these technologies towards commercial viability.
Techno-economic Analysis and Dynamic Operation of Green Hydrogen-integrated Microgrid: An Application Study
Aug 2025
Publication
The shift to renewable energy sources requires systems that are not only environmentally sustainable but also cost-effective and reliable. Mitigating the inherent intermittency of renewable energy optimally managing the hybrid energy storage efficiently integrating the microgrid with the power grid and maximizing the lifespan of system components are the significant challenges that need to be addressed. With this aim the paper proposes an economic viability assessment framework with an optimized dynamic operation approach to determine the most stable cost-effective and environmentally sound system for a specific location and demand. The green integrated hybrid microgrid combines photovoltaic (PV) generation battery storage an electrolyzer a hydrogen tank and a fuel cell tailored for deployment in remote areas with limited access to conventional infrastructure. The study’s control strategy focuses on managing energy flows between the renewable energy resources battery and hydrogen storage systems to maximize autonomy considering real-time changes in weather conditions load variations and the state of charge of both the battery and hydrogen storage units. The core system’s components include the interlinking converter which transfers power between AC and DC grids and the decentralized droop control approach which adjusts the converter’s output to ensure balanced and efficient power sharing particularly during overload conditions. A cloud-based Internet of Things (IoT) platform has been employed allowing continuous monitoring and data analysis of the green integrated microgrid to provide insights into the system's health and performance during the dynamic operation. The results presented in this paper confirmed that the proposed framework enabled the strategic use of energy storage particularly hydrogen systems. The optimal operational control of green hydrogen-integrated microgrid can indeed mitigate voltage and frequency fluctuations caused by variable solar input ensuring stable power delivery without reliance on the main grid or fossil fuel backups.
Technology Roadmap for Hydrogen-fuelled Transportation in the UK
Apr 2023
Publication
Transportation is the sector responsible for the largest greenhouse gas emission in the UK. To mitigate its impact on the environment and move towards net-zero emissions by 2050 hydrogen-fuelled transportation has been explored through research and development as well as trials. This article presents an overview of relevant technologies and issues that challenge the supply use and marketability of hydrogen for transportation application in the UK covering on-road aviation maritime and rail transportation modes. The current development statutes of the different transportation modes were reviewed and compared highlighting similarities and differences in fuel cells internal combustion engines storage technologies supply chains and refuelling characteristics. In addition common and specific future research needs in the short to long term for the different transportation modes were suggested. The findings showed the potential of using hydrogen in all transportation modes although each sector faces different challenges and requires future improvements in performance and cost development of innovative designs refuelling stations standards and codes regulations and policies to support the advancement of the use of hydrogen.
Towards Enhanced Durability: A Review of Fuel Cell Electric Vehicle Development
Aug 2025
Publication
Fuel cell electric vehicles (FCEVs) provide a viable answer to transportation issues caused by fossil fuel limitations and environmental concerns. This review presents a thorough evaluation of the most recent advances in FCEV durability research. It addresses 4 major topics: component upgrades technical control techniques test optimization and durability prediction. Upgrades to components include improved catalysts bipolar plates gas diffusion layers proton exchange membranes and plant balancing. Technical control solutions include power energy temperature ventilation and control management. Stress acceleration and cold start tests are examples of test optimization whereas durability prediction requires parameter selection real-time monitoring dynamic modeling and lifespan prediction. This review also makes some novel recommendations targeted at improving the endurance of FCEVs. These include measures for raising public awareness lowering prices while increasing performance improving subsystems for greater durability updating health diagnostics to prevent performance deterioration and implementing supporting regulations to encourage industry upgrading. These findings are expected to accelerate the adoption of FCEVs and the transition to a more sustainable transportation system.
Photovoltaic-Assisted Photo(electro)catalytic Hydrogen Production: A Review
Aug 2023
Publication
The idea of supporting the Sustainable Development Goals (SDGs) has inspired researchers around the world to explore more environmentally friendly energy generation and production methods especially those related to solar and hydrogen energy. Among the various available sustainable energy technologies photo(electro)catalytic hydrogen production has been competitively explored benefiting from its versatile platform to utilize solar energy for green hydrogen production. Nevertheless the bottleneck of this photo(electro)catalytic system lies within its high voltage required for water electrolysis (>1.23 V) which affects the economic prospects of this sustainable technology. In this regard coupling the photo(electro)catalytic system with a solar-powered photovoltaic (PV) system (PV-PEC) to unleash the fascinating properties and readiness of this system has heightened attention among the scientific community. In this context this review begins by elucidating the basic principles of PV-PEC systems followed by an exploration of various types of solar PV technology and the different types of semiconductors used as photocatalysts in the PEC system. Subsequently the main challenges faced by the PV-PEC system are presented covering areas such as efficiency stability and cost-effectiveness. Finally this review delves into recent research related to PV-PEC systems discussing the advancements and breakthroughs in this promising technology. Furthermore this review provides a forecast for the future prospects of the PV-PEC system highlighting the potential for its continued development and widespread implementation as a key player in sustainable hydrogen production.
Sustainable Vehicles for Decarbonizing the Transport Sector: A Comparison of Biofuel, Electric, Fuel Cell and Solar-powered Vehicles
Mar 2024
Publication
Climate change necessitates urgent action to decarbonize the transport sector. Sustainable vehicles represent crucial alternatives to traditional combustion engines. This study comprehensively compares four prominent sustainable vehicle technologies: biofuel-powered vehicles (BPVs) fuel cell vehicles (FCVs) electric vehicles (EVs) and solar vehicles. We examine each technology’s history development classification key components and operational principles. Furthermore we assess their sustainability through technical factors environmental impacts cost considerations and policy dimensions. Moreover the discussion section addresses the challenges and opportunities associated with each technology and assesses their social impact including public perception and adoption. Each technology offers promise for sustainable transportation but faces unique challenges. Policymakers industry stakeholders and researchers must collaborate to address these challenges and accelerate the transition toward a decarbonized transport future. Potential future research areas are identified to guide advancements in sustainable vehicle technologies.
Empowering Fuel Cell Electric Vehicles Towards Sustainable Transportation: An Analytical Assessment, Emerging Energy Management, Key Issues, and Future Research Opportunities
Oct 2024
Publication
Fuel cell electric vehicles (FCEVs) have received significant attention in recent times due to various advantageous features such as high energy efficiency zero emissions and extended driving range. However FCEVs have some drawbacks including high production costs; limited hydrogen refueling infrastructure; and the complexity of converters controllers and method execution. To address these challenges smart energy management involving appropriate converters controllers intelligent algorithms and optimizations is essential for enhancing the effectiveness of FCEVs towards sustainable transportation. Therefore this paper presents emerging energy management strategies for FCEVs to improve energy efficiency system reliability and overall performance. In this context a comprehensive analytical assessment is conducted to examine several factors including research trends types of publications citation analysis keyword occurrences collaborations influential authors and the countries conducting research in this area. Moreover emerging energy management schemes are investigated with a focus on intelligent algorithms optimization techniques and control strategies highlighting contributions key findings issues and research gaps. Furthermore the state-of-the-art research domains of FCEVs are thoroughly discussed in order to explore various research domains relevant outcomes and existing challenges. Additionally this paper addresses open issues and challenges and offers valuable future research opportunities for advancing FCEVs emphasizing the importance of suitable algorithms controllers and optimization techniques to enhance their performance. The outcomes and key findings of this review will be helpful for researchers and automotive engineers in developing advanced methods control schemes and optimization strategies for FCEVs towards greener transportation.
Assessment of Wettability and Rock-fluid Interfacial Tension of Caprock: Implications for Hydrogen and Carbon Dioxide Geo-storage
Mar 2022
Publication
Underground hydrogen (H2) storage (UHS) and carbon dioxide (CO2) geo-storage (CGS) are prominent methods of meeting global energy needs and enabling a low-carbon global economy. The pore-scale distribution reservoir-scale storage capacity and containment security of H2 and CO2 are significantly influenced by interfacial properties including the equilibrium contact angle (θE) and solid-liquid and solid-gas interfacial tensions (γSL and γSG). However due to the technical constraints of experimentally determining these parameters they are often calculated based on advancing and receding contact angle values. There is a scarcity of θE γSL and γSG data particularly related to the hydrogen structural sealing potential of caprock which is unavailable in the literature. Young's equation and Neumann's equation of state were combined in this study to theoretically compute these three parameters (θE γSL and γSG) at reservoir conditions for the H2 and CO2 geo-storage potential. Pure mica organic-aged mica and alumina nano-aged mica substrates were investigated to explore the conditions for rock wetting phenomena and the sealing potential of caprock. The results reveal that θE increases while γSG decreases with increasing pressure organic acid concentration and alkyl chain length. However γSG decreases with increasing temperatures for H2 gas and vice versa for CO2. In addition θE and γSL decrease whereas γSG increases with increasing alumina nanofluid concentration from 0.05 to 0.25 wt%. Conversely θE and γSL increase whereas γSG decreases with increasing alumina nanofluid concentration from 0.25 to 0.75 wt%. The hydrogen wettability of mica (a proxy of caprock) was generally less than the CO2 wettability of mica at similar physio-thermal conditions. The interfacial data reported in this study are crucial for predicting caprock wettability alterations and the resulting structural sealing capacity for UHS and CGS.
A Review on Application of Hydrogen in Gas Turbines with Intercooler Adjustments
Mar 2024
Publication
In recent years traditional fossil fuels such as coal oil and natural gas have historically dominated various applications but there has been a growing shift towards cleaner alternatives. Among these alternatives hydrogen (H2) stands out as a highly promising substitute for all other conventional fuels. Today hydrogen (H2) is actively taking on a significant role in displacing traditional fuel sources. The utilization of hydrogen in gas turbine (GT) power generation offers a significant advantage in terms of lower greenhouse gas emissions. The performance of hydrogen-based gas turbines is influenced by a range of variables including ambient conditions (temperature and pressure) component efficiency operational parameters and other factors. Additionally incorporating an intercooler into the gas turbine system yields several advantages such as reducing compression work and maintaining power and efficiency. Many scholars and researchers have conducted comprehensive investigations into the components mentioned above within context of gas turbines (GTs). This study provides an extensive examination of the research conducted on hydrogen-powered gas turbine and intercooler with employed different methods and techniques with a specific emphasis on the different case studies of a hydrogen gas turbine and intercooler. Moreover this study not only examined the current state of research on hydrogen-powered gas turbine and intercooler but also covered its influence by offering the effective recommendations and insightful for guiding for future research in this field.
Hydrogen Refueling Infrastructure Design for Personal Mobility Devices using Frugal Engineering Approach
Nov 2012
Publication
More than 150 Hydrogen refueling stations were built around the world in the past 10 years. Much of the technical issues with passenger fuel cell car were discussed and studied. However fuel cell passenger cars are still far from mass production stage. The problem mainly lies with the high cost of fuel cell car production and insufficient hydrogen refueling infrastructure. While the future of fuel cell passenger cars are not clear fuel cell for personal mobility devices like bicycles get more and more attractive. This is mainly due to the simplicity in system design and reducing cost of small size hydrogen fuel cells. But for this technology to be commercialized affordable hydrogen refueling stations is crucial. This study discusses solutions for small sized hydrogen refueling stations based on pressure equalization and simulates the Hydrogen utilization ratio based on different equipment setup. The study is also supported with the experimental data from prototype fuel cell vehicles developed by eMobility in Singapore.
A Review on Biohydrogen Sources, Production Routes, and Its Application as a Fuel Cell
Aug 2023
Publication
More than 80% of the energy from fossil fuels is utilized in homes and industries. Increased use of fossil fuels not only depletes them but also contributes to global warming. By 2050 the usage of fossil fuels will be approximately lower than 80% than it is today. There is no yearly variation in the amount of CO2 in the atmosphere due to soil and land plants. Therefore an alternative source of energy is required to overcome these problems. Biohydrogen is considered to be a renewable source of energy which is useful for electricity generation rather than relying on harmful fossil fuels. Hydrogen can be produced from a variety of sources and technologies and has numerous applications including electricity generation being a clean energy carrier and as an alternative fuel. In this review a detailed elaboration about different kinds of sources involved in biohydrogen production various biohydrogen production routes and their applications in electricity generation is provided.
Carbon Neutrality in Malaysia and Kuala Lumpur: Insights from Stakeholder-driven Integrated Assessment Modelling
Apr 2024
Publication
Introduction: Several cities in Malaysia have established plans to reduce their CO2 emissions in addition to Malaysia submitting a Nationally Determined Contribution to reduce its carbon intensity (against GDP) by 45% in 2030 compared to 2005. Meeting these emissions reduction goals will require ajoint effort between governments industries and corporations at different scales and across sectors.<br/>Methods: In collaboration with national and sub-national stakeholders we developed and used a global integrated assessment model to explore emissions mitigation pathways in Malaysia and Kuala Lumpur. Guided by current climate action plans we created a suite of scenarios to reflect uncertainties in policy ambition level of adoption and implementation for reaching carbon neutrality. Through iterative engagement with all parties we refined the scenarios and focus of the analysis to best meet the stakeholders’ needs.<br/>Results: We found that Malaysia can reduce its carbon intensity and reach carbon neutrality by 2050 and that action in Kuala Lumpur can play a significant role. Decarbonization of the power sector paired with extensive electrification energy efficiency improvements in buildings transportation and industry and the use of advanced technologies such as hydrogen and carbon capture and storage will be Major drivers to mitigate emissions with carbon dioxide removal strategies being key to eliminate residual emissions.<br/>Discussion: Our results suggest a hopeful future for Malaysia’s ability to meet its climate goals recognizing that there may be technological social and financial challenges along the way. This study highlights the participatory process in which stakeholders contributed to the development of the model and guided the analysis as well as insights into Malaysia’s decarbonization potential and the role of multilevel governance.
Comparative Techno-Environmental Assessment of Green Hydrogen Production via Steam Methane Reforming and Chemical Looping Reforming of Biomethane
Aug 2025
Publication
Green hydrogen derived from renewable resources is increasingly recognized as a basis for future low-carbon energy systems. This study presents a comprehensive techno-environmental comparison of two thermochemical conversion pathways utilizing biomethane: steam methane reforming (SMR) and chemical looping reforming (CLR). Through integrated process simulations compositional analyses energy modeling and cost evaluation we examine the comparative advantages of each route in terms of hydrogen yield carbon separation efficiency process energy intensity and economic performance. The results demonstrate that CLR achieves a significantly higher hydrogen concentration in the raw syngas stream (62.44%) than SMR (43.14%) with reduced levels of residual methane and carbon monoxide. The energy requirements for hydrogen production are lower in the CLR system averaging 1.2 MJ/kg compared to 3.2 MJ/kg for SMR. Furthermore CLR offers a lower hydrogen production cost (USD 4.3/kg) compared to SMR (USD 6.4/kg) primarily due to improved thermal integration and the absence of solvent-based CO2 capture. These insights highlight the potential of CLR as a next-generation reforming strategy for producing green hydrogen. To advance its technology readiness it is proposed to develop a pilot-scale CLR facility to validate system performance under operational conditions and support the pathway to commercial implementation.
Enhancing Efficiency in Photovoltaic Hydrogen Production: A Comparative Analysis of MPPT and Electrolysis Control Strategies
Feb 2025
Publication
With the rapid growth of photovoltaic installed capacity photovoltaic hydrogen production can effectively solve the problem of electricity mismatch between new energy output and load demand. Photovoltaic electrolysis systems pose unique challenges due to their nonlinear multivariable and complex nature. This paper presents a thorough investigation into the control methodologies for such systems focusing on both Maximum Power Point Tracking (MPPT) and electrolysis cell control strategies. Beginning with a comprehensive review of MPPT techniques including classical intelligent optimization and hybrid approaches the study delves into the intricate dynamics of Proton Exchange Membrane Electrolysis Cells (PEMEL). Considering the nonlinear and time-varying characteristics of PEMEL various control strategies such as Proportional-Integral-Derivative (PID) robust Model Predictive Control (MPC) and Fault Tolerant Control (FTC) are analyzed. Evaluation metrics encompass stability accuracy computational complexity and response speed. This paper provides a comparative analysis encapsulating the strengths and limitations of each MPPT and PEM control technique.
Feasibility Assessment and Response Surface Optimisation of a Fuel Cell-integrated Sustainable Wind Farm in Italy
Sep 2025
Publication
This study explores the design and feasibility of a novel fuel cell-powered wind farm for residential electricity hydrogen/oxygen production and cooling/heating via a compression chiller. Wind turbine energy powers Proton Exchange Membrane (PEM) electrolyzers and a compression chiller unit. The proposed system was modeled using EES thermodynamic software and its economic viability was assessed. A case study across seven Italian regions with varying wind potentials evaluated the system’s feasibility in diverse weather conditions. Multi-objective optimization using Response Surface Methodology (RSM) determined the number of wind turbines as optimum number of electrolyzers & fuel cell units. Optimization results indicated that 37 wind turbines 1 fuel cell unit and 2 electrolyzer units yielded an exergy efficiency of 27.98 % and a cost rate of 619.9 $/h. TOPSIS analysis suggested 32 wind turbines 2 electrolyzers and 2 reverse osmosis units as an alternative configuration. Further twelve different scenarios were examined to enhance the distribution of wind farmgenerated electricity among the grid electrolyzers and reverse osmosis systems. revealing that directing 25 % to reverse osmosis 20 % to electrolyzers and 55 % to grid sales was optimal. Performance analysis across seven Italian cities (Turin Bologna Florence Palermo Genoa Milan and Rome) identified Genoa Palermo and Bologna as the most suitable locations due to favorable wind conditions. Implementing the system in Genoa the optimal site could produce 28435 MWh of electricity annually prevent 5801 tons of CO2 emissions (equivalent to 139218 $). Moreover selling this clean electricity to the grid could meet the annual clean electricity needs of approximately 5770 people in Italy
Grid Infrastructure and Renewables Integration for Singapore Energy Transition
Oct 2025
Publication
Considering rising environmental concerns and the energy transition towards sustainable energy Singapore’s power sector stands at a crucial juncture. This study explores the integration of grid infrastructure with both generated and imported renewable energy (RE) sources as a strategic pathway for the city-state’s energy transition to reach net-zero carbon emissions by 2050. Employing a combination of simulation modeling and data analysis for energy trading and advanced energy management technologies we examine the current and new grid infrastructure’s capacity to assimilate RE sources particularly solar photovoltaic and energy storage systems. The findings reveal that with strategic upgrades and smart grid technologies; Singapore’s grid can efficiently manage the variability and intermittency of RE sources. This integration is pivotal in achieving a higher penetration of renewables as well as contributing significantly to Singapore’s commitment to the Paris Agreement and sustainable development goals. While the Singapore’s power system has links to the Malay Peninsula the planned ASEAN regional interconnection might alter the grid operation in Singapore and possibly make Singapore a new green energy hub. The study also highlights the key challenges and opportunities associated with cross-border energy trade with ASEAN countries including the need for harmonized regulatory frameworks and incentives to foster public–private partnerships. The insights from this study could guide policymakers industry stakeholders and researchers offering a roadmap for a sustainable energy transition in Singapore towards meeting its 2050 carbon emission goals.
Development of Sustainability Assessment Framework for Preliminary Design of Chemical Process: Hydrogen Production as Case Study
Aug 2025
Publication
Sustainable process design has become increasingly important in transitioning from conventional to sustainable chemical production yet comprehensive sustainability assessment at the preliminary design stage remains a challenge. This study addresses this gap by proposing a hierarchical framework that integrates the Principles Criteria and Indicators (PC&I) method with multi-criteria decision-making (MCDM) tools including entropy weighting TOPSIS and weighted addition. The framework guides the systematic selection of sustainability indicators across economic environmental and social dimensions. To validate its applicability a case study on hydrogen production via four process routes natural gas reforming biomass-derived syngas methanol purge gas recovery and alkaline electrolysis is conducted. Results show that the methanol purge gas process exhibits the best overall sustainability followed by biomass syngas and alkaline electrolysis. The case demonstrates the framework’s capability to differentiate between alternatives under conflicting sustainability dimensions. This work provides a structured and replicable approach to support sustainable decision-making in early-stage chemical process design.
Artificial Intelligence-based Multi-objective Optimization of a Solar-driven System for Hydrogen Production with Integrated Oxygen and Power Co-generation Across Different Climates
Oct 2025
Publication
This study develops and optimizes a solar-powered system for hydrogen generation with oxygen and power coproducts addressing the need for efficient scalable carbon-free energy solutions. The system combines a linear parabolic collector a Steam Rankine cycle and a Proton Exchange Membrane Electrolyzer (PEME) to produce electricity for electrolysis. Thermodynamic modeling was accomplished in Engineering Equation Solver while a hybrid Artificial Intelligence (AI) framework combining Artificial Neural Networks and Genetic Algorithms in Statistica coupled with Technique for Order Preference by Similarity to Ideal Solution (TOPSIS) decision support optimized technical and economic performance. Optimization considered seven key decision variables covering collector design thermodynamic inputs and component efficiencies. The optimization achieved energy and exergy efficiencies of 30.83 % and 26.32 % costing 47.02 USD/h and avoiding CO2 emissions equivalent to 190 USD/ton. Economic and exergy analyses showed the solar and hydrogen units had the highest costs (38.17 USD/h and 9.61 USD/h) with 4503 kWh of exergy destruction to generate 575 kWh of electricity. A case study across six cities suggested that Perth Bunbury and Adelaide with higher solar irradiance delivered the highest annual power and hydrogen outputs consistent with irradiance–electrolyzer correlation. Unlike conventional single-site studies this work delivers a climate-responsive multi-city analysis integrating solar thermal and PEME within an AI-driven framework. By linking techno-economic performance with quantified environmental value and co-production synergies of hydrogen oxygen and electricity the study highlights a novel pathway for scalable clean hydrogen measurable CO2 reductions and global decarbonization with future work focused on digital twins and dynamic uncertainty-aware optimization.
Energy Storage in the Energy Transition and Blue Economy: Challenges, Innovations, Future Perspectives, and Educational Pathways
Sep 2025
Publication
Transitioning to renewable energy is vital to achieving decarbonization at the global level but energy storage is still a major challenge. This review discusses the role of energy storage in the energy transition and the blue economy focusing on technological development challenges and directions. Effective storage is vital for balancing intermittent renewable energy sources like wind solar and marine energy with the power grid. The development of battery technologies hydrogen storage pumped hydro storage and emerging technologies like sodium-ion and metal-air batteries is discussed for their potential for large-scale deployment. Shortages in critical raw materials environmental impact energy loss and costs are some of the challenges to large-scale deployment. The blue economy promises opportunities for offshore energy storage notably through ocean thermal energy conversion (OTEC) and compressed air energy storage (CAES). Moreover the capacity of datadriven optimization and artificial intelligence to enhance storage efficiency is discussed. Policy interventions and economic incentives are necessary to spur the development and deployment of sustainable energy storage technology. Education and workforce training are also important in cultivating future researchers engineers and policymakers with the ability to drive energy innovation. Merging sustainability training with an interdisciplinary approach can potentially establish an efficient workforce that is capable of addressing energy issues. Future work needs to focus on higher energy density efficiency recyclability and cost-effectiveness of the storage technologies without sacrificing their environmental sustainability. The study underlines the need for converging technological economic and educational approaches to enable a sustainable and resilient energy future.
Flexible Economic Energy Management Including Environmental Indices in Heat and Electrical Microgrids Considering Heat Pump with Renewable and Storage Systems
Oct 2025
Publication
This study discusses energy management in thermal and electrical microgrids while taking heat pumps renewable sources thermal and hydrogen storages into account. The weighted total of the operating cost grid emissions level voltage and temperature deviation function and other factors makes up the objective function of the suggested method. The restrictions include the operationflexibility model of resources and storages micro-grid flexibility limits and optimum power flow equations. Point Estimation Method is used in this work to simulate load energy price and renewable phenomenon uncertainty. A fuzzy decision-making methodology is used to arrive at a compromise solution that satisfies network operators’ operational environmental and financial goals. The innovations of this paper include energy management of various smart microgrids simultaneous modeling of several indicators especially flexibility investigation of optimal performance of resources and storage devices and modeling of uncertainty considering low computational time and an accurate flexibility model. Numerical findings indicate that the fuzzy decision-making approach has the capability to reach a compromise point in which the objective functions approach their minimum values. The integration of the proposed uncertainty modeling with precise flexibility modeling results in a reduction in computational time when compared to stochastic optimization based on scenarios. For the compromise point and uncertainty modeling with PEM by efficiently managing resources and thermal and hydrogen storages scheme is capable of attaining high flexibility conditions. Compared to load flow studies the approach can enhance the operational environmental and economic conditions of smart microgrids by approximately 33–57% 68% and 33–68% respectively under these circumstances.
An Integrated AI-driven Framework for Maximizing the Efficiency of Heterostructured Nanomaterials in Photocatalytic Hydrogen Production
Jul 2025
Publication
The urgency for sustainable and efficient hydrogen production has increased interest in heterostructured nanomaterials known for their excellent photocatalytic properties. Traditional synthesis methods often rely on trial-and-error resulting in inefficiencies in material discovery and optimization. This work presents a new AI-driven framework that overcomes these challenges by integrating advanced machine-learning techniques specific to heterostructured nanomaterials. Graph Neural Networks (GNNs) enable accurate representations of atomic structures predicting material properties like bandgap energy and photocatalytic efficiency within ±0.05 eV. Reinforcement Learning optimises synthesis parameters reducing experimental iterations by 40% and boosting hydrogen yield by 15–20%. Physics-Informed Neural Networks (PINNs) successfully predict reaction pathways and intermediate states minimizing synthesis errors by 25%. Variational Autoencoders (VAEs) generate novel material configurations improving photocatalytic efficiency by up to 15%. Additionally Bayesian Optimisation enhances predictive accuracy by 30% through efficient hyperparameter tuning. This holistic framework integrates material design synthesis optimization and experimental validation fostering a synergistic data flow. Ultimately it accelerates the discovery of novel heterostructured nanomaterials enhancing efficiency scalability and yield thus moving closer to sustainable hydrogen production with improvements in photolytic efficiency setting a benchmark for AI-assisted research.
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