Applications & Pathways

The growing concern about climate change and the contemporary increase in mobility requirements call for faster cheaper safer and cleaner means of transportation. The retrofitting of fossil-fueled piston engine ultralight aerial vehicles to hydrogen power systems is an option recently proposed in this direction. The goal of this investigation is a comparative analysis of the environmental impact of conventional and hydrogen-based propulsive systems. As a case study a hybrid electric configuration consisting of a fuel cell with a nominal power of about 30 kW a 6 kWh LFP battery and a pressurized hydrogen vessel is proposed to replace a piston prop configuration for an ultralight aerial vehicle. Both power systems are modeled with a backward approach that allows the efficiency of the main components to be evaluated based on the load and altitude at every moment of the flight with a time step of 1 s. A typical 90 min flight mission is considered for the comparative analysis which is performed in terms of direct and indirect emissions of carbon dioxide water and pollutant substances. For the hydrogen-based configuration two possible strategies are adopted for the use of the battery: charge sustaining and charge depleting. Moreover the effect of the altitude on the parasitic power of the fuel cell compressor and consequently on the net efficiency of the fuel cell system is taken into account. The results showed that even if the use of hydrogen confines the direct environmental impact to the emission of water (in a similar quantity to the fossil fuel case) the indirect emissions associated with the production transportation and delivery of hydrogen and electricity compromise the desired achievement of pollutant-free propulsion in terms of equivalent emissions of CO2 and VOCs if hydrogen is obtained from natural gas reforming. However in the case of green hydrogen from electrolysis with wind energy the total (direct and indirect) emissions of CO2 can be reduced up to 1/5 of the fossil fuel case. The proposed configuration has the additional advantage of eliminating the problem of lead which is used as an additive in the AVGAS 100LL.

Wind and solar energy are the important renewable energy sources while their inherent natures of random and intermittent also exert negative effect on the electrical grid connection. As one of multiple energy complementary route by adopting the electrolysis technology the wind-solar-hydrogen hybrid system contributes to improving green power utilization and reducing its fluctuation. Therefore the moving average method and the hybrid energy storage module are proposed which can smooth the wind-solar power generation and enhance the system energy management. Moreover the optimization of system capacity configuration and the sensitive analysis are implemented by the MATLAB program platform. The results indicate that the 10-min grid-connected volatility is reduced by 38.7% based on the smoothing strategy and the internal investment return rate can reach 13.67% when the electricity price is 0.04 $/kWh. In addition the annual coordinated power and cycle proportion of the hybrid energy storage module are 80.5% and 90% respectively. The developed hybrid energy storage module can well meet the annual coordination requirements and has lower levelized cost of electricity. This method provides reasonable reference for designing and optimizing the wind-solar-hydrogen complementary system.

The world’s economy heavily depends on the energy resources used by various countries. India is one of the promising developing nations with very low crude reserves actively looking for new renewable energy resources to power its economy. Higher energy consumption and environmental pollution are two big global challenges for our sustainable development. The world is currently facing a dual problem of an energy crisis as well as environmental degradation. So there is a strong need to reduce our dependency on fossil fuels and greenhouse gas emissions. This can be achieved to a great extent by universally adopting clean fuels for all daily life uses like ethanol or liquified natural gas (LNG) as these burn very clean and do not emit many pollutants. Nowadays green hydrogen has emerged as a new clean energy source which is abundantly available and does not pollute much. This article explores the various benefits of green hydrogen with respect to fossil fuels various techniques of producing it and its possible use in different sectors such as industry transport and aviation as well as in day-to-day life. Finally it explores the use of green hydrogen as fuel in automobile engines its blending with CNG gas and its benefits in reducing emissions compared to fossil fuels. On combustion green hydrogen produces only water vapours and is thus a highly clean fuel. Thus it can potentially help humanity preserve the environment due to its ultra-low emissions and can be a consistent and reliable source of energy for generations to come thereby ending the clean energy security debate forever.

Decarbonising and decontaminating remote regions in the world presents several challenges. Many of these regions feature isolation dispersed demand in large areas and a lack of economic resources that impede the development of robust and sustainable networks. Furthermore isolated systems in the developing world are mostly based on diesel generation for electricity and firewood and liquefied petroleum gas for heating as these options do not require a significant infrastructure cost. In this context we present a stochastic multi-energy multi-microgrid system planning model that integrates electricity heat and hydrogen networks in isolated systems. The model is stochastic to capture uncertainty in renewable generation outputs particularly hydro and wind and thus design a multi-energy system proved secured against such uncertainty. The model also features two distinct constraints to limit the emissions of CO2 (for decarbonisation) and particulate matter (for decontamination) and incorporates firewood as a heating source. Moreover given that the focus is on low-voltage networks we introduce a fully linear AC power flow equations set allowing the planning model to remain tractable. The model is applied to a real-world case study to design a multi-energy multi-microgrid system in an isolated region in Chilean Patagonia. In a case with a zero limit over direct CO2 emissions the total system’s cost increases by 34% with respect to an unconstrained case. In a case with a zero limit over particulate matter emissions the total system’s cost increases by 189%. Finally although an absolute zero limit over both particulate matter and direct CO2 emissions leads to a total system’s cost increase of 650% important benefits in terms of decarbonisation and decontamination can be achieved at marginal cost increments.

In view of the GHG reduction targets to be met Brazilian researchers are looking for cleaner alternatives to energy sources. These alternatives are primarily to be applied in the transport sector which presents high energy consumption as well as high CO2 emissions. In this sense this research developed an LCI study considering two bus alternatives for the city of Rio de Janeiro: diesel-powered internal combustion buses (ICEB) and a hydrogen-powered polymer fuel cell hybrid bus (FCHB). For the FCHB three hydrogen production methods were also included: water electrolysis (WE) ethanol steam reforming (ESR) and natural gas steam reforming (NGSR). The research was aimed at estimating energy consumption including the percentage of energy that is renewable as well as CO2 emissions. The results show diesel as the energy source with the highest emissions as well as the highest fossil energy consumption. Regarding the alternatives for hydrogen production water electrolysis stood out with the lowest emissions.

The member countries of the European Union (EU) have prioritized the incorporation of hydrogen as a key component of their energy objectives. As the world moves towards reducing its dependence on fossil fuels alternative sources of energy have gained prominence. With the growing development of Fuel Cell Electric Vehicles (FCEVs) the establishment of an infrastructure for hydrogen production and the creation of a network of service stations have become essential. This article’s purpose is to conduct a methodical review of literature regarding the use of green hydrogen for transportation and the planning of imperative infrastructure in the territory of the EU specifically Hydrogen Refueling Stations (HRS). In order to increase the acceptance of fuel cell vehicles a comprehensive network of hydrogen refueling stations (HRS) must be built that enable drivers to refuel their vehicles quickly and easily similar to gasoline or diesel vehicles. The literature review on this topic was conducted using the Web of Science database (WOS) with a variety of search terms proposed to cover all the key components of green hydrogen production and refueling infrastructure. The implementation of HRS powered by renewable energy sources is an important step in the adoption of fuel cell vehicles and overcoming the obstacles that come with their implementation will require cooperation and innovation from governments private businesses and other stakeholders.

Shifting from fossil fuels to clean alternative fuel options such as hydrogen is an essential step in decarbonising the road freight transport sector and facilitating an efficient transition towards zero-emissions goods distribution of the future. Designing an economically viable and competitive Hydrogen Supply Chain (HSC) to support and accelerate the widespread adoption of hydrogen powered Heavy Goods Vehicles (H2-HGVs) is however significantly hindered by the lack of the infrastructure required for producing storing transporting and distributing the required hydrogen. This paper focuses on a bespoke design of a hydrogen supply chain and distribution network for the long-haul road freight transportation in the UK and develops an improved end-to-end and spatially-explicit optimisation tool to perform scenario analysis and provide important first-hand managerial and policy making insights. The proposed methodology improves over existing grid-based methodologies by incorporating spatially-explicit locations of Hydrogen Refuelling Stations (HRSs) and allowing further flexibility and accuracy. Another distinctive feature of the method and the analyses carried out in the paper pertains to the inclusion of bulk geographically agnostic as well as geological underground hydrogen storage options and reporting on significant cost saving opportunities. Finally the curve for H2-HGVs penetration levels safety stock period decisions and the transport mode capacity against hydrogen levelized cost at pump have been generated as important policy making tools to provide decision support and insights into cost resilience and reliability of the HSC.

With the aggravation of global environmental pollution problems and the need for energy restructuring hydrogen energy as a highly clean resource has gradually become a hot spot for research in countries around the world. Facing the requirement of distributed hydrogen in refueling the original station for hydrogen transportation and other usage this paper proposes a comprehensive energy system planning model for hydrogen refueling stations to obtain the necessary devices construction the devices’ capacity decisions and the optimal operation behaviors of each device. Comparing to traditional single hydrogen producing technics in the traditional planning model the proposed model in this paper integrates both water-electrolysis-based and methanol-based manufacturing technics. A two-level optimization model is designed for this comprehensive system. The result of the numerical study shows that the proposed model can achieve a better optimal solution for distributed hydrogen production. Also it considers the single producing situation when price of one primary resource is sufficient higher than the other.

Airlines are faced with the challenge of reducing their environmental footprint in an effort to push for climate-neutral initiatives that comply with international regulations. In the past the aviation industry has followed the approach of incremental improvement of fuel efficiency while simultaneously experiencing significant growth in annual air traffic. With the increase in air traffic negating any reduction in Greenhouse Gas (GHG) emissions more disruptive technologies such as hydrogen-based onboard power generation are required to reduce the environmental impact of airline operations. However despite initial euphoria and first conceptual studies for hydrogen-powered aircraft several decades ago there still has been no mass adoption to this day. Besides the challenges of a suitable ground infrastructure this can partly be attributed to uncertainties with the associated maintenance requirements and the expected operating costs to demonstrate the economic viability of this technology. With this study we address this knowledge gap by estimating changes towards scheduled maintenance activities for an airborne hydrogen storage and distribution system. In particular we develop a detailed system design for a hydrogen-powered fuel-cell-based auxiliary power generation and perform a comparative analysis with an Airbus A320 legacy system. That analysis allows us to (a) identify changes for the expected maintenance effort to enhance subsequent techno-economic assessments (b) identify implications of specific design assumptions with corresponding maintenance activities while ensuring regulatory compliance and (c) describe the impact on the resulting task execution. The thoroughly examined interactions between system design and subsequent maintenance requirements of this study can support practitioners in the development of prospective hydrogen-powered aircraft. In particular it allows the inclusion of maintenance implications in early design stages of corresponding system architectures. Furthermore since the presented methodology is transferable to different design solutions it provides a blueprint for alternative operating concepts such as the complete substitution of kerosene by hydrogen to power the main engines.

This study proposes a predictive equivalent consumption minimization strategy (P-ECMS) that utilizes velocity prediction and considers various dynamic constraints to mitigate fuel cell degradation assessed using a dedicated sub-model. The objective is to reduce fuel consumption in real-world conditions without prior knowledge of the driving mission. The P-ECMS incorporates a velocity prediction layer into the Energy Management System. Comparative evaluations with a conventional adaptive-ECMS (A-ECMS) a standard ECMS with a well-tuned constant equivalence factor and a rule-based strategy (RBS) are conducted across two driving cycles and three fuel cell dynamic restrictions (|∕| ≤ 0.1 0.01 and 0.001 A∕cm2 ). The proposed strategy achieves H2 consumption reductions ranging from 1.4% to 3.0% compared to A-ECMS and fuel consumption reductions of up to 6.1% when compared to RBS. Increasing dynamic limitations lead to increased H2 consumption and durability by up to 200% for all tested strategies.