Applications & Pathways

The medium- and heavy-duty (MD/HD) vehicle sector is a large emitter of greenhouse gases. It will require drastic emissions reductions to realize a net-zero carbon future. This study conducts fourteen short feasibility investigations in the Canadian context to evaluate the merits of battery electric or hydrogen fuel cell alternatives to conventional city buses inter-city buses school buses courier vehicles (step vans) refuse trucks long-haul trucks and construction vehicles. These “clean transportation alternatives” were evaluated for practicality economics and emission reductions in comparison to their conventional counterparts. Conclusions were drawn on which use cases would be best suited for accelerating the transformation of the MD/HD sector.

Climate change is one of the most serious threats to the human habitat. The required structural change to limit anthropogenic forcing is expected to fundamentally change daily social and economic life. The production of iron and steel is a special case of economic activities since it is not only associated with combustion but particularly with process emissions of greenhouse gases which have to be dealt with likewise. Traditional mitigation options of the sector like efficiency measures substitution with less emission-intensive materials or scrap-based production are bounded and thus insufficient for rapid decarbonization necessary for complying with long-term climate policy targets. Iron and steel products are basic materials at the core of modern socio-economic systems additionally being essential also for other mitigation options like hydro and wind power. Therefore a system-wide assessment of recent technological developments enabling almost complete decarbonization of the sector is substantially relevant. Deploying a recursive-dynamic multi-region multi-sector computable general equilibrium approach we investigate switches from coke-to hydrogen-based iron and steel technologies in a scenario framework where industry decisions (technological choice and timing) and climate policies are mis-aligned. Overall we find that the costs of industry transition are moderate but still ones that may represent a barrier for implementation because the generation deciding on low-carbon technologies and bearing (macro)economic costs might not be the generation benefitting from it. Our macroeconomic assessment further indicates that anticipated bottom-up estimates of required additional domestic renewable electricity tend to be overestimated. Relative price changes in the economy induce electricity substitution effects and trigger increased electricity imports. Sectoral carbon leakage is an imminent risk and calls for aligned course of action of private and public actors.

Tropical climate is characterized by hot temperatures throughout the year. In areas subject to this climate air conditioning represents an important share of total energy consumption. In some tropical islands there is no electric grid; in these cases electricity is often provided by diesel generators. In this study in order to decarbonize electricity and cooling production and to improve autonomy in a standalone application a microgrid producing combined cooling and electrical power was proposed. The presented system was composed of photovoltaic panels a battery an electrolyzer a hydrogen tank a fuel cell power converters a heat pump electrical loads and an adsorption cooling system. Electricity production and storage were provided by photovoltaic panels and a hydrogen storage system respectively while cooling production and storage were achieved using a heat pump and an adsorption cooling system respectively. The standalone application presented was a single house located in Tahiti French Polynesia. In this paper the system as a whole is presented. Then the interaction between each element is described and a model of the system is presented. Thirdly the energy and power management required in order to meet electrical and thermal needs are presented. Then the results of the control strategy are presented. The results showed that the adsorption cooling system provided 53% of the cooling demand. The use of the adsorption cooling system reduced the needed photovoltaic panel area the use of the electrolyzer and the use of the fuel cell by more than 60% and reduced energy losses by 7% (compared to a classic heat pump) for air conditioning.

The glass industry is part of the energy-intensive industry posing a major challenge to fulfill the CO₂ reduction targets of the Paris Climate Agreement. The segments of the glass industry e.g. container or flat glass are quite diverse and attribute to different glass products with different requirements to product quality and various process options. To address the challenge of decarbonizing the glass industry firstly an inventory of current glass products processes and applied technologies in terms of energy efficiency and CO₂ emissions is conducted. Secondly decarbonization options are identified and structured according to fuel substitution waste heat recovery and process intensification. Due to the high share of energy-related CO₂ emissions electrical melting and hydrogen combustion or a combination of both are the most promising options to decarbonize the glass industry but further research design adjustments and process improvements are necessary. Furthermore electricity and hydrogen prices have to decrease or fossil fuels must become more expensive to be cost-competitive relative to fossil fuels and respective infrastructures have to be constructed or adjusted. Various heat recovery options have great potential for CO₂ savings but can be technically challenging or have not yet been considered for techno-economic reasons.

The UK is on course to become a global leader in hydrogen technology. Over £3bn is ready to be invested into hydrogen today. The pace of activity is rapid and the opportunities are vast.



Join us at our free to attend event where you will gain unique insights into how the Hydrogen industry is progressing together with exclusive access to future plans.

The dynamic and lively session will demonstrate the viability of hydrogen as a key component to achieve Net Zero.



Confirmed contributors include:

• National Grid Gas Transmission
• Cadent
• Chris Train Previous CEO Cadent
• DNV
• Worcester Bosch
• ITM Power
• Northern Gas Networks
• Decarbonising Heat in Buildings - New Research Findings from the Gas Distribution Networks

This paper discusses the numerical modeling of an automobile fuel cell system using a two-stage turbo-compressor for air supply. The numerical model incorporates essential input parameters for air and hydrogen flow. The model also performed mass and energy balances across different components such as pump fan heat-exchanger air compressor and keeps in consideration the pressure losses across flow pipes and various mechanical parts. The compressor design process initiates with numerical analysis of the preliminary design of a highly efficient two-stage turbo compressor with an expander as a single-stage compressor has several limitations in terms of efficiency and pressure ratio. The compressor’s design parameters were carefully studied and analyzed with respect to the highly efficient fuel cell stack (FCS) used in modern hydrogen vehicles. The model is solved to evaluate the overall performance of PEM FCS. The final compressor has a total pressure and temperature of 4.2 bar and 149.3°C whereas the required power is 20.08kW with 3.18kW power losses and having a combined efficiency of 70.8%. According to the FC model with and without expander the net-power outputs are 98.15kW and 88.27kW respectively and the maximum efficiencies are 65.1% and 59.1% respectively. Therefore it can be concluded that a two-stage turbo compressor with a turbo-expander can have significant effects on overall system power and efficiency. The model can be used to predict and optimize system performance for PEM FCS at different operating conditions.

Densified liquid hydrogen/liquid oxygen is a promising propulsion fuel in the future. In order to systematically demonstrate the benefits and challenges of densified liquid hydrogen/liquid oxygen a transient thermodynamical model considering the heat leakage temperature rise engine thrust pressurization pressure of the tank and wall thickness of tank is developed in the present paper and the performance of densified liquid hydrogen/liquid oxygen as propulsion fuel is further evaluated in actual application. For liquid hydrogen/liquid oxygen tanks at different structural dimensions the effects of many factors such as temperature rise during propellant ground parking lift of engine thrust mass reduction of the tank structure and extension of spacecraft in‐orbit time are analyzed to demonstrate the comprehensive performance of liquid hydrogen/liquid oxygen after densification. Meanwhile the problem of subcooling combination matching of liquid hydro‐ gen/liquid oxygen is proposed for the first time. Combining the fuel consumption and engine thrust lifting the subcooling combination matching of liquid hydrogen/liquid oxygen at different mixing ratios and constant mixing ratios are discussed respectively. The results show that the relative engine thrust enhances by 6.96% compared with the normal boiling point state in the condition of slush hydrogen with 50% solid content and enough liquid oxygen. The in‐orbit time of spacecraft can extend about 2–6.5 days and 24–95 days for slush hydrogen with 50% solid content and liquid oxygen in the triple point state in different cryogenic tanks respectively. Due to temperature rise during parking the existing adiabatic storage scheme and filling scheme for densification LH2 need to be redesigned and for densification LO2 are suitable. It is found that there is an optimal subcooling matching relation after densification of liquid hydrogen/liquid oxygen as propulsion fuel. In other words the subcooling temperature of liquid hydrogen/liquid oxygen is not the lower the bet‐ ter but the matching relationship between LH2 subcooling degree and LO2 subcooling degree needs to be considered at the same time. It is necessary that the LO2 was cooled to 69.2 K and 54.5 K when the LH2 of 13.9 K and SH2 with 45% was adopted respectively. This research provides theoretical support for the promotion and application of densification cryogenic propellants.

Managing the concentration of atmospheric CO₂ requires a multifaceted engineering strategy which remains a highly challenging task. Reducing atmospheric CO₂ (CO2R) by converting it to value-added chemicals in a carbon neutral footprint manner must be the ultimate goal. The latest progress in CO2R through either abiotic (artificial catalysts) or biotic (natural enzymes) processes is reviewed herein. Abiotic CO2R can be conducted in the aqueous phase that usually leads to the formation of a mixture of CO formic acid and hydrogen. By contrast a wide spectrum of hydrocarbon species is often observed by abiotic CO2R in the gaseous phase. On the other hand biotic CO2R is often conducted in the aqueous phase and a wide spectrum of value-added chemicals are obtained. Key to the success of the abiotic process is understanding the surface chemistry of catalysts which significantly governs the reactivity and selectivity of CO2R. However in biotic CO2R operation conditions and reactor design are crucial to reaching a neutral carbon footprint. Future research needs to look toward neutral or even negative carbon footprint CO2R processes. Having a deep insight into the scientific and technological aspect of both abiotic and biotic CO2R would advance in designing efficient catalysts and microalgae farming systems. Integrating the abiotic and biotic CO2R such as microbial fuel cells further diversifies the spectrum of CO2R.

A research is under development at the Department of Agro-Environmental Sciences of the University of Bari “Aldo Moro” in order to investigate the suitable solutions of a power system based on solar energy (photovoltaic) and hydrogen integrated with a geothermal heat pump for powering a self sustained heated greenhouse. The electrical energy for heat pump operation is provided by a purpose-built array of solar photovoltaic modules which supplies also a water electrolyser system controlled by embedded pc; the generated dry hydrogen gas is conserved in suitable pressured storage tank. The hydrogen is used to produce electricity in a fuel cell in order to meet the above mentioned heat pump power demand when the photovoltaic system is inactive during winter night-time or the solar radiation level is insufficient to meet the electrical demand. The present work reports some theoretical and observed data about the electrolyzer operation. Indeed the electrolyzer has required particular attention because during the experimental tests it did not show a stable operation and it was registered a performance not properly consistent with the predicted performance by means of the theoretical study.

Our new independent report finds that hydrogen can play an important role in UK’s ambitious decarbonisation plan and boost its global industrial competitiveness.

Key insights from this new analysis include:

• New independent report from Aurora Energy Research shows that hydrogen can meet up to half of Great Britain’s (GB) final energy demand by 2050 providing an important pathway to reaching UK’s ambitious Net Zero targets.
• The report concludes that both blue hydrogen (produced from natural gas after reforming to remove carbon content) and green hydrogen (produced by using power to electrolyse water) are expected to play an important role providing up to 480TWh of hydrogen or c.45% of GB’s final energy demand by 2050.
• All Net Zero scenarios require substantial growth in low-carbon generation such as renewables and nuclear. Large-scale hydrogen adoption could help to integrate renewables into the power system by reducing the power sector requirement for flexibility during peak winter months and boosting revenues for clean power generators by c. £3bn per year by 2050.
• The rollout of hydrogen could accelerate green growth and enable the development of globally competitive low-carbon industrial clusters while utilising UK’s competitive advantage on carbon capture.
• In facilitating the identification of a cost-effective hydrogen pathway there are some low-regret options for Government to explore including the stimulation of hydrogen demand in key sectors the deployment of CCS in strategic locations and the standardisation of networks. These initiatives could form an important part of the UK Government’s post-COVID stimulus plan.

Read the full report on Aurora Energy Research Website

This report summarizes the work conducted under U.S. Department of Energy (DOE) under contract DE-FC36-04GO14285 by Mercedes-Benz & Research Development North America (MBRDNA) Chrysler Daimler Mercedes Benz USA (MBUSA) BP DTE Energy and NextEnergy to validate fuel cell technologies for infrastructure transportation as well as assess technology and commercial readiness for the market. The Mercedes Team together with its partners tested the technology by operating and fuelling hydrogen fuel cell vehicles under real world conditions in varying climate terrain and driving conditions. Vehicle and infrastructure data was collected to monitor the progress toward the hydrogen vehicle and infrastructure performance targets of $2.00 to 3.00/gge hydrogen production cost and 2000-hour fuel cell durability. Finally to prepare the public for a hydrogen economy outreach activities were designed to promote awareness and acceptance of hydrogen technology. DTE BP and NextEnergy established hydrogen filling stations using multiple technologies for on-site hydrogen generation storage and dispensing. DTE established a hydrogen station in Southfield Michigan while NextEnergy and BP worked together to construct one hydrogen station in Detroit. BP constructed another fueling station in Burbank California and provided a full-time hydrogen trailer at San Francisco California and a hydrogen station located at Los Angeles International Airportmore.

Considering a simple regenerative Brayton cycle the impact of using different fuel blends containing a variable volumetric percentage of hydrogen in methane was analysed. Due to the potential of hydrogen combustion in gas turbines to reduce the overall CO2 emissions and the dependency on natural gas further research is needed to understand the impact on the overall thermodynamic cycle. For that purpose a qualitative thermodynamic analysis was carried out to assess the exergetic and energetic efficiencies of the cycle as well as the irreversibilities associated to a subsystem. A single step reaction was considered in the hypothesis of complete combustion of a generic H2/CH4 mixture where the volumetric H2 percentage was represented by fH2 which was varied from 0 to 1 defining the amount of hydrogen in the fuel mixture. Energy and entropy balances were solved through the Engineering Equation Solver (EES) code. Results showed that global exergetic and energetic efficiencies increased by 5% and 2% respectively varying fH2 from 0 to 1. Higher hydrogen percentages resulted in lower exergy destruction in the chamber despite the higher air-excess levels. It was also observed that higher values of fH2 led to lower fuel mass flow rates in the chamber showing that hydrogen can still be competitive even though its cost per unit mass is twice that of natural gas.

The target for European decarburization encourages the use of renewable energy sources and H₂ is considered the link in the global energy system transformation. So research studies are numerous but only few facilities can test materials and components for H₂ storage. This work offers a brief review of H₂ storage methods and presents the preliminary results obtained in a new facility. Slow strain rate and fatigue life tests were performed in H₂ at 80 MPa on specimens and a tank of AISI 4145 respectively. Besides the storage capacity at 30 MPa of a solid-state system they were evaluated on kg scale by adsorption test. The results have shown the H₂ influence on mechanical properties of the steel. The adsorption test showed a gain of 26% at 12 MPa in H₂ storage with respect to the empty condition. All samples have been characterized by complementary techniques in order to connect the H2 effect with material properties.

In the last two years or so there has been increasing interest in hydrogen as an energy source in Australia and around the world. Notably this is not the first time that hydrogen has caught our collective interest. Most recently the 2000s saw a substantial investment in hydrogen research development and demonstration around the world. Prior to that the oil crises of the 1970s also stimulated significant investment in hydrogen and earlier still the literature on hydrogen was not lacking. And yet the hydrogen economy is still an idea only.<br/>So what if anything might be different this time?<br/>This is an important question that we all need to ask and for which the author can only give two potential answers. First our need to make dramatic reductions in greenhouse gas (GHG) emissions has become more pressing since these previous waves of interest. Second renewable energy is considerably more affordable now than it was before and it has consistently outperformed expectations in terms of cost reductions by even its strongest supporters.<br/>While this dramatic and ongoing reduction in the cost of renewables is very promising our need to achieve substantial GHG emission reductions is the crucial challenge. Moreover meeting this challenge needs to be achieved with as little adverse social and economic impact as possible.<br/>When considering what role hydrogen might play we should first think carefully about the massive scale and complexity of our global energy system and the typical prices of the major energy commodities. This provides insights into what opportunities hydrogen may have. Considering a temperate country with a small population like Australia we see that domestic natural gas and transport fuel markets are comparable to and even larger than the electricity market on an energy basis.

The virtual energy storage system (VESS) is one of the emerging novel concepts among current energy storage systems (ESSs) due to the high effectiveness and reliability. In fact VESS could store surplus energy and inject the energy during the shortages at high power with larger capacities compared to the conventional ESSs in smart grids. This study investigates the optimal operation of a multi-carrier VESS including batteries thermal energy storage (TES) systems power to hydrogen (P2H) and hydrogen to power (H2P) technologies in hydrogen storage systems (HSS) and electric vehicles (EVs) in dynamic ESS. Further demand response program (DRP) for electrical and thermal loads has been considered as a tool of VESS due to the similar behavior of physical ESS. In the market three participants have considered such as electrical thermal and hydrogen markets. In addition the price uncertainties were calculated by means of scenarios as in stochastic programming while the optimization process and the operational constraints were considered to calculate the operational costs in different ESSs. However congestion in the power systems is often occurred due to the extreme load increments. Hence this study proposes a bi-level formulation system where independent system operators (ISO) manage the congestion in the upper level while VESS operators deal with the financial goals in the lower level. Moreover four case studies have considered to observe the effectiveness of each storage system and the simulation was modeled in the IEEE 33-bus system with CPLEX in GAMS.

We combine previously separate models of Northern European power markets local district heating and cooling (DHC²) systems and biomass supply in a single modelling framework to study local and system level impacts of bioenergy technologies in phasing out fossil fuels from a DHC system of the Finnish capital. We model multiple future scenarios and assess the impacts on energy security flexibility provision economic performance and emissions. In the case of Helsinki heat only boiler is a robust solution from economic and climate perspective but reduces local electricity self-sufficiency. Combined heat and power solution is more valuable investment for the system than for the city indicating a conflict of interest and biased results in system level models. Bringing a biorefinery near the city to utilize excess heat would reduce emissions and increase investment's profitability but biomass availability might be a bigger limiting factor. Our results show that the availability of domestic biomass resources constrains bio-based technologies in Southern Finland and further highlights the importance of considering both local and system level impacts. Novel option to boost biorefinery's production with hydrogen from excess electricity is beneficial with increasing shares of wind power.

The diffusion of electric vehicles in Italy has started but some complications weight its spread. At present hybrid technology is the most followed by users due particularly to socioeconomic factors such as cost of investment and range anxiety. After a deep discussion of the Italian scenario the aim of the paper is to recognize whether fuel cell technology may be an enabling solution to overcome pollution problems and respect for the environment. The opportunity to use fuel cells to store electric energy is quite fascinating—the charging times will be shortened and heavy passenger transport should be effortless challenged. On the basis of the present history and by investigating the available information this work reports the current e-mobility state in Italy and forecasts the cities in which a fuel cell charging infrastructure should be more profitable with the intention of granting a measured outlook on the plausible development of this actual niche market.

Due to the low efficiency and high pollution of conventional internal combustion engine vehicles the fuel cell hybrid electric vehicles are expected to play a key role in the future of clean energy transportation attributed to the long driving range short hydrogen refueling time and environmental advantages. The development of energy management strategies has an important impact on the economy and durability but most strategies ignore the aging of fuel cells and the corresponding impact on hydrogen consumption. In this paper a rule-based fuzzy control strategy is proposed based on the constructed data-driven online estimation model of fuel cell health. Then a genetic algorithm is used to optimize this fuzzy controller where the objective function is designed to consider both the economy and durability by combining the hydrogen consumption cost and the degradation cost characterized by the fuel cell health status. Considering that the rule-based strategy is more sensitive to operating conditions this paper uses an artificial neural network for predictive control. The results are compared with those obtained from the genetic algorithm optimized fuzzy controller and are found to be very similar where the prediction accuracy is assessed using MAPE RMSE and 10-fold cross-validation. Experiments show that the developed strategy has a good generalization capability for variable driving cycles.

Integrated water electrolysis is a core principle of new process configurations for decarbonized heavy industries. Water electrolysis generates H2 and O2 and involves an exchange of thermal energy. In this manuscript we investigate specific traditional heavy industrial processes that have previously been performed in nitrogen-rich air environments. We show that the individual process streams may be holistically integrated to establish new decarbonized industrial processes. In new process configurations CO2 capture is facilitated by avoiding inert gases in reactant streams. The primary energy required to drive electrolysis may be obtained from emerging renewable power sources (wind solar etc.) which have enjoyed substantial industrial development and cost reductions over the last decade. The new industrial designs uniquely harmonize the intermittency of renewable energy allowing chemical energy storage. We show that fully integrated electrolysis promotes the viability of decarbonized industrial processes. Specifically new process designs uniquely exploit intermittent renewable energy for CO2 conversion enabling thermal integration H2 and O2 utilization and sub-process harmonization for economic feasibility. The new designs are increasingly viable for decarbonizing ferric iron reduction municipal waste incineration biomass gasification fermentation pulp production biogas upgrading and calcination and are an essential step forward in reducing anthropogenic CO2 emissions.

Driven by a small number of niche markets and several decades of application research fuel cell systems (FCS) are gradually reaching maturity to the point where many players are questioning the interest and intensity of its deployment in the transport sector in general. This article aims to shed light on this debate from the road transport perspective. It focuses on the description of the fuel cell vehicle (FCV) in order to understand its assets limitations and current paths of progress. These vehicles are basically hybrid systems combining a fuel cell and a lithium-ion battery and different architectures are emerging among manufacturers who adopt very different levels of hybridization. The main opportunity of Fuel Cell Vehicles is clearly their design versatility based on the decoupling of the choice of the number of Fuel Cell modules and hydrogen tanks. This enables manufacturers to meet various specifications using standard products. Upcoming developments will be in line with the crucial advantage of Fuel Cell Vehicles: intensive use in terms of driving range and load capacity. Over the next few decades long-distance heavy-duty vehicles and fleets of taxis or delivery vehicles will develop based on range extender or mild hybrid architectures and enable the hydrogen sector to mature the technology from niche markets to a large-scale market.

The upcoming stricter limitations on both pollutant and greenhouse gases emissions represent a challenge for the shipping sector. The entire ship design process requires an approach to innovation with a particular focus on both the fuel choice and the power generation system. Among the possible alternatives natural gas and hydrogen based propulsion systems seem to be promising in the medium and long term. Nonetheless natural gas and hydrogen storage still represents a problem in terms of cargo volume reduction. This paper focuses on the storage issue considering compressed gases and presents an innovative solution which has been developed in the European project GASVESSEL® that allows to store gaseous fuels with an energy density higher than conventional intermediate pressure containment systems. After a general overview of natural gas and hydrogen as fuels for shipping a case study of a small Roll-on/Rolloff passenger ferry retrofit is proposed. The study analyses the technical feasibility of the installation of a hybrid power system with batteries and polymer electrolyte membrane fuel cells fuelled by hydrogen. In particular a process simulation model has been implemented to assess the quantity of hydrogen that can be stored on board taking into account boundary conditions such as filling time on shore storage capacity and cylinder wall temperature. The simulation results show that if the fuel cells system is run continuously at steady state to cover the energy need for one day of operation 140 kg of hydrogen are required. Using the innovative pressure cylinder at a storage pressure of 300 bar the volume required by the storage system assessed on the basis of the containment system outer dimensions is resulted to be 15.2 m3 with a weight of 2.5 ton. Even if the innovative type of pressure cylinder allows to reach an energy density higher than conventional intermediate pressure cylinders the volume necessary to store a quantity of energy typical for the shipping sector is many times higher than that required by conventional fuels today used. The analysis points out as expected that the filling process is critical to maximize the stored hydrogen mass and that it is critical to measure the temperature of the cylinder walls in order not to exceed the material limits. Nevertheless for specific application such as the one considered in the paper the introduction of gaseous hydrogen as fuel can be considered for implementing zero local emission propulsion system in the medium term.

Fuel cell electric vehicles (FCEVs) can play a key role in accelerating the electrification of road transport. Specifically they offer longer driving ranges and shorter refuelling times relative to Battery Electric Vehicles (BEVs) while reducing needs for space-intensive public charging infrastructure. Although the maturity and market penetration of hydrogen is currently trailing batteries transport planners in several countries are looking to both technologies to reduce carbon emissions and air pollution. Home to the world’s largest on-road fleet of FCEVs California is one such jurisdiction. Experiences in California provide an ideal opportunity to address a gap in literature whereby barriers to FCEV diffusion are well understood but knowledge on actual strategies to overcome these has lacked. This study thus examines governance strategies in California to accelerate the production and diffusion of FCEVs key outcomes lessons learned and unresolved challenges. Evidence is sourced from 19 expert interviews and an examination of diverse documents. Strategies are examined from four perspectives: (i) supply-side (i.e. stimulation of vehicle production) (ii) infrastructure (i.e. construction of refuelling stations and hydrogen production) (iii) demand-side (i.e. stimulation of vehicle adoption) and (iv) institutional (i.e. cross-cutting measures to facilitate collaboration innovation and cost-reduction). Findings reveal a comprehensive mix of stringent regulation market and consumer incentives and public–private collaboration. However significant challenges remain for spurring the development of fuel cell transport in line with initial ambitions. Highlighting these provides important cues for public policy to accelerate the deployment of FCEVs and hydrogen in California and elsewhere.

The UK government heat strategy is partially based on decarbonisation pathways from the UK MARKAL energy system model. We review how heat provision is represented in UK MARKAL identifying a number of shortcomings and areas for improvement. We present a completely revised model with improved estimations of future heat demands and a consistent representation of all heat generation technologies. This model represents all heat delivery infrastructure for the first time and uses dynamic growth constraints to improve the modelling of transitions according to innovation theory. Our revised model incorporates a simplified housing stock model which is used produce highly-refined decarbonisation pathways for residential heat provision. We compare this disaggregated model against an aggregated equivalent which is similar to the existing approach in UK MARKAL. Disaggregating does not greatly change the total residential fuel consumption in two scenarios so the benefits of disaggregation will likely be limited if the focus of a study is elsewhere. Yet for studies of residential heat disaggregation enables us to vary consumer behaviour and government policies on different house types as well as highlighting different technology trends across the stock in comparison with previous aggregated versions of the model.

A greenhouse containing an integrated system of photovoltaic panels a water electrolyzer fuel cells and a geothermal heat pump was set up to investigate suitable solutions for a power system based on solar energy and hydrogen feeding a self-sufficient geothermal-heated greenhouse. The electricity produced by the photovoltaic source supplies the electrolyzer; the manufactured hydrogen gas is held in a pressure tank. In these systems the electrolyzer is a crucial component; the technical challenge is to make it work regularly despite the irregularity of the solar source. The focus of this paper is to study the performance and the real energy efficiency of the electrolyzer analyzing its operational data collected under different operating conditions affected by the changeable solar radiant energy characterizing the site where the experimental plant was located. The analysis of the measured values allowed evaluation of its suitability for the agricultural requirements such as greenhouse heating. On the strength of the obtained result a new layout of the battery bank has been designed and exemplified to improve the performance of the electrolyzer. The evaluations resulting from this case study may have a genuine value therefore assisting in further studies to better understand these devices and their associated technologies.

The approach developed aims to identify the methodology that will be used to deliver the minimum cost for hydrogen infrastructure deployment using a mono-objective linear optimisation. It focuses on minimizing both capital and operation costs of the hydrogen transportation based on transportation via truck which represents the main focus of this paper and a cost-minimal pipeline system in the case of France and Germany. The paper explains the mathematical model describing the link between the hydrogen production via electrolysers and the distribution for mobility needs. The main parameters and the assumed scenario framework are explained. Subsequently the transportation of hydrogen via truck using different states of aggregation is analysed as well as the transformation and storage of hydrogen. This is used finally to build a linear programming aiming to minimize the sum of costs of hydrogen transportation between the different nodes and transformation/storage within the nodes.