Applications & Pathways

Hydrogen and fuel cell technologies have experienced cycles of high expectations followed by impractical realities. This time around however falling renewable energy and fuel cell prices stringent climate change requirements and the discrete involvement of China are step changes. The combination of these factors is leading to realistic potential for hydrogen’s role in the Grand Transition.<br/>Having conducted exploratory interviews with leaders from all around the globe the World Energy Council is featuring eight use cases which illustrate hydrogen’s potential. These range from decarbonising hard-to-abate sectors such as heat industry and transport to supporting the integration of renewables and providing an energy storage solution.<br/>Dr Angela Wilkinson Secretary General and former Senior Director Scenarios and Business Insights: “Green and blue hydrogen can refresh those parts of the energy system transition that electrification cannot reach.”<br/>This Innovation Insights Brief is part of a series of publications by the World Energy Council focused on Innovation. In a fast-paced era of disruptive changes this brief aims at facilitating strategic sharing of knowledge between the Council’s members and the other energy stakeholders and policy shapers.

With the application of new energy technology hybrid agricultural machinery has been developed. This article designs a hybrid tractor energy management method to solve the problem of high energy consumption caused by significant load fluctuation of the tractor in field operation. This article first analyzes the characteristics of the hydrogen fuel cell power battery and ultracapacitor and designs a hybrid energy system for the tractor. Second the energy management strategy (EMS) of multi-layer decoupling control based on the Haar wavelet and logic rule is designed to realize the multi-layer decoupling of high-frequency low-frequency and steady-state signals of load demand power. Then the EMS redistributes the decoupled power signals to each energy source. Finally a hardware-in-loop simulation experiment was carried out through the model. The results show that compared with single-layer control strategies such as fuzzy control and power-following control the multi-layer control strategy can allocate the demand power more reasonably and the efficiency of the hydrogen fuel cell is the highest. The average efficiency of the hydrogen fuel cell was increased by 2.87% and 1.2% respectively. Furthermore the equivalent hydrogen consumption of the tractor was reduced by 17.06% and 5.41% respectively within the experimental cycle. It is shown that the multi-layer control strategy considering power fluctuation can improve the vehicle economy based on meeting the power demanded by the whole vehicle load.

Currently most of the vehicles make use of fossil fuels for operations resulting in one of the largest sources of carbon dioxide emissions. The need to cut our dependency on these fossil fuels has led to an increased use of renewable energy sources (RESs) for mobility purposes. A technical and economic analysis of a one-stop charging station for battery electric vehicles (BEV) and fuel cell electric vehicles (FCEV) is investigated in this paper. The hybrid optimization model for electric renewables (HOMER) software and the heavy-duty refueling station analysis model (HDRSAM) are used to conduct the case study for a one-stop charging station at Technical University of Denmark (DTU)-Risø campus. Using HOMER a total of 42 charging station scenarios are analyzed by considering two systems (a grid-connected system and an off-grid connected system). For each system three different charging station designs (design A-hydrogen load; design B-an electrical load and design C-an integrated system consisting of both hydrogen and electrical load) are set up for analysis. Furthermore seven potential wind turbines with different capacity are selected from HOMER database for each system. Using HDRSAM a total 18 scenarios are analyzed with variation in hydrogen delivery option production volume hydrogen dispensing option and hydrogen dispensing option. The optimal solution from HOMER for a lifespan of twenty-five years is integrated into design C with the grid-connected system whose cost was $986065. For HDRSAM the optimal solution design consists of tube trailer as hydrogen delivery with cascade dispensing option at 350 bar together with high production volume and the cost of the system was $452148. The results from the two simulation tools are integrated and the overall cost of the one-stop charging station is achieved which was $2833465. The analysis demonstrated that the one-stop charging station with a grid connection is able to fulfil the charging demand cost-effectively and environmentally friendly for an integrated energy system with RESs in the investigated locations.

This work is aimed at solving the problem of converting diesel power drives to diesel– hydrogen fuels which are more environmentally friendly and less expensive alternatives to diesel fuel. The method of increasing the energy efficiency of diesel fuels has been improved. The thermochemical essence of using methanol as an alternative fuel to increase energy efficiency based on the provisions of thermotechnics is considered. Alternative methanol fuel has been chosen as the initial product for the hydrogen conversion process and its energy value cost and temperature conditions have been taken into account. Calculations showed that the caloric effect from the combustion of the converted mixture of hydrogen H2 and carbon monoxide CO exceeds the effect from the combustion of the same amount of methanol fuel. Engine power and fuel energy were increased due to the thermochemical regeneration of engine exhaust gas heat. An experimental setup was created to study the operation of a converted diesel engine on diesel–hydrogen products. Experimental studies of power and environmental parameters of a diesel engine converted for diesel–hydrogen products were performed. The studies showed that the conversion of diesel engines to operate using diesel– hydrogen products is technically feasible. A reduction in energy consumption was accompanied by an improvement in the environmental performance of the diesel–hydrogen engine working together with a chemical methanol conversion thermoreactor. The formation of carbon monoxide occurred in the range of 52–62%; nitrogen oxides in the exhaust gases decreased by 53–60% according to the crankshaft speed and loading on the experimental engine. In addition soot emissions were reduced by 17% for the engine fueled with the diesel–hydrogen fuel. The conversion of diesel engines for diesel–hydrogen products is very profitable because the price of methanol is on average 10–20% of the cost of petroleum fuel.

Hydrogen-yielding fermentation conducted in bioreactors is an alternative method of hydrogen production. However unfavourable processes can seriously inhibit bio-hydrogen generation during the acidogenic step of anaerobic digestion. Here ascomycetous yeasts were identified as a major factor inhibiting the production of bio-hydrogen by fermentation. Changes in the performance of hydrogen-producing bioreactors including metabolic shift quantitative changes in the fermentation products decreased pH instability of the microbial community and consequently a dramatic drop in bio-hydrogen yield were observed following yeast infection. Ascomycetous yeasts from the genera Candida Kazachstania and Geotrichum were isolated from hydrogen-producing bioreactors. Yeast metabolites secreted into the growth medium showed antibacterial activity. Our studies indicate that yeast infection of hydrogen-producing microbial communities is one of the serious obstacles to use dark fermentation as an alternative method of bio-hydrogen production. It also explains why studies on hydrogen fermentation are still limited to the laboratory or pilot-scale systems.

As an energy-intensive industry sector the glass industry is strongly affected by the increasingly stringent climate protection targets. As established combustion-based production systems ensure high process stability and glass quality an immediate switch to low greenhouse gas emission processes is difficult. To approach these challenges this work investigates a step-by-step integration of a Power-to-Hydrogen concept into established oxyfuel glass melting processes using a simulation approach. This is complemented by a case study for economic analysis on a selected German glass industry site by simulating the power production of a nearby renewable energy park and subsequent optimization of the power-to-hydrogen plant performance and capacities. The results of this study indicate that the proposed system can reduce specific carbon dioxide emissions by up to 60 % while increasing specific energy demand by a maximum of 25 %. Investigations of the impact of altered combustion and furnace properties like adiabatic flame temperature (+25 °C) temperature efficiency (∆ξ = −0.003) and heat capacity flow ratio (∆zHL = −0.009) indicate that pure hydrogen-oxygen combustion has less impact on melting properties than assumed so far. Within the case study high CO2 abatement costs of 295 €/t CO2-eq. were determined.. This is mainly due to the insufficient performance of renewable energy sources. The correlations between process scaling and economic parameters presented in this study show promising potential for further economic optimization of the proposed energy system in the future.

This study aims to present a philosophical and quantitative perspective of a propulsion system for a large-scale hydrogen-fuelled liquid-hydrogen (LH2) tanker ship. Established methods are used to evaluate the design and performance of an LH2-carrier propulsion system for JAMILA a ship designed with four cylindrical LH2 tanks bearing a total capacity of ~280000 m3 along with cargo and using the boil-off as propulsion and power fuel. Additionally the ship propulsion system is evaluated based on the ship resistance requirements and a hydrogen-fuelled combined-cycle gas turbine is modelled to achieve the dual objectives of high efficiency and zero-carbon footprint. The required inputs primarily involve the off-design and degraded performance of the gas-turbine topping cycle and the proposed power plant operates with a total output power of 50 M.W. The results reveal that the output power allows ship operation at a great speed even with a degraded engine and adverse ambient conditions.

This study investigated a pre-cooled turbojet engine for a Mach 5 class hypersonic transport aircraft. The engine was demonstrated under takeoff and Mach 2 flight conditions and a Mach 5 propulsion wind tunnel test is planned. The engine is composed of a pre-cooler a core engine and an afterburner. The engine was tested under simulated Mach 4 conditions using an air supply facility. High-temperature air under high pressure was supplied to the engine components through an airflow control valve and an orifice flow meter and liquid hydrogen was supplied to the pre-cooler and the core engine. The results confirmed that the starting sequence of the engine components was effective under simulated Mach 4 conditions using liquid hydrogen fuel. The pre-cooling effect caused no damage to the rotating parts of the core engine in the experiment.

The bipolar plate (BPP) is a component with vast cost-reduction potential in proton exchange membrane fuel cells (PEMFCs). Apart from mechanical and heat transfer requirements the most desired BPP properties are high corrosion and low electrical contact resistance. In this study we confirm that due to ionic decoupling between BPPs and electrodes the surface potentials of the BPPs remain stable even at varying operation loads. These mild potentials in combination with low metal-ion leeching due to passive-transpassive-passive dissolution in stainless steels suggest that low-cost carbon-coated stainless steel can readily be used as a BPP in PEMFCs. To prove this single-fuel cell tests were carried out under realistic driving conditions including electrochemical analysis in-situ contact-resistance measurements and post-mortem investigation of the membrane electrode assembly (MEA) by inductively coupled plasma trace-metal analysis combined with electron microscopy and Auger spectroscopy of the BPPs. The results show that due to the ionic decoupling conditions at the BPP surfaces are much less corrosive than previously thought. Furthermore carbon-coated stainless-steel BPPs prove to be unaffected by global hydrogen starvation which causes severe MEA degradation independent of the presence or absence of BPPs.

Since the beginning of the twenty-first century the limitations of the fossil age with regard to the continuing growth of energy demand the peaking mining rate of oil the growing impact of CO₂ emissions on the environment and the dependency of the economy in the industrialized world on the availability of fossil fuels became very obvious. A major change in the energy economy from fossil energy carriers to renewable energy fluxes is necessary. The main challenge is to efficiently convert renewable energy into electricity and the storage of electricity or the production of a synthetic fuel. Hydrogen is produced from water by electricity through an electrolyser. The storage of hydrogen in its molecular or atomic form is a materials challenge. Some hydrides are known to exhibit a hydrogen density comparable to oil; however these hydrides require a sophisticated storage system. The system energy density is significantly smaller than the energy density of fossil fuels. An interesting alternative to the direct storage of hydrogen are synthetic hydrocarbons produced from hydrogen and CO₂ extracted from the atmosphere. They are CO₂ neutral and stored like fossil fuels. Conventional combustion engines and turbines can be used in order to convert the stored energy into work and heat.

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