Quantitative analysis of a successful public hydrogen station

Reliable hydrogen fueling stations will be required for the successful commercialization of fuel cell vehicles. An evolving hydrogen fueling station has been in operation in Irvine, California since 2003, with nearly five years of operation in its current form. The usage of the station has increased from just 1000 kg dispensed in 2007 to over 8000 kg dispensed in 2011 due to greater numbers of fuel cell vehicles in the area. The station regularly operates beyond its design capacity of 25 kg/day and enables fuel cell vehicles to exceed future carbon reduction goals today. Current limitations include a cost of hydrogen of $15 per kg, net electrical consumption of 5 kWh per kg dispensed, and a need for faster back-to-back vehicle refueling.     

Risk-constrained design of autonomous hybrid refueling station for hydrogen and electric vehicles using information gap decision theory

The proposed autonomous hybrid charging station in this paper is energized by a photovoltaic (PV) system, which should provide electric vehicles (EVs), and water electrolyzer (WE) with electricity. The WE operates by using electricity to produce and store hydrogen to feed hydrogen vehicles (HVs). Moreover, a fuel cell (FC) is allocated to the system, which uses the stored hydrogen to regenerate electricity the PV system is beyond reach. A supplementary diesel generator is also installed in the charging station to avoid power shortage as a conservative measurement. The hydrogen and electric demand of the station is accompanied by uncertainties, which should be taken into account in designing the charging station. Therefore, information-gap decision theory (IGDT) is employed to deal with the uncertainties. This approach provides the investor with three different strategies of risk-averse strategy (RAS), risk-neutral strategy (RNS), and risk-seeker strategy (RSS), which can help the investor with making a better decision. The outcome of the simulation proved that in RAS if the investor decides to invest 13.9% more capital, based on the robustness function, the charging station withstands the 9.6% deviation of uncertain parameters’ fraction error. However, should the investor decide to take risks in the construction of the charging station, by paying 13.9% less, the system is 10.7% fragile to the information-gap of uncertainties. Besides, the rated power of the PV system reaches from 1612 kW in RNS to 1731 kW in RAS while it decreased to 1479 kW in RSS.     

Modeling operating modes,energy consumptions,and infrastructure requirements of fuel cell plug in hybrid electric vehicles using longitudinal geographical transportation data

The fuel cell plug in hybrid electric vehicle (FCPHEV) is a near-term realizable concept to commercialize hydrogen fuel cell vehicles (FCV). Relative to conventional FCVs, FCPHEVs seek to achieve fuel economy benefits through the displacement of hydrogen energy with grid-sourced electrical energy, and they may have less dependence on a sparse hydrogen fueling infrastructure. Through the simulation of almost 690,000 FCPHEV trips using geographic information system (GIS) data surveyed from a fleet of private vehicles in the Puget Sound area of Washington State, USA, this study derives the electrical and hydrogen energy consumption of various design and control variants of FCPHEVs. Results demonstrate that FCPHEVs can realize hydrogen fuel consumption reductions relative to conventional FCV technologies, and that the fuel consumption reductions increase with increased charge depleting range. In addition, this study quantifies the degree to which FCPHEVs are less dependent on hydrogen fueling infrastructure, as FCPHEVs can refuel with hydrogen at a lower rate than FCVs. Reductions in hydrogen refueling infrastructure dependence vary with control strategies and vehicle charge depleting range, but reductions in fleet-level refueling events of 93% can be realized for FCPHEVs with 40 miles (60 km) of charge depleting range. These fueling events occur on or near the network of highways at approximately 4% of the rate (refuelings per year) of that for conventional FCVs. These results demonstrate that FCPHEVs are a type of FCV that can enable an effective and concentrated hydrogen refueling network.     

Comparative analysis of battery electric,hydrogen fuel cell and hybrid vehicles in a future sustainable road transport system

This paper compares battery electric vehicles (BEV) to hydrogen fuel cell electric vehicles (FCEV) and hydrogen fuel cell plug-in hybrid vehicles (FCHEV). Qualitative comparisons of technologies and infrastructural requirements, and quantitative comparisons of the lifecycle cost of the powertrain over 100,000 mile are undertaken, accounting for capital and fuel costs. A common vehicle platform is assumed. The 2030 scenario is discussed and compared to a conventional gasoline-fuelled internal combustion engine (ICE) powertrain. A comprehensive sensitivity analysis shows that in 2030 FCEVs could achieve lifecycle cost parity with conventional gasoline vehicles. However, both the BEV and FCHEV have significantly lower lifecycle costs. In the 2030 scenario, powertrain lifecycle costs of FCEVs range from $7360 to $22,580, whereas those for BEVs range from $6460 to $11,420 and FCHEVs, from $4310 to $12,540. All vehicle platforms exhibit significant cost sensitivity to powertrain capital cost. The BEV and FCHEV are relatively insensitive to electricity costs but the FCHEV and FCV are sensitive to hydrogen cost. The BEV and FCHEV are reasonably similar in lifecycle cost and one may offer an advantage over the other depending on driving patterns. A key conclusion is that the best path for future development of FCEVs is the FCHEV.     

Comments on solid state hydrogen storage systems design for fuel cell vehicles

In recent years, significant research and development efforts were spent on hydrogen storage technologies with the goal of realizing a breakthrough for fuel cell vehicle applications. This article scrutinizes design targets and material screening criteria for solid state hydrogen storage. Adopting an automotive engineering point of view, four important, but often neglected, issues are discussed: 1) volumetric storage capacity, 2) heat transfer for desorption, 3) recharging at low temperatures and 4) cold start of the vehicle. The article shall help to understand the requirements and support the research community when screening new materials.     

Techno-economic and behavioural analysis of battery electric,hydrogen fuel cell and hybrid vehicles in a future sustainable road transport system in the UK

This paper conducts a techno-economic study on hydrogen Fuel Cell Electric Vehicles (FCV), Battery Electric Vehicles (BEV) and hydrogen Fuel Cell plug-in Hybrid Electric Vehicles (FCHEV) in the UK using cost predictions for 2030. The study includes an analysis of data on distance currently travelled by private car users daily in the UK. Results show that there may be diminishing economic returns for Plug-in Hybrid Electric Vehicles (PHEV) with battery sizes above 20 kWh, and the optimum size for a PHEV battery is between 5 and 15 kWh. Differences in behaviour as a function of vehicle size are demonstrated, which decreases the percentage of miles that can be economically driven using electricity for a larger vehicle. Decreasing carbon dioxide emissions from electricity generation by 80% favours larger optimum battery sizes as long as carbon is priced, and will reduce emissions considerably. However, the model does not take into account reductions in carbon dioxide emissions from hydrogen generation, assuming hydrogen will still be produced from steam reforming methane in 2030.     

A fuel cell powered autonomous surface vehicle: The Eco-SWAMP project

Autonomous surface vehicles are becoming consolidated robotic tools for marine, coastal and inland surveys. Autonomous surface vehicles are usually equipped with electronic instruments to perform remotely controlled or autonomous geo-morphological, biological, chemical, physical analyses and data collection. Actually, well-established solutions provide battery power but the research focuses on introducing a fuel cell to decrease the environmental impact meanwhile increasing the cruising range. In this paper, the design of the Eco-SWAMP, a fuel cell powered autonomous surface vehicle, is presented starting from its battery-powered version, the SWAMP prototype. The experimental power consumption profile of the SWAMP during four missions is analysed to define the primary energy sources ratings of the Eco-SWAMP. After a commercial choice of primary sources, power management algorithms are designed and compared in MATLAB/Simulink environment by simulation results. The proposed procedure can be easily applied to any autonomous marine vehicle.     

Hydrogen release properties of lithium alanate for application to fuel cell propulsion systems

In this paper the results of an experimental study on LiAlH₄ (lithium alanate) as hydrogen source for fuel cell propulsion systems are reported. The compound examined in this work was selected as reference material for light metal hydrides, because of its high hydrogen content (10.5 wt.%) and interesting desorption kinetic properties at moderate temperatures. Thermal dynamic and kinetic of hydrogen release from this hydride were investigated using a fixed bed reactor to evaluate the effect of heating procedure, carrier gas flow rate and sample form. The aim of this study was to characterize the lithium alanate decomposition through the reaction steps leading to the formation of Li₃AlH₆ and LiH. A hydrogen tank was designed and realized to contain pellets of lithium alanate as feeding for a fuel cell propulsion system based on a 2-kW Polymeric Electrolyte Fuel Cell (PEFC) stack. The fuel cell system was integrated into the power train comprising DC-DC converter, energy storage systems and electric drive for moped applications (3 kW). The experiments on the power train were conducted on a test bench able to simulate the vehicle behaviour and road characteristics on specific driving cycles. In particular the efficiencies of individual components and overall power train were analyzed evidencing the energy requirements of the hydrogen storage material.     

Two-stage robust energy management of a hybrid charging station integrated with the photovoltaic system

The optimal management of charging stations has become a critical issue in recent years. In this paper, the energy management of a hybrid charging station composed of an electrolyzer, fuel cell and hydrogen storage is analyzed that is integrated with a photovoltaic system. As well, the station is connected to the local power market to increase flexibility and it is assumed that the manager of the charging station is an intelligent decision-maker who tries to minimize the cost of vehicle. Due to the existence of uncertainties, generation of photovoltaic, market price and load demand are considered as uncertain parameters and two-stage stochastic programming is applied to model them. To achieve optimal management, a robust optimization approach is proposed for the uncertainty of day-ahead market price where the decision-maker adjusts the conservatism level. The presented method is linear risk-constrained programming that the results for risk-neutral and risk-averse strategies are compared. To validate the accuracy and robustness of the approach, interval-based stochastic programming is also implemented. According to the robust optimization, day-ahead market price uncertainty increases the total expected cost by about 8.9%. In return, the risk of scheduling is reduced significantly with the risk-averse strategy.     

Fuel cells for road transportation purposes — yes or no?

The issues surrounding the application of fuel cells for road transportation are evaluated. The advantages and disadvantages of the candidate fuel-cell systems and the various fuels are discussed, together with the issue of whether the fuel should be converted directly in the fuel cell or should be first converted to hydrogen on-board the vehicle. Developments in competing vehicles technologies, namely, internal-combustion-engined vehicles (ICEVs), pure-battery vehicles (EVs) and ICE–battery hybrid vehicles (HEVs) are reviewed. Finally, the impact of the introduction of fuel-cell vehicles (FCVs) on industry, and in particular on the oil and automotive industries, is examined. For FCVs to compete successfully with conventional ICEVs, it is concluded that direct-conversion fuel cells — using probably hydrogen, but possibly methanol — are the only realistic contenders for road transportation applications.     

Simulation,economic and environmental evaluations of green solar parking (refueling station) for fuel cell vehicle

Energy storage is needed for renewable systems due to the intermittent nature of wind and solar energy. Hydrogen can be used to store variable renewable energy such as solar and wind energy. According to this fact, there is an increasing interest in use of solar-hydrogen systems for power supply in remote areas or other standalone applications. One of these applications is Hydrogen production station working by solar energy to use in fuel cell vehicle. Time consuming aspect of solar-hydrogen production is the most prominent reason for presenting a new scheme as a parking-refueling station for fuel cell vehicles in this study. To do this, Simulation, economic and environmental evaluations of the solar parking-refueling station are considered in this article. Because of using an independent hydrogen compression system, the suggested parking-refueling station can be used in a standalone area such as rural and military applications. Results show that the proposed system seems to be economic in present condition. It also illustrates that the Levelized Cost of Product (Km-Passenger) is in a range of 0.15–0.28 US$. Although using the tracker system is not economically efficient, the effect of such a structure is more obvious in the points far from tropical area.     

Cryosorption storage of gaseous hydrogen for vehicular application – a conceptual design

A conceptual design for the cryosorption storage of gaseous hydrogen in activated carbon for vehicular application has been presented. In this work, a novel concept for the storage/discharge of hydrogen has been proposed. This system ensures faster filling and gradual release of hydrogen on demand. These two features are important for making onboard hydrogen storage effective for small cars. Numerical models for adsorption and desorption half cycles are presented. Assuming that the pressurisation and depressurisation are occurring adiabatically, transient analysis has been done to critically study the effective hydrogen storage capacity of activated carbon. The amount of activated carbon required to store hydrogen for travelling a specific distance has been computed.     

Fuel cells and odorants for hydrogen

Odorants have been proposed as a reliable, inexpensive means to enable leak detection for hydrogen systems and increase public safety. However, traditional odorants cause problems for fuel cell systems. This paper examines the use of odorants for fuel cell systems, including the hydrogen storage. Current odorants and potential odorants have negative impacts on fuel cell performance. Odorants also appear to be problematic for most of the advanced hydrogen storage options. If odorants are used, the odorants will probably need to be removed from the hydrogen prior to the storage medium. Current hydrogen detectors are more reliable than the odorant–human detection system and should provide increased safety.     

Sustainable convergence of electricity and transport sectors in the context of a hydrogen economy

This paper analyzes the electricity and transport sectors within a single integrated framework and presents the capabilities of this integrated approach to realize an environmentally and economically sustainable transport sector based on fuel cell vehicles (FCVs). A comprehensive robust optimization planning model for the transition to FCVs is developed, considering the constraints of both electricity and transport sectors. This model is finally applied to the real case of Ontario, Canada to determine the Ontario’s grid potential to support these vehicles in the transport sector for a planning horizon ending in 2025. With a reasonable trade-off between optimality and conservatism, it is found that more than 170,000 FCVs can be introduced into Ontario’s transport sector by 2025 without jeopardizing the reliability of the system or any additional grid investments such as new power generation and transmission installations.