Volume 4 fuel cells and hydrogen technology 4 14 – future perspective on hydrogen and fuel cells

Volume 4 fuel cells and hydrogen technology 4 14 – future perspective on hydrogen and fuel cells Volume 4 fuel cells and hydrogen technology 4 14 – future perspective on hydrogen and fuel cells Volume 4 fuel cells and hydrogen technology 4 14 – future perspective on hydrogen and fuel cells Volume 4 fuel cells and hydrogen technology 4 14 – future perspective on hydrogen and fuel cells Volume 4 fuel cells and hydrogen technology 4 14 – future perspective on hydrogen and fuel cells

4.14 Future Perspective on Hydrogen and Fuel Cells K Hall, Technology Transition Corporation, Ltd., Tyne and Wear, UK © 2012 Elsevier Ltd All rights reserved 4.14.1 4.14.2 4.14.3 4.14.4 4.14.5 4.14.5.1 4.14.6 4.14.7 References Further Reading Overview Why Hydrogen? Hydrogen for Transport Stationary Power The Efficiency Debate A Holistic Approach From Here to There Conclusions Glossary Demand-side management (DSM) Modification of consumer demand for energy through education or financial incentives Holistic Relating to or concerned with wholes or with complete systems rather than with the analysis of, treatment of, or dissection into parts [1] 351 352 353 354 355 355 357 359 359 360 Integrated gasification combined cycle (IGCC) Technology that turns coal into a synthesis gas and involves generating electricity from gas turbines as well as steam-powered turbines 4.14.1 Overview Population growth is projected to continue in the foreseeable future (Excerpted from data from US Census Bureau 2009, Population Reference Bureau, and UN Department of Economic and Social Affairs as follows: [2–11]) More and more people are living in metropolitan areas Roads are becoming more congested [12], with incentives for mass transit and tariffs for driving personal automobiles in crowded cities becoming more commonplace As ultralow emission vehicles, such as hybrid electric vehicles, not contribute to the growing production of carbon emissions from vehicles, these are often exempted from congestion charging and are therefore highly sought after vehicles in areas such as London, where congestion-charging policies are in place The future presents an image of vehicles that rely less on a diminishing supply of fossil fuels and more on clean energy choices – such as a cleaner energy mix for electricity, clean efficient hydrogen fuel cells, and even hydrogen internal combustion engines Added to a growing mix of taxis and buses running on cleaner energy technologies [13–16] the near- to mid-term future looks much like the present day, only with cleaner air and fewer harmful emissions from transportation applications (Table 1) Hydrogen energy can contribute significantly to the future energy mix due to its versatility Not only can hydrogen be produced from fossil fuel feedstocks, it can also be produced from renewable energy resources and nuclear power The production of hydrogen in any of these ways provides many benefits, including the ability to store intermittent energy (e.g., from wind or PV) for use when demand outstrips supply, or in another application (such as transport) or another location This solution affords greater options for producing energy using renewable resources and providing this energy in many usable forms in the growing cities, providing clean stationary power as well as transport fuel Producing hydrogen from fossil fuels makes sense when and where the fossil fuels are abundant, providing energy to the end user without the carbon Large-scale power plants, therefore, could sequester the carbon, and provide power as electricity, gaseous hydrogen, or even liquid hydrogen if desired The ability of large-scale power plants to provide energy in these three forms opens new markets and delivers clean, reliable power It is important to understand that hydrogen energy will be used alongside many other forms of energy and enhance the overall efficiency of delivering clean fuel for a variety of applications How hydrogen will be used in the future depends on the specific needs of the community This chapter will describe many anticipated needs and how hydrogen can play a role in addressing those needs Today, there are many pre-commercial and early market applications of technologies that are critical on the path to a future energy mix that not rely on imported fossil fuels, and which contribute to carbon-reduction targets and allow communities to make the most of the energy resources available to them We will explore a number of these technologies and discuss their roles in the transition to a low-carbon energy future where hydrogen energy plays a dominant role alongside clean electricity And finally, the chapter will describe the future applications of hydrogen energy with respect to the projected energy supply needs Comprehensive Renewable Energy, Volume doi:10.1016/B978-0-08-087872-0.00403-0 351 352 Future Perspective on Hydrogen and Fuel Cells Table Projected increases in world population United States Census Bureau (2009) a 2010 2020 2030 2040 2050 830 586 985 557 514 266 202 205 367 748 743 446 202 458 484 Population Reference Bureau (1973–2008) b UN Department of Economic and Social Affairs (2008) c 352 000 000 908 688 000 674 833 000 308 895 000 801 196 000 149 984 000 4.14.2 Why Hydrogen? Let us begin by discussing the reasons why hydrogen is of interest There are many, and in reviewing the key policy drivers for hydrogen energy in a number of countries, The author has selected the predominant drivers that tend to appear in National policy documents more often than not: Security of Energy Supply, Greenhouse Gases/Climate Change, and Air Pollution/Environmental (United Kingdom Hydrogen Association [17], U.S Department of Energy [18], Canadian Hydrogen Association [19], European Comission [20], Ministry of New and Renewable Energy, India [21]) By their nature, fossil fuels are used faster than they are produced Although there continue to be significant resources discovered, the cost of accessing these resources has to be balanced against the cost of obtaining energy from other resources The issue is not one of scarcity of supply of fossil fuels; it is more about the difficulties of increasing that capacity to keep pace with increasing demand [22] In addition, carbon-based fuels contribute greenhouse gases to the atmosphere To ensure future supplies of fuel, and mitigate potential damage to the environment from combustion of fossil fuels, there is a trend toward sustainable supplies of energy The World Commission on Environment and Development defined sustainable development as development that “meets the needs of the present without compromising the ability of future generations to meet their own needs” [23] In practical terms, resources that are used more quickly than they can be renewed and create environmental damage cannot meet the requirement Therefore, although it is quite reasonable to expect that fossil fuels will continue to be a key part of our future energy mix, it is also reasonable to expect a growing portion of this energy mix to come from low-carbon and diverse supplies, with a growing emphasis on sustainability It is worth noting that indigenous, low-carbon energy supplies tend to be less dispatchable, or less capable of following demand variations, than conventional technologies Notable exceptions include large-scale hydroelectric and coal with precombustion carbon capture and storage (CCS) [2] (Figure 1) Therefore, a key risk associated with a decarbonized grid is supply variability resulting from the relatively poor dispatchability of many low-carbon generators This could result in increased difficulty in maintaining grid stability as low-carbon options are taken up Demand-side management (DSM) solutions are needed to ensure the necessary grid balancing There are many DSM solutions available, distinguished mainly by the storage timescales they provide Batteries, flow cells, flywheels, and supercapacitors are examples of short time-scale energy storage (less than a second to a few hours) Electricity storage and pumped hydroelectric are examples of medium time-scale energy storage (hours to a few days) It is important to recognize that the intermittent nature of many renewable energy technologies necessitates longer-term energy storage (can be weeks or more) Hydrogen has a unique role to play in meeting these longer-term needs Hydrogen, like electricity, is an energy carrier, rather than an energy source So, we are concerned with production, storage, and use, as in the case of electricity Assuming that the end products meet standard quality requirements, neither electricity nor hydrogen retains any ‘memory’ of the feedstocks or methods used to produce it Both are flexible that they can be produced from a variety of feedstocks, providing energy in a usable form where and when it is needed The societal movement to low-carbon options for energy generation is compatible with both electricity and hydrogen; however with this shift comes new issues which must be addressed As renewable energy increases penetration in the energy supply, the need for longer-term storage becomes greater [24] Generators such as conventional coal power plants, flexible combined cycle gas turbines, and open cycle gas turbine power plants are low load-factor generators with a relatively low capital expenditure required Adding postcombustion CCS increases both the load factor and capital expenditure One way this could be offset is to consider precombustion CCS with open cycle gas turbine power plants Precombustion CCS technologies are being developed One leading method currently being developed is a system called integrated gasification combined cycle (IGCC), which involves generating electricity from gas turbines as well as steam-powered ones [25] This approach enables the sale of hydrogen for industrial uses as well as a transport fuel As the energy supply becomes decarbonized and gas becomes more expensive, hydrogen from coal plus CCS or from electrolysis becomes a viable option; and in fact becomes a very attractive option [26] The point at which decarbonized hydrogen is competitive with conventional fossil fuel technologies depends on several factors – including the price of carbon and the price of the fossil fuels For example, when the CO2 value offsets the fuel conversion costs for a given application, the use of CCS and hydrogen as an intermediary energy vector becomes competitive with natural gas for energy generation Future Perspective on Hydrogen and Fuel Cells 353 Changing energy markets Energy security & climate change lead to Drive towards indigenous, low-carbon and diverse supplies Legend Hydro Allows supply-side management High These tend to be less ‘dispatchable’ (i.e., less capable of following demand variations) Open cycle gas turbine (OCGT) Geological, constrained resource Geological, abundant resource Coal with pre­ combustion CCS Renewable, constrained resource Medium Combined cycle gas turbine (CCGT) Carbon intensity Bio-energy (biomass, biogas & biofuels) Conventional coal High Coal with oxy-fueling or post-combustion CCS Requires demand-side management Low Dispatchability Renewable, abundant resource Low CHP Heat pumps Nuclear fusion Tidal Nuclear fission Solar (PV & thermal) Wave Wind Low Medium High Sustainability (Energy security + Low carbon intensity) Figure Dispatchability versus sustainability Reproduced with permission from Gammon R (2010) Dispatchability versus Sustainability Loughborough Leicestershire, UK: Bryte-Energy Limited [2] 4.14.3 Hydrogen for Transport There are currently many regions demonstrating hydrogen vehicles and refueling technologies In September 2009, nine major automotive manufacturers signed a letter of understanding to develop and launch fuel cell electric vehicles, with commercialization anticipated in the 2015 timeframe [27] Development of a hydrogen infrastructure for vehicles is well underway, with hydrogen stations across the world [28] The author has personally visited operating stations in California, Washington DC, Japan, Korea, the United Kingdom, and Germany The high energy density of hydrogen and rapid refueling times for hydrogen vehicles provide a distinct advantage to public charge points for electric vehicles In addition, home hydrogen refuelers are being developed which overcome the early difficulties of deploying widescale infrastructure in advance of mass commercialization of vehicles [29] (Figure 2) Research and development of hydrogen infrastructure is being conducted worldwide The economics depend on a number of factors including geographical location, hydrogen production techniques, storage technology and timeframe, and distribution methods Most cost-effective production techniques may vary as each region considers the resources available to them Japan is intensely investigating options to provide sustainable stationary and transportation power to large cities and has identified utilization rate as the key factor in making a hydrogen infrastructure economical [30] Electrification of vehicle power trains is required to decarbonize transport Batteries and hydrogen are two ways of achieving this and all leading OEMs that have active programs in both areas It is worth noting that commercial fuel cell vehicles under development are hybrids, combining batteries, and fuel cells The hybrid electric vehicle operates the fuel cell as an alternative power unit to supply the power required by the vehicle, to recharge the batteries, and to power accessories such as the air conditioner and heater According to a US training module developed by the College of the Desert, Hybrid electric cars can exceed the limited 100 mile (160 km) range-per-charge of most electric vehicles and have the potential to limit emissions to near zero A hybrid can achieve the cruising range and performance advantages of conventional vehicles with the low-noise, low-exhaust emissions, and energy independence benefits of electric vehicles [31] 354 Future Perspective on Hydrogen and Fuel Cells Hydrogen fuel cell vehicles introduction scenario The densitiy of vehicles in the area Initial market for fuel cell vehicles (Areas) (Fleet vehicles in mega cities) Passenger cars in of mega cities (Yokohama, Kawasaki/Nagoya, Osaka) Passenger cars in the central of Tokyo Fleet vehicles in the central of Tokyo (Passenger car and light duty van) T a r g e t (Passenger vechicles in mega cities) Passenger cars in of mega cities (Yokohama, Kawasaki/Nagoya, Osaka) Passenger cars in central Tokyo 2500 vehicles/km2 2000−3500 vehicles/km2 100−400 vehicles/km2 2500 vehicles/km2 2000−2500 vehicles/km2 (Passenger vehicles in suburb of mega cities) Passenger cars in suburb of mega citites Vehicles Number 1,000 vehicles per year 1,000 vehicles per year 500 vehicles/km2 Time Figure Honda solar hydrogen filling station in Torrence, California Reproduced with permission from ENEA (2010) Vision of a Hydrogen/Electric Energy Scenario Rome, Italy: ENEA 4.14.4 Stationary Power Fuel cells that operate on hydrogen energy are available on the market today They come in a variety of sizes for a variety of applications The solution is carefully matched with the problem that needs to be solved There is much more information on the variety of fuel cell technologies available today elsewhere in this volume They are mentioned here only to provide a brief context for a transition from the energy mix of today, to the energy mix of the future, where hydrogen plays a more dominant role It is anticipated the market penetration for stationary fuel cells will continue to grow, as hydrogen becomes more widely available Future Perspective on Hydrogen and Fuel Cells 355 4.14.5 The Efficiency Debate Efficiency is a key issue that is often raised by those who believe hydrogen energy has no future Some ask why we would convert electricity to hydrogen, and then back to electricity To answer this question, keep in mind that efficiency must not be considered in isolation of the needs of society In addition, consideration must be given to efficiency gains of capturing energy that would otherwise be lost in order to gain a more complete picture How, for example, does one measure the efficiency of a system that allows you to capture renewable energy that otherwise would have not been captured? Rather than turning some wind turbines off at night when supply outstrips demand, the turbines can be allowed to operate fully, thereby increasing the utilization rate of the wind energy system Wind power that cannot be used for stationary power or exported to the grid could be used in power electrolyzers to produce hydrogen This hydrogen could then be used in stationary or transport applications where and when needed Thus, although there will undoubtedly be efficiency losses in each step of transfer or conversion, you are starting with a resource that was not going to be used at all Therefore, even if you achieve a system efficiency of 45%, for example, does it make sense to imply you are somehow ‘losing’ 55% of the energy when your starting position was to lose 100% by switching off the wind turbines? Even so, if we want to simply look at the efficiency of the stack and the electrolyzer system, recent progress reports show electrolyzer stack efficiencies between the low seventies and the upper eighties, depending on the specific components and materials used System efficiencies, however, vary with the power of the system Let us take sample data from recent research at NREL [32] Looking at a 6.5 kW system at 135 A, a measured hydrogen flow of 1.05 Nm3 h−1, the reported High Heat Value system efficiency is 57.4 and the low heat value system efficiency is 48.5% 4.14.5.1 A Holistic Approach Hydrogen is meant to be considered holistically – throughout the energy chain It complements electricity, allowing for useful energy to be available in an appropriate form where and when it is needed Both electricity and hydrogen will continue to be important throughout the heat, electricity, and transport sectors; and both will continue to be produced in more sustainable, environmentally friendly ways There have been many critics of hydrogen energy who point to narrow applications and show, correctly, that hydrogen may be less efficient or more expensive than other technologies [33] However, these critics fail to look at hydrogen’s role across the energy spectrum, and therefore give any credit for hydrogen serving multiple needs simultaneously The following figure from AMEC depicts the potential complex role of hydrogen for providing the capacity, the flexibility, and the sustainability of a future energy system across heat, electricity, and transport sectors (Figure 3): GHG impact Solids, Coal Fossil Post & Oxy combustion Needs CCS Primary resource Distributed heat Poor Electricity applications Responsive Demand management Plant turndwown Carbon or syn gas H2 pipe or store Fischer­ Tropsch Pre combustion Post & Oxy combustion Gas Poor, unless no CCS Additional process Transport Liquid fuelICE Liquid fuelAviation Good response Other chemicals & products Pre combustion H2 ICE Oil Biomass 1st generation impacting land use 2nd generation careful land use Not sustainable Good Good response H2 pipe or store H2 Fuel cell Not sustainable Additional benefits with CCS Good only if small scale Responsive Renewables Good Poor Base loads Nuclear (#) Good Poor Good Smart electrolysis Residual needs use fossil fuels Time shift loads (# Higher temperature reactors will be able to directly produce hydrogen-this benefit is not shown here) Electrical storage Batteries AMEC October 2010 Figure A holistic approach for hydrogen Reproduced with permission from ITM Power (2010) Hydrogen Powered Home Sheffield, UK: ITM Power 356 Future Perspective on Hydrogen and Fuel Cells NREL [34] has shown That hydrogen can be produced at the wind site for prices ranging from $5.55 per kg in the near term to $2.27 per kg in the long term A research opportunity in this scenario is the elimination of redundant controls and power electronics in a combined turbine/electrolysis system Hydrogen fuel cells can be used as a buffer for intermittent renewable resources There are examples of systems that use solar or wind turbines, coupled with electrolysis for hydrogen production Renewable energy resources are not distributed equally throughout the world, and require significant areas to deploy technologies to gather sizeable amounts of energy In order for these types of energy resources to become more practical, the energy needs to be easy to store, transport, and use Coupling renewable resources with hydrogen not only achieves this, but it also allows this stored energy to be used as a sustainable transport fuel [35] One such project is the Wind2H2 project in the United States, which links wind turbines and photovoltaics to electrolyzers, which pass the renewably generated electricity through water to split it into hydrogen and oxygen The hydrogen can then be stored and used later to generate electricity from an internal combustion engine or a fuel cell (Figure 4) The Wind2H2 project seeks to improve the system efficiency of producing hydrogen from renewable resources in quantities large enough and at costs low enough to compete with traditional energy sources such as coal, oil, and natural gas Some success has already been achieved in optimizing power electronics [36] Renewable electricity, particularly which is above and beyond the demand for the direct electricity at the time and therefore would not be captured, can be converted via electrolysis to produce hydrogen This hydrogen can then be used to power the fuel cell during peak demand Critics will point to the fact that it is more efficient to use the renewable electricity directly – which is true when that is an option However, the nature of intermittent resources and transmission lines means that there will be times when the system is capable of generating more electricity than is needed Often, this results in some wind turbines being switched off, for example The electricity which could be generated by these turbines could be used to electrolyze water to store hydrogen for those times when demand is greater than can be supplied directly from the renewable resources In a case like this, how does one characterize the efficiency? The system is using energy which otherwise would not have been captured at all The turbines are already in place The efficiency debate applies to all areas of hydrogen production, storage, and use The same debate can be made of electricity, but rarely is made, because we not wish to burn coal in our homes to heat water or power our television or computers Both hydrogen and electricity are used in a form which is clean and quiet easy to use where and when it is needed Electricity provides electrons, and hydrogen can provide electrons with gaseous or liquid storage Yes, it takes energy to provide any of these As society moves to more environmentally sustainable energy resources, the game becomes one of capturing more of this energy, not only how efficiently we use but also what has been captured Consider the case of renewable resources where 50% of the available energy is captured, and that is used 80% efficiently versus adding hydrogen storage to capture 80% of the available energy which may be used 50% efficiently The current efficiency debate focuses only on the efficiency of use after conversion losses; however these two scenarios actually are comparable Now when 95% 10 kW Photovoltaics Excess gridcompatible electricity Bergey 10 kW Wind turbine AC–DC Converter ASCO transfer switch NPS 100 kW Power wind turbine converter DC–DC Converter Utility grid AC power Proton energy Proton energy HOGEN 40RE (PEM) HOGEN 40RE (PEM) Teledyne HM-100 (Alkaline) Hydrogen engine center 60 kW genset Hydrogen Output H2 filling station Hydrogen compression and strorage 3,500 PSI 115 kg hydrogen storage capacity Figure Overall Wind2H2 system diagram Future Perspective on Hydrogen and Fuel Cells 357 of the available energy is captured and used 60% efficiently, more overall energy is available for use So in this case, the efficiency debate needs to include the ability to capture the resource in the first place as well as the conversion losses prior to use Recall the need for long-term storage of intermittent renewable energy discussed previously The addition of electrolysis and hydrogen storage means that the renewable resource need not be turned off overnight or during other times of low demand Capturing and storing some of this energy for use when demand outstrips supply increases the energy output from the renewable energy system, helps manage supply and demand issues, and creates a store of energy which can be used in a number of applications, including fueling hydrogen vehicles Farms that operate wind turbines may use the excess hydrogen to power farm equipment, becoming more self-sustaining; or the excess hydrogen can be sold as a commodity In fact, hydrogen opens new markets for electricity to include fuel for vehicles Critics will point out that electricity can be used directly as a vehicle fuel in battery electric vehicles (BEVs) Yes, of course, this is true The difficulty has been in ensuring the capacity required to provide the electricity to the vehicle while maintaining capacity for other uses In the case of hydrogen, which can be delivered as a gas or liquid as well as electrons, there are simply more options When and where it is not convenient to deliver electrons to the vehicle, hydrogen can be delivered as a gas or liquid, reducing refueling/recharging times and avoiding an additional demand on the electrical grid In areas where there is no electrical grid or no additional capacity, this is especially attractive One reason someone may want to suffer the efficiency losses in converting electricity to hydrogen, and then back to electricity, may relate to intermittency of renewable energy During the times when a photovoltaic system or wind turbine is capable of producing more electricity than the user can use at the time, the surplus renewable power could be used to make surplus electricity If there is a need to store this electricity, one option for this is through hydrogen production by electrolysis Although there are efficiency losses in this conversion, we are starting with energy that was not usable Any energy captured in this way is basically bonus energy that would have been lost otherwise What is then done with this energy is a matter of individual needs and circumstances Someone may choose to store the hydrogen, and then run the hydrogen through a fuel cell to create electricity locally when the demand for the renewable electricity exceeds the supply In this way, more of the renewable energy is captured than can be used directly, and this helps resolve the intermittency issues with renewable energy Hydrogen is used as an energy storage mechanism for renewable resource Perhaps there is not a need to capture the energy for local use Or perhaps the renewable energy system is capable of providing more electricity than can be used locally, even accounting for intermittency issues In this case, the excess energy could still be converted to hydrogen, but now the hydrogen could be sold as a commodity, or used to power vehicles The ability to gain revenue from this energy as a vehicle fuel may be an attractive option The author believes the key to the future of hydrogen energy lies in its flexibility No single production method is expected to dominate the future of hydrogen production Precombustion CCS, electrolysis, nuclear, bio-energy, and others all will likely have a role to play The flexibility in production methods provides greater flexibility in solving a broader array of energy issues than a single production method would It is worthwhile to consider the broader energy picture to better understand why energy conversion is not the barrier that it may seem to be at first glance Figure depicts a vision of a future hydrogen/electric energy scenario It shows the flexibility in generation described in this chapter, and how the hydrogen, regardless of how it is produced, can be delivered as electricity, gas, or liquid for a variety of applications In this hydrogen vision, hydrogen is produced from all available feedstocks, including fossil fuel power plants that utilize Carbon-Capture technologies The hydrogen that is delivered to the filling station has no memory – it may have come from any of the available feedstocks Yet, it is delivered to the grid, fuel cell, or vehicle in a standardized form, ensuring a consistent, robust hydrogen infrastructure throughout the world The concept of sustainable energy with hydrogen as a key component is one that is embraced all over the world [38] Even in countries where hydrogen demonstrations are not yet as prevalent as they are in North America, Germany, and Japan, we are seeing promising advanced research results Scientists at Korea’s S&P Energy Research Institute, for example, are working on chemical processes for manufacturing hydrogen that can reduce the cost of producing hydrogen by 20–30 times [39] And in the last years, India formed a hydrogen association [40] and installed its first hydrogen fuel-dispensing bunk [41] In addition, the first hydrogen highway opened in Norway in 2009 [42] 4.14.6 From Here to There To appreciate the potential of hydrogen energy, it is important to understand from the beginning The starting point for a transition that includes abundant clean hydrogen is where we are today Presently, there is a robust electricity network and fossil fuel infrastructure Electricity is made predominantly from coal and nuclear feedstocks, with a growing portion coming from a variety of renewable energy technologies Supporters for hydrogen energy point out that as power production in general moves away from fossil fuels, the amount of hydrogen produced from clean resources will also grow Renewable resources will become the dominating energy source and renewable electricity will require new energy storage capacities [43] In this way, the carbon footprint of hydrogen tracks the carbon footprint of electricity Figure shows a home scenario where the homeowner is using renewable energy for electricity and generating hydrogen gas for home appliances as well as the family car 358 Future Perspective on Hydrogen and Fuel Cells Hydropower Thermal solar Wind turbine Biomass PV plant H2 Power generation Plant H2 production plant H2 CO2 Fuel cell plant Filling station Natural gas Depleted gas well Deep saline acquifer HYDROGEN VISION Figure Vision of a hydrogen/electric energy scenario, used with permission from ENEA Reproduced with permission from ENEA (2010) Vision of a Hydrogen/Electric Energy Scenario Rome, Italy: ENEA [37] Figure Hydrogen powered home used with permission from ITM Power Reproduced with permission from ITM Power (2010) Hydrogen Powered Home Sheffield, UK: ITM Power [44] Future Perspective on Hydrogen and Fuel Cells 359 In this scenario, hydrogen again plays the role of energy buffer with intermittent renewable resources In addition, it allows for a separate stream of gaseous energy, suitable for home appliances and vehicles 4.14.7 Conclusions Hydrogen will have an important role to play in decarbonized transport and electricity generation, as part of a mix that includes a range of other technologies (e.g., biofuel, BEVs, renewable resources, nuclear, and fossil fuel with CCS) (Orion Innovations [45]) A major decarbonization problem will be heat, in particular season peak loads Such loads may benefit from hydrogen, which is commercially more attractive over longer-term storage The use of hydrogen energy offers benefits (United Kingdom Hydrogen Association [17]) at the large scale, such as hydrogen from precombustion CCS, off-peak and grid balancing of national grid electricity, storage and supply of low-carbon energy for heat, and particularly transport applications, as well as at the small scale, such as community and distributed systems utilizing wind, tidal, wave, photovoltaic, and other renewable resources with hydrogen fuel cell systems, standby and mobile, and auxiliary power, just to name a few Hydrogen can contribute by acting as an energy store to balance supply and demand, in a similar manner to batteries with electricity but at a lower storage cost; and providing an energy storage medium or a transport fuel as a sidestream from precombustion CCS power stations Hydrogen is available today from refinery gasifiers with a wide range of inputs, natural gas, biogas or waste, and electrolysis of water at overall efficiencies ranging from 50% to 70% The hydrogen can already be made in large centralized plants or in smaller distributed units located close to refueling requirements Construction of a hydrogen infrastructure will follow demand, under normal commercial terms However, like recharging points, the first refueling stations need deployment support Improvements in utilization of renewable resources and hydrogen, as well as in system efficiencies will make these technologies commercially attractive over a wider range of applications Electrolytic hydrogen is an embedded solution and 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Power [45 ] Orion Innovations (2009) Hydrogen Future Study – HyFuture Glasgow, UK: The Scottish Hydrogen and Fuel Cell Association Further Reading [1] Fuel Cell and Hydrogen Energy Association Renewable... approach for hydrogen Reproduced with permission from ITM Power (2010) Hydrogen Powered Home Sheffield, UK: ITM Power 356 Future Perspective on Hydrogen and Fuel Cells NREL [ 34] has shown That hydrogen