The Hydrogen Gas Market

Along with the economic, environmental, and energetic performance of the alternative technologies, there are sociological (e.g., behavioural) uncertainties about the widespread utilization of hydrogen-fuelled vehicles. An example of these uncertainties is the consumer acceptance of new technologies. For instance, when it comes to BEVs, there are a couple of important behavioural questions to ask, such as whether or not the vehicle owners would accept low-driving vehicles, how often vehicle owners would be willing to charge their vehicles, etc. Driving range is especially a critical issue when developing alternative transportation vehicles. With the current available technologies, ICE-powered vehicles offer durable, reliable, affordable, safe, and long-range driving to drivers that hydrogen-fuelled vehicles or BEVs cannot compete with. Another example of vehicle charging concerns is related to BEVs; in the long-term, it is expected that severe problems will surface related to BEV charging and its impacts on the local, national, and global electricity grid. The reason for these concerns is the fact that most owners are expected to charge their vehicles during peak consumption periods, which generally means after business hours, which end around 6 p.m. or so. In addition, currently, there are not many studies on potential BEV owners’ charging preferences and behaviours. The University of Birmingham Fuel Cell Group has conducted different simulations and modelling studies on BEV drivers in England and so far, they have concluded that the majority of owners and drivers prefer charging their vehicles during peak times in contrast with the recommended use during off-peak times . An additional and much more important element that affects the hydrogen energy market in the transportation sector is the GHG emissions reduction that could be achieved with hydrogen compared to other alternative fuel options with low emissions, such as biobased fuels. In the transportation sector, biobased fuels can potentially become the most cost-effective, clean, reliable, and efficient alternative to traditional fossil fuel-based transportation fuels, which poses a threat to hydrogen energy market expansion. The reason for the potential success of biobased fuels is their ease of production, delivery, and end use. In addition, biobased fuels may not necessitate a drastic infrastructure renovation. As mentioned earlier, biobased fuels have several advantages as transportation fuels. However, in spite of their substantial potentials, biobased fuel sources cause a lot of polemics. An important concern about biobased fuels is related to the conservation of agricultural lands. Unless biobased fuels are derived from industrial, agricultural, or municipal waste, there will always be a “food versus fuel” debate on biobased sources. In addition, in order to be considered as truly renewable, the biobased fuels should be replenished at a higher (or equal) rate compared to their rate of consumption. Furthermore, a thorough well-to-wheel analysis should be conducted to evaluate the net GHG emissions related to biobased fuel use. Over and above the issues highlighted here so far, there are some political aspects and policy-related issues that significantly affect the expansion of the hydrogen energy market, especially hydrogen in the transportation sector. There needs to be specific consumer-driven demand for the successful growth of the hydrogen energy market and extensive use of hydrogen as a transportation fuel. Until now, there has been no significant demand from key consumer groups on the use of hydrogen as a transportation fuel [65]. Transition to hydrogen use in the current transportation industry requires substantial policy changes. This is a unique situation because there have been no major energy system shifts in history with such policy change requirements. In the late 19th century, the main reason for the evolution from horse-driven transportation to ICE-driven vehicles was the demand coming from vehicle users to be able to travel longer distances [66]. Since there has been no major consumer demand for hydrogen-powered vehicles, the responsibility for a successful transition to a hydrogen economy is on local and state-level governments, representatives from various industries and institutions, and hydrogen energy system supporters to accelerate the transition to a fully developed hydrogen energy market by leading:

• Behavioural transition: for hydrogen to be accepted by all end users.
• Technological demonstrations: to prove that the hydrogen energy market is ready.
• Competitive assessments: demonstrate the advantages of hydrogen compared to other existing alternatives.

There have been many obstacles considered during the transition to a successfully developed hydrogen energy market. Even if all these challenges related to hydrogen use as a transportation fuel are addressed, there will be additional requirements for an effective market introduction, such as investments in refueling infrastructure and novel vehicle technologies, incentives to purchase hydrogen-fueled vehicles to keep them as affordable alternatives for consumers before mass production begins, etc. [67]. In order to achieve a successful transition to hydrogen as a transport fuel, governments have to play a prominent role by maintaining and augmenting incentives that can promote the uptake and mass market appeal of the next generation of zero-emission vehicles in an effort to decarbonize the road transport system.   There are many novel hydrogen energy markets from stationary to portable applications, and in small and large scale. Some examples of these markets are midscale stationary fuel cell-powered energy systems with capacities from 200 to 1000 kW. Hydrogen-powered CHP and combined cooling, heat, and power (CCHP) facilities can be utilized for district power generation and heating purposes. Hydrogen energy systems can also potentially be used for off-grid power generation in micro- and ultimately macroscales. The Energy Savings Trust has proposed that microgeneration products (e.g., fuel cell-powered CHP units) have the potential to supply about 30%–40% of the United Kingdom’s energy demand, which would significantly contribute to the United Kingdom reaching its 80% carbon emissions reduction target by 2050. Early fuel cell vehicle research is very promising and the successful demonstrations have created innovative hydrogen energy markets for the transportation industry. Some examples are backup power units for existing vehicles, buses, forklifts, LDVs, scooters, etc. Pike research has reported that industrial forklifts could be the major contributor to hydrogen fuel demand in the United Kingdom by 2020, since most industries aim to find novel, affordable, energy-efficient, clean, and reliable methods to limit their costs, as mentioned earlier. In the United States alone, more than 8200 fuel cell components and pieces of fuel cell handling equipment have been manufactured since 2009. Taking advantage of the fuel cells’ durability, reliability, shorter refueling times, and less frequent refueling demands, fuel cell forklifts have shown reasonable payback periods and better cost efficiency with respect to the battery-powered forklifts currently utilized in indoor warehouses . Stationary fuel cell applications can provide small- and large-scale power from the kilowatt to even megawatt scale and these systems are currently utilized to supply power to isolated locations that have no access to the grid or for backup purposes. Fuel cells can also be utilized to supply the power demands of a variety of telecommunication applications, such as data centers, networking equipment, telecommunication towers, etc. in a robust and reliable manner. In many applications, such as the ones mentioned here so far, fuel cells frequently substitute for diesel generators. This significantly reduces the emissions of the power generation systems and provides extended lifetimes along with fewer maintenance requirements. For every type of end-user need, there is a fuel cell type available in the hydrogen energy market. For example, portable and/or smaller energy systems with output electricity capacities up to several kilowatts do generally use proton exchange membrane fuel cells (PEMFCs). Comparatively larger (and generally more stationary) energy systems with output electricity capacities up to the megawatt scale generally utilize more stationary high-temperature fuel cells, for example, molten carbonate (MC) or solid oxide (SO) fuel cells. There are many other fuel cell systems and some of them use natural gas, while others usually use hydrogen as the primary fuel. However, there are other liquid fuels that can be used in fuel cells, for instance, diesel, ethanol, kerosene, liquefied petroleum gas (LPG), methanol, etc. There are also some gaseous fuels used in fuel cells, including biogas, butane, coal syngas, propane, etc. Stationary fuel cells are generally more commonly accepted by the public compared to portable fuel cells. For example, in 2013, stationary fuel cells contributed to about 90% of all new fuel cell systems in the United States. The industry is currently very interested in expanding the hydrogen energy market as a result of diminishing fossil fuel resources and the requirements to reduce (if possible, eliminate) GHG emissions. A very possible method to incorporate hydrogen into the current energy market could be achieved via mixing it into the existing natural gas delivery systems and distributing it using the existing natural gas grid. The International Gas Union (IGU) has indicated that substituting 10 vol% of a natural gas supply with hydrogen cuts CO2 emissions by about 3%. Another study conducted by NATURALHY has presented that around 15% CO2 emissions cutbacks can be attained with mixing up to 50 vol% hydrogen gas into the existing natural gas grid. The CO2 emissions reductions are limited when mixing hydrogen with natural gas, because of the low density and low energy density of hydrogen. It is essential to note that many governments do not permit 50% hydrogen and 50% natural gas mixture by volume. This is limited to 25 vol% on a Wobbe number basis. In the meantime, the limit on hydrogen and natural gas mixtures is currently stated as 0.1 M% in many codes and standards. The Wobbe is a measure of the interchangeability of fuel gases when introduced into a heater via a burner with a fixed differential pressure. Two gases with the same Wobbe Index will deliver the same amount of heat into a combustion process per unit of time regardless of the composition. When deciding on whether or not it is beneficial to add increasing amounts of hydrogen into the existing natural gas grid, all potential effects should be considered thoroughly, including the effects on:

• Net and overall energy densities: increasing the amount of hydrogen in the mixture reduces its energy density.
• Wobbe number: increasing the amount of hydrogen in the mixture (up to around 70 vol%) reduces its Wobbe number slightly (it should be noted that this might not be regulated in some countries).
• Ignition characteristics: increasing the amount of hydrogen in the mixture reduces its “knock tendency.”
• Burning velocity: increasing the amount of hydrogen in the mixture (up to around 30 vol%) increases its burning velocity.

It should be noted that there are possible risks related to mixing hydrogen and natural gas supplies. For example, there are reliability risks of the grid network and fuel processing sites that might seriously affect the operators. Another impact might be the performance decrease of household appliances. Frequency of explosions and the risk of fire hazard might increase as well. Increasing hydrogen amounts in the existing natural gas pipelines might increase NOx emissions. These are some of the risks associated with introducing (or increasing the amounts of) hydrogen in the existing natural gas grid. And, all the risks mentioned earlier should be comparatively and thoroughly assessed by considering the reductions in carbon emissions that can be achieved by mixing hydrogen and natural gas instead of using natural gas alone. In addition, natural gas can be utilized for distributed heat and power supply systems via stationary CHP systems together with hydrogen. The United Kingdom Hydrogen and Fuel Cell Industry (UKHFCA) has shown that by using fuel cell micro-CHP technologies to replace today’s traditional boilers, about 2.5 t equivalent of CO2 emissions can be reduced. This amount is equal to about 40%–50% of a typical European household’s annual carbon footprint. This clustering of hydrogen infrastructure for a successful hydrogen energy market is being pursued by many researchers, scientists, politicians, and people from various industries. One common goal is to develop a clustered assembly of hydrogen fueling stations in order to be served during the start of FCEV utilization. For example, a recent study convened by the US Department of Energy (DoE) identified Los Angeles and New York City as the best early markets for hydrogen FCEVs [75]. Once fuel cell vehicles are successfully deployed in big urban regions, FCEVs could then be distributed gradually to smaller cities and eventually to more rural areas. For instance, FCEVs are first planned to be used in 20 key metropolitan regions in the United States. Then, the hydrogen infrastructure is planned to be expanded to smaller cities, interstate regions, and ultimately all the way through the United States. The fundamental action steps toward the development of an effective hydrogen fueling infrastructure are presented in Figure.