Essay: Hydrogen Fuel Cells

BY: Rupali Dhaul, Sam Preshaw, Will Thomas, Jade Yamanaka
Hydrogen fuel cell basics
What is a fuel cell
In today’s society, experts are continuously searching for new forms of renewable energy to minimize greenhouse gas emissions (GHGs). Among the many different causes for climate change in Canada, transportation is one of the leading sources, from individual locomotion to the shipping of goods1. However, experts believe that the emergence and budding popularity of electric vehicles in the recent years can greatly reduce the emission of these GHGs. Among the variety of electric vehicles, hydrogen fuel cell vehicles are becoming a viable option. Hydrogen fuel cells use hydrogen and oxygen as fuel to produce electricity, heat and water . Hydrogen fuel cells are intriguing as it requires the simplest and most abundant element on earth, hydrogen. 2
Hydrogen Fuel Cell Structure and Chemistry
Rather than utilizing the typical process of reforming to obtain hydrogens from hydrocarbons, hydrogen is instead obtained from water through electrolysis. Electrolysis is a process that induces chemical change by the passage of an electrical current through a solution.3
Fig 1: Schematic showing the basic workings of a Hydrogen fuel cell and the chemistry involved.Source: https://en.wikipedia.org/wiki/File:Fuel_Cell_Block_Diagram.png 4
All fuel cells are made of four major components: the anode, electrolyte, cathode and catalyst. Hydrogen, the fuel, interacts with the anode which consists of a catalyst, typically platinum. The platinum oxidizes hydrogen and splits protons and electrons from the fuel. Thereafter, the electron moves to the cathode via an external source which is often a wire, causing an electrical current to occur. Meanwhile, the protons migrate to the cathode through the electrolyte, which for instance can be potassium hydroxide. Additionally, the electrolyte is specifically used for the migration of positive hydrogen ions, moreover, the type of substance utilized here will determine the type of fuel cell produced. At the cathode, the protons and electrons eventually reunite and react with a catalyst, such as nickel, and oxygen to produce the by-product, water. Ultimately, hydrogen is consumed as fuel, electricity is created, and water is produced as the waste product. However, in order for this reaction to occur steadily, a continuous supply of fuel and oxygen is required. 5
The Different Types of Hydrogen Fuel Cells
As previously mentioned, although fuel cells have the same four major components, the type of electrolyte used in the system will determine the type of fuel cell produced, hence many different hydrogen fuel cells can be found. For instance, proton-exchange membrane fuel cells (PEMFCs) utilize bipolar plate, made of metals or graphite, which acts an electrode in the system, however, cost and maintenance can be an issue. Likewise, direct methanol fuel cells (DMFCs), similar to PEMFCs use a proton-conducting membrane as an electrolyte, however, uses methanol as the fuel source, thus making both carbon dioxide and water the waste products. On the other hand, phosphoric acid fuel cells (PAFCs), utilize phosphoric acid, an acidic non-conductive liquid, as the electrolyte, however, this can result in corrosion. Alkaline fuel cells (AFCs) on the contrary, uses a mixture of potassium hydroxide and water as the electrolyte. AFCs have notably been used by NASA in the Apollo space program. Additionally, molten carbonate fuel cells (MCFCs), utilize molten carbonate salts as an electrolyte to power certain industrial and military material due to its impressive efficiency. Lastly, solid oxide fuel cells (SOFCs) utilize a solid ceramic electrolyte called yttria-stabilized zirconia (YSZ) which are often designed as cylinders due to its composition. Each fuel cell has its advantages and research is still being conducted to produce the most efficient and environmentally conscious hydrogen fuel cell.
Fig 2: Table showing six different types of fuel cells and their relative operating temperature as well as their suitable application. Source: http://www.chfca.ca/education-centre/how-fuel-cells-work/ 6
Applications of hydrogen fuel cells
Transportation
There is currently a wide variety of vehicles that utilize hydrogen fuel cells to power their electric motors. The most common one is an FCV (fuel cell vehicle), and over the past few years, more car manufacturers have been investing in the production of these vehicles. Toyota, a current industry giant, revealed that in 2014 it would have cost about 1 million USD to make a hydrogen fuel cell powered electric vehicle, but thanks to rapid development of this technology, in 2015 can be made for as little as $50,000 USD, enabling consumers to seriously consider switching to this technology. When the technology was new, you could not actually buy an FCV; only lease one for a few years; due to the cost of the fuel cell technology within the vehicle. Another leader in the segment, Hyundai, currently leases its Tuscon FCV’s for $499 USD per month in a 3-year lease term, which includes a fuel card that provides free fuel to cover 12,000 miles per year. However, the main problem with FCVs is the lack of infrastructure, thus a company called “First Element” began installing hydrogen pumps at pre-existing gasoline stations, dramatically cutting down costs when compared to building a whole new station just for hydrogen.7
The other main method of transport that currently utilises this technology is electric buses, called fuel cell electric buses (FCEB). They are currently operating in multiple cities across the world and ultimately provide a clean and environmentally friendly method of transport for the masses. An advantage of FCEBs over battery powered electric buses is the efficiency, as a major problem with battery technology is its lack of effectiveness in extreme cold temperatures. Whereas hydrogen is much more stable and is not affected by extreme temperatures.
A third application for the fuel cells is in warehouses and manufacturing plants that require the use of forklift trucks and cargo handling machinery. Hydrogen fuel cells are powering this machinery and providing a clean alternative to gasoline or diesel-powered alternatives. Also, they have an advantage over battery operated units since there is no lengthy charging times which means that less units need to be bought in order to keep up with the workload.8
Transportation of hydrogen:
The initial storage and transportation methods of liquidized hydrogen consisted of steel tanks that kept the hydrogen in a liquid form at around 2000 PSI. This proved to be an effective way at storage, and since Hydrogen in not corrosive, there proved to be no problems with degradation of the steel containers. However, new advances in the storage of Hydrogen has lined the inside of these steel tanks with a carbon fiber composite material that vastly improves the strength to about 10 times that of steel alone and can even withstand a 100 MPH crash without breaking open. These advances in the handling of liquidised Hydrogen allows a safer transport of it to market and makes it a much safer and appealing source of energy.9
One of the current methods of transport of hydrogen to market is the sharing of a single pipeline, with both natural gas and hydrogen gas in one pipeline, where the two gases are then separated prior to use. This is a very efficient method of transportation given that the current infrastructure for natural gas already exists. As well, the presence of natural gas allows for a faster detection of a leak in a pipeline due to the odorants that are added to the natural gas. Also, a benefit is the maintenance of potential energy when compared to an energy source such as electric; as there is a certain amount of lost energy due to resistance in power cables over long distances. However, with hydrogen there is no loss in potential energy, and this makes it a cost-effective method of transportation.10
Hydrogen for consumer transportation is sold in various forms depending on the required energy demands and range of a single tank; there is 2 common and 1 less common forms of hydrogen that are used for transportation. The first is compressed hydrogen gas which is dispensed at either 5000 PSI or 10000 PSI. This is a common form for cars and buses. The other common form is cryogenic, super-cooled liquid hydrogen.
The third form of hydrogen is a liquidised slurry that is a hydrogen rich compound. Often it is lithium hydride or magnesium hydride that is used and is a promising form given that it can be stored at normal living temperatures and treated in a similar fashion as any other liquid given its higher stability. An application of this would see the slurry delivered to the gas station where it would be separated into pure hydrogen, and the byproduct (Mg(OH)­2 (milk of magnesia) can then be returned to magnesium hydride for re-use. The advantage of a slurry over cryogenic hydrogen is that it has twice the energy density and is much cheaper to produce and transport. 11
Stationary Fuel cells:
Stationary hydrogen fuel cells are static units that provide power and heat to a surrounding home or building. There are several types, of which include primary power units, uninterruptible power systems (UPS) and combined heat and powers systems (CHP).
The CHP systems provide up to 10 KWe and have an overall efficiency of up to 95%. These systems are very practical for use in the residential sector as well as apartment buildings, nursing homes and hospitals, and there have been greater than 10000 units launched in Japanese homes. The only limiting factor for the application in the residential setting is the cost; which in Japan and south Korea is offset by government subsidies. The fuel cell technology in these units relies on either PEM (proton exchange membrane) or SOFC (solid oxide fuel cell) technology.12
A recent study (Herrmann et al. 2018), investigated the cost efficiency of a CHP based hydrogen fuel cell and observing its current application in Germany. This European country is well suited to a hydrogen economy due to the second largest hydrogen pipeline being based here, as well as this, Germany gets about 35% of its energy from renewables13, which makes the production of hydrogen using this energy a very environmentally friendly option. As shown in Fig 3., Hydrogen produced by steam reforming of natural gas has the cheapest overall cost when applied to a CHP residential power system. Hence the reason why the European project ene.field is set to deploy up to 1000 CHP residential systems across 11 European countries.
The UPS systems are currently being applied to the use as a backup power supply to major telecommunications stations, data centers and residential use, in the event of a grid failure or interruption.
There is also large stationary units that are capable of providing multiple megawatts and are currently foreseen to be a replacement for a standard electrical grid, and its application looks especially useful in areas with little or no pre-existing grid infrastructure.14
Figure 3. The costs and revenues associated with many common heating sources in an average home. Source: https://www.cleanenergywire.org/factsheets/germanys-energy-consumption-and-power-mix-charts 13
Portable Fuel cells
Portable hydrogen fuel cells have many applications due to their ability to be easily transported and the range of sizes can offer a nominal voltage of between 8.4V to 36V and are currently available for sale at a price less than $6200 USD. These portable power units are currently being developed to deliver up to 500KW of power. Their applications include military use, small and large personal electronics as well as its use as an auxiliary power unit to provide power to trucking and camping industries.
There is also micro-fuel cells that are used to power personal electronics and are less than 5W. These units are becoming more popular, mostly due to their cost-effective means of obtaining power and their lightweight and versatility in various applications. 14
Environmental Impact
The environmental impact of the use of hydrogen fuel cells can be broken into sections by following the path from production to distribution of hydrogen, as outlined in the above graphic. The obvious appeal, in terms of environmental impact, of hydrogen fuel cells is that once . Figure 4: Hydrogen Supply Chain15 it has been distributed to the consumer there is no further impact since the only products of its combustion are water and heat. Additionally, the heat that is produced can be captured and utilized in some cases, and this may be an additional benefit of Hydrogen fuel cells if properly exploited.
The first step in the hydrogen supply chain is energy production, for use in the bulk production of hydrogen. There are many potential sources of energy which may be used, each of which has its own advantages and disadvantages. Beginning with renewable sources, biomass, which is the primary fuel source for gasification, can also be used as a fuel source to power other hydrogen production methods. It is the use of trees and/or other plant matter for combustion to produce heat which may be converted to electrical energy. The results of burning wood are not all bad, ash can be used as a fertilizer and although carbon dioxide and other undesirable compounds are released in this process, these compounds and specifically the carbon dioxide were taken out of the environment by the trees, which would not have been planted if biomass weren’t a viable fuel source. It is important to note that incomplete combustion results in various toxic, volatile, and/or carcinogenic compounds. Also to be considered is the transportation of trees to the “biomass boiler”. If done on a small scale this process may be minimally impactful, but large-scale operations require harvesting from a larger region which means more transportation needs.16 Overall biomass is an option and it being a renewable power source makes it appealing, but it is not a clean process by any means.
For wind, solar and hydroelectric energy sources, the environmental impact once the infrastructure is in place is very low or near none, however, the weakness is that they can generally only be placed in certain locations, so this is not viable everywhere. Biogas makes use of the waste humans produce, instead of looking to natural sources for fuel. Energy production using biogas involves the fermentation of waste from several sources, primarily including manure, agricultural waste, food waste, and municipal waste. One very positive aspect of this method is the consumption of unwanted waste and its applicability to so many kinds of waste. However, this wide array of sources leads to a large mix of compounds being present in this fuel source, meaning that when combustion occurs, even in an ideal complete combustion scenario there are still many unknown compounds being released. As well there is the consistent issue of transporting fuel to the site of combustion, and unlike biomass, it is highly unlikely that waste is being produced near this site, especially in the case of municipal waste.
Beyond their environmental impacts, the non-renewable sources are problematic simply in that there is only so much available, so dependence on these would be, and is a large issue. Beyond this, the specific types each have their own unique drawbacks and strengths which render them valuable in this discussion. In the United States, 65% of the coal produced in 2017 was through strip mining, and other methods include mountaintop removal and underground mining. Mountaintop removal uses many explosives, and both it and strip mining greatly deface their surroundings, and an additional issue with mountaintop removal is that the mountaintops contain more than coal, which leaches into local water supplies when the rubble settles. Underground mining releases large amounts of methane which is usually trapped with the coal, and additionally, acidic runoff can come from abandoned mines. Once the coal has been extracted it has to be burned to extract its chemical energy, which releases large amounts of a large mix of chemicals, including SOx and NOx compounds, which can lead to acid rain.17
Nuclear power, when it operates successfully, can be quite a clean fuel source since a small amount of fissile material can release massive amounts of energy. However, these materials must be extracted somehow, which carries many of the same concerns as coal mining, in addition to the radiation. There is little or no emissions from the use of these radioactive materials besides steam, depending on the style of reactor, but the expended waste does have to be dealt with. This waste can be stored either below ground or in a continuously manned facility, both of which, again, if successful, will prevent leakage of radioactive materials, along with the materials they’re stored in and/or with.18
Natural gas is commonly accessed through fracking, which is an environmental hot-button issue. The issues associated with fracking, however, are considered to be less significant than those for any of the techniques discussed above for coal. Beyond the extraction itself, all steps of natural gas production are bound to leak some amount of gas, to the point where nearly 32% of the total methane emissions from the united states came from these leaks. Once it has been extracted it then needs to be burned, either at the site of extraction or at some secondary location. Natural gas is a cleaner burning fuel than coal or distillate fuel oil, but it still does release large amounts of carbon dioxide, and smaller but significant amounts of sulfur dioxide, carbon monoxide, and others.19
Energy sources, while important and significant when examining the environmental impact of hydrogen fuel cells, is only the first step in the hydrogen supply chain. The next is the actual production of the hydrogen gas. There are three main methods by which hydrogen is produced and these are gasification, electrolysis, and steam methane reforming. Each of these has their own benefits, however, the environmental impact varies widely between them. Gasification is generally split between two main types; coal gasification and biomass gasification. Coal gasification is the easier of the two processes, but simply by being a non-renewable resource it is unsustainable in the long term. Biomass is generally the cleaner of the two as plant matter has a predictable structure, while coal is more variable as a function of where and when it was formed. Largely all that is formed is hydrogen, which is collected, and carbon dioxide and carbon monoxide, which can be converted to carbon dioxide and more hydrogen gas through a water-gas shift reaction. This carbon dioxide is an emission, but it is only the carbon which was initially removed from the atmosphere by the plants so it can be considered carbon neutral.20
Electrolysis, as discussed in the costs of hydrogen production section, is the most expensive method of hydrogen production currently in use, largely due to the large energy consumption. The large energy cost is reasonable however when electrolysis is looked at as the reaction which occurs in a hydrogen fuel cell to produce electricity but in reverse. This energy consumption may also have environmental connotations as discussed above, but if it comes from a clean, renewable source, electrolysis is extremely clean and despite the cost is environmentally the soundest.
Steam methane reforming is the most used method of hydrogen production in the United States, as much as 95% of the hydrogen produced is by this method. It involves the reaction of methane, usually from natural gas, with high-temperature steam. This process, after a water-gas shift reaction, yields only carbon dioxide and hydrogen as its products. However, this carbon dioxide release is significant, or alternatively, it may be stored through carbon sequestration, which is the storage of carbon dioxide underground.17
Once the hydrogen has been produced it often must be transported a distance to the site where it will be used. Notable exceptions include some stationary power sources, which may have associated hydrogen production equipment. This is a valuable case to consider, because not only does it rule out the environmental impacts of transporting the hydrogen, some of the energy produced by the hydrogen fuel cell can be used to power, at least in part, the hydrogen production. In an idealised scenario, this setup could run as a nearly zero-emission power source, ignoring water vapour. In the more common case of needing to transport the hydrogen some distance, there are a few options, which each have their own applicabilities: it can be transported in a pipeline, or in some vehicle. Vehicles are a good choice for smaller quantities because, despite their emissions, there is not an initial surge of pollution caused by having to build the infrastructure a pipeline requires, Conversely, a pipeline can seem like an environmental blight when viewed in the short term, but for very large volumes pipelines are the cheapest, safest and fastest method of transportation.
Depending on the intended purpose of the hydrogen that has now been produced and transported it will now either be used in a Hydrogen fuel cell, or it will need to go through a last step of distribution. In the case of Hydrogen fuel cell vehicles, distribution stations are required, analogous to gas stations for traditional vehicles. Similarly, to the case of gas stations, hydrogen refuelling stations must be conveniently accessible enough that consumers are not discouraged from choosing a Hydrogen fuel cell vehicle. However, there are costs, both fiscal and economic, associated with any new infrastructure, and especially in a case where so many discrete locations would be necessary to be effective.
Finally, the hydrogen has been produced and transported and distributed as required for the specific application, it is time to examine the environmental impacts of the hydrogen fuel cell itself: there is none. Of course, this is an oversimplification; the actual reaction of hydrogen with air-feed supplied oxygen releases only water and heat, which can be considered no environmental impact. Production of the fuel cell itself does carry some inherent weight, as any machinery does. However, the comparison here is between hydrogen fuel cells, and other electricity sources, for example, a traditional gas-powered car engine, not between a fuel cell and nothing, so these costs have not been investigated, as they are assumed to be analogous.
Current issues
Cost: Hydrogen Production
High capital costs for hydrogen production has been the major issue for the future of hydrogen fuel cells. Today, many hydrogen fuel production technologies are still too expensive to compete with conventional fuels. Most of the hydrogen produced today is through the use of fossil fuels such as natural gas and coal. The production of hydrogen through steam methane reformation (SMR), the most widely used method, costs approximately three times the amount the production of natural gas (NG) per unit of energy is produced21. The major issue with SMR technology is that the materials required for the reformers are uncommon and expensive. Not only are the parts costly, but reformer processing steps
are extensive and require many separations. Fig 5: Typical industrial cost and performance of hydrogen production technologies. Source:
Application of Concurrent Development Practices to Petrochemical Equipment Design, Franklin D. Lomax, Jr., Virginia Polytechnic Institute State University21
To overcome this, engineers must design reformers that can combine processes as well as incorporate low-cost components. Another barrier is that reformers are not being manufactured in large enough quantities to allow for higher volume production. The adoption of coal gasification (CG) technology, being 1.4-2.5 times more expensive22 than SMR, has economic barriers similar to SMR. One major issue is the need for continuous operation; CG requires extensive monitoring of its gasifier which has huge implications for the cost of operation. Temperature monitoring techniques are unreliable due to underdeveloped sensors and instrumentation. Another issue is the need for more advanced materials for gasifiers that can withstand the harsh coal environments.
Water electrolysis is currently one of the more expensive hydrogen production methods. Capital cost issues arise from expensive materials, smaller-scale systems, low efficiencies, and electricity required. Production costs are greatly affected by the requirement of expensive materials such as noble metals and the poor durability of the electrodes and membranes of electrolyzers. The major culprit for water electrolysis’ high capital cost is electricity. The process of splitting the water molecule is a harder task than imagined; chemical bonding forces between the hydrogen and oxygen are extremely strong, causing the lysis to be extremely energy intensive. This greatly affects the capital cost due to the low efficiency capabilities of the stack and system technology (efficiencies from 74% to 64% for low-temperature stacks)22. The high electricity requirement combined with barriers affecting the production of more efficient systems show why electrolysis is lagging behind the other hydrogen producing technologies.
Fig.6: High volume cost projections of the different methods of Hydrogen production. Source: https://www.energy.gov/sites/prod/files/2017/11/f46/HPTT%20Roadmap%20FY17%20Final_Nov%202017.pdf 22
Currently, the main goal of hydrogen production research is to develop ways of producing hydrogen more cost-effectively. The National Research Council has predicted a decrease in retail hydrogen prices from $10/kg in 2017 to around $4 to $6 per kilogram in 2025 ($/kg is equivalent to $/gge)25.
Cost: Fuel Cell Production
The cost of manufacturing fuel cells remains too high to compete with traditional fuel. For example, PEMFC, the most promising type of fuel cells that are expected to eventually fuel transportation, have current production costs that greatly exceed target prices. This makes them unlikely to substitute typical combustion engines for quite some time. To maintain fuel cell activity and efficiency, durable materials must be used for the fuel cell stack. The U.S. DOE investigated the cost analysis of a PEMFC
Figure 7. The percentage of various costs associated with PEMFC units depending on the number produced per year. Source: add website source here
stack for light-duty vehicles, indicating a 66% and 43% contribution to the total system cost (at 1,000 and 500,000 systems/year respectively)27. Further breakdown of the components at 500,000 systems/year show that the catalyst and application make up a whopping 41% contribution and bipolar plates a 28%. Platinum is typically used for building the catalysts and stainless steel for bipolar plates. Platinum is an expensive and volatile metal, being in limited supply in only a few countries. The DOE cost status of manufacturing a light-duty vehicle fuel cell system in 2015 (at 500,000 systems per year) was $17/kWnet with targets of lowering it to $14/kWnet by 2020.28
Figure 8:The overall materials cost associated with the various components in a hydrogen fuel cell. Source: add website reference
SOFCs, having operating temperatures up to 1000°C and varying atmospheres (oxidizing/reducing), also require expensive materials that are capable of withstanding the harsh fuel cell environments. The anode and interconnect dominate the overall price of the stack due to their mass and costly material. Figure (29) shows a 2003 cost breakdown of SOFC stack components: results show that the anode has contributions of 44% and the interconnect 45% of the total cost. Lanthanum chromite (LaCrO3), an expensive ceramic, is currently the standard material used for the interconnect due to its stability and relatively high electricalelectronic conductivity30. The anode, which is made from nickel-cermet, contributes largely to the overall cost due to its thickness. SOFC technology, despite having greater advances compared to PEMFC, also remains too expensive to compete with energy prices.
Durability and Hydration
Together with cost, durability is another major barrier in the commercialization of hydrogen fuel cells. Within the past 10 years, researchers have been focused on improving the durability of fuel cells. In order for hydrogen fuel cells to enter the marketplace, they need to be reliable. As mentioned before, the majority of the system cost comes from the catalyst. This catalyst must suffer “oxidation, migration, loss of active surface area, and corrosion of [its] carbon support.”31 Therefore, the use of high-grade materials such as platinum, that can withstand these factors, is essential to its stability. Fuel cells generally have constrained operating temperatures, but different types can cover different temperature ranges. This is because each fuel cell is characteristic of the electrolyte used. The electrolyte in PEMFCs not only determines the temperature range of operation, but also what kind of chemical reactions can occur within the fuel cell. Therefore, since low-temperature (~80°C) PEMFCs degrade when undergoing cycling at high temperatures, researchers must develop fuel cells that can withstand a broad range of operating temperatures. In sub-freezing temperatures (below 80°C), membranes begin to lose hydration resulting in decreased energy efficiency therefore a high-pressure hydration system is necessary for transferring hydrogen protons for the future of PEMFCs.
SOFCs, having stationary usages and operating temperatures as high as 1000°C, also effects durability. The lifetime of SOFCs are dramatically reduced due to the very poor sulfur tolerance (under 800°C) of the Ni-cermet anode32, making the use of SOFCs for automobiles unlikely at this time. Another issue is the sensitivity of the electrode, which has been found to degrade when contaminated by chromium poisoning from the interconnect33.
Delivery and Infrastructure
The delivery and infrastructure for hydrogen production go hand-in-hand. Unfortunately, the infrastructure required to achieve efficient application of hydrogen fuel cell technology is still being developed and still has many obstacles to overcome. The location of hydrogen production facilities greatly impacts the cost of delivery as well as is a determinant of which delivery method is the best. Packaging of hydrogen for send-off to fueling stations can occur by compressing it into pipelines, converting it into liquid for delivery by tanker trucks, or by rail or barge. One of the major issues with the delivery of hydrogen fuel by liquid tankers is boil-off. When the liquid hydrogen is left in the fuel tank for long periods of time, the hydrogen can evaporate. To prevent this, more robust fuel tanks must be used which provide super-insulation. Due to hydrogen being in liquid form, it must be held at minus 253 degrees Celsius. To maintain this during transportation in a fuel truck it requires a highly advanced system of freezers. As well, because it is so cold, the hydrogen can freeze the air around the tank (thus requirement for super-insulation). This makes liquid (cryogenic) hydrogen a less viable option. Therefore delivery of liquid hydrogen via tanker trunks is quite costly due to the energy required. The other delivery method, by pipeline, is most cost efficient for delivering larger volumes of hydrogen however it also has its disadvantages. The unappealing high initial capital costs for new pipeline construction makes the introduction of this infrastructure extremely difficult when people cannot see the long-term picture. A major issue with hydrogen delivery via pipelines are leaks and penetration. Hydrogen is capable of breaking down the steel and welds that line pipelines, leading to ruptures. When these pipelines rupture they almost always catch fire. Small leaks are hard to detect due to hydrogen’s lack of odor; this mixed with hydrogens extremely flammable and explosive nature when in contact with air makes this mode of delivery quite dangerous.35,36
Storage and Safety
When introducing hydrogen fuel cell technology, the issue arises of how to efficiently store the hydrogen and how to do so safely. Whether the hydrogen is required during peak hours for immediate automobile fueling or for future industrial purposes, storage lifetime must be able to vary. For conventional driving (greater than 300 miles), constraints such as weight, volume, efficiency, safety, and cost enter the equation. Since 2011, the U.S. DOE has primarily been researching how to lower hydrogen storage systems’ weight and volume with efforts of allowing driving ranges that can compete with petroleum fueled vehicles37. Currently, the maximum capacity for a hydrogen cylinder is 80Ma (800 bar) with pressure limits that require a 25L cylinder for a 300-mile range. To combat this, the development of more compact and lightweight components is required to provide ranges greater than 300 miles. Adding and removing hydrogen for reversible solid-state materials also poses many problems. As stated by the DOE, the “life-cycle energy efficiency is a challenge” because “byproduct is regenerated off-board [where] the energy associated with compression and liquefaction must be considered”. Consequently, 10% of energy stored in hydrogen is from the energy required to compress the gas38. The durability of the materials and components of these storage systems require a lifetime of 1500 cycles; however, current technology cannot provide adequate cycles. Lastly, the cost of producing on-board hydrogen storage systems is still too high compared to petroleum store systems. The need for cheaper materials in production and a higher volume of manufacturing is essential.
Two safety concerns regarding hydrogen fuel cells is the potential for electric shock via automobiles and flammability of the fuel. Due to newer vehicles requiring much higher voltage to power their electric motors, newer technology will need to develop higher current standards. Currently, standard automobile system voltages are 14V and in the process of being developed into 42V systems. Even some fuel cell vehicles can have voltages greater than 350V. Electric shock poses a great danger as voltages become greater than 50V (the amount of voltage to stop a human heart). Another safety concern is with the flammability of hydrogen gas. As mentioned earlier in issues with delivery and infrastructure, hydrogen is an odorless, colorless, and tasteless gas. There are no known odorants that are light enough to add to hydrogen therefore detection is almost rarely caught in time. Additionally, hydrogen is colorless so if fires and explosions occur, flames are invisible. This could have dangerous implications if hydrogen fuel cell automobiles get into accidents, requiring specialized protocols.39
Future of H fuel cells and our recommendation:
Currently there are many hydrogen fuel cell powered vehicles in California, which is mostly due to the large network of refueling stations located throughout the state. The projected increase in hydrogen powered vehicles is expected to rapidly increase over the next 15 years as studies have shown that the number of sales in 2017 was about 0.01 million vehicles, with an increase to 5.01 million by the year 2032.
By 2020, BC plans to have 8 hydrogen fuel stations to add to the existing two in Vancouver, including one in Victoria.40
Figure 9: The projected increase in sales of FCEVs from 2017 to 2032. Source: https://www.hydrocarbonprocessing.com/news/2016/09/hydrogen-fuel-cells-vehicles-are-future-of-automobile-says-report 40
Figure 10: This eludes to the increase in sales of hydrogen fuel cells globally in the past 8 years. The overall trend shows a decrease in the sales of portable fuel cells, but an increase in both stationary and transport-based fuel cells. Source: ttps://brandongaille.com/23-disadvantages-and-advantages-of-hydrogen-fuel-cells/ 41
With more and more companies investing in hydrogen technology, this supports the idea of a hydrogen powered future. many start up companies have received government grants in order to begin the process of designing safe and efficient ways to develop, transport and deliver hydrogen to the market. For example, “FirstElementFuel” recently received a 27.6 million grant from the California government to enable the building of 27 new hydrogen stations across the state.
Furthermore, pressure from environmentalists to decrease global CO2 production will see modern and clean technologies become dominant. Hydrogen is at the forefront of this movement and with the amount of investment, it will be readily available to the average consumer in the next 15 years. With consumers moving towards electric vehicles, the idea that you can fill your tank with hydrogen in a matter of minutes is very appealing when compared to the lengthy charge times currently imposed on drivers of electric vehicles. Provided that the hydrogen is made and transported in an economically and environmentally friendly manner (ie. developed using hydroelectric, solar or wind power), it will significantly contribute to a decrease in worldwide CO2 emissions. As fossil fuel reserves begin to decline, hydrogen production will step forward as a new means of energy production and will contribute greatly to the economy of whichever country can make it cheaply and export worldwide. Based on the above findings we would strongly recommend Hydrogen as a new alternative to fossil fuels, from both an economic and environmental standpoint. In conclusion, Hydrogen as a fuel source can certainly be an extremely environmentally friendly option, however, environmental impact is a complex issue, where a simple view of the functionality of the fuel cell itself is insufficient for an exhaustive discussion. Following the above breakdown of the hydrogen supply chain in figure 4, it can be seen that options exist to allow hydrogen to be extremely clean, or as bad as other fuel types, or even worse. It cannot therefore be definitively said that this is an environmentally friendly option, but the potential for it to operate as one is present and realistic.

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