This piece is a sequel to, “Are Hydrogen Fuel Cells Vehicles Dead on Arrival?” What follows is a deeper look at the infrastructure, specifically hydrogen fueling stations, needed to support fuel cell electric vehicles (FCEV).
“Though hydrogen fuel cells have become much smaller, cheaper, and infinitely more efficient over the years, the technology has remained stuck on a road to nowhere. “With electric car sales not living up to expectations, the carmakers are looking for a hedge to meet the standards in California, and hydrogen provides that,” says Kevin See, a senior analyst at Lux research. But the biggest challenge facing fuel-cell cars today is the same as it’s always been — a lack of infrastructure. Only a handful of hydrogen filling stations exist in the U.S.,” according to Brian Dumaine reporting for CNN Money. What exists is a Catch 22 situation – need hydrogen cars to justify building fueling stations, but you need hydrogen fueling stations to justly purchasing fuel cell electric vehicles.
“Hydrogen-powered electric vehicles represent the next generation of electric vehicle technology,” said John Krafcik, President and Chief Executive Officer of Hyundai Motor America, Figure 1.
“The technology is here and automakers are ready,” said Catherine Dunwoody, executive director of the California Fuel Cell Partnership (CaFCP). “Before they can sell or lease fuel cell electric vehicles, a much larger fueling infrastructure must be in place.”
The prospect of alternative fueled vehicles running on hydrogen hit roadblock after roadblock ever since former U.S. Senator Masayuki Matsunaga’s vision of a hydrogen economy led to passage of the Hydrogen Research, Development, and Demonstration Act of 1990. One only has look back to 2009 when former Secretary of the U.S. Department of Energy Dr. Steven Chu announced that the government would cut research into FCEVs. Biofuels and batteries, he said, are “a much better place to put our money.” Nature reports, “The move came as a relief to the many critics of hydrogen vehicles, including some environmentalists who had come to see Bush’s hydrogen initiative as a cynical ploy to maintain the petrol-based status quo by focusing on an unattainable technology.”
The proposed budget cuts served only to galvanize supporters of hydrogen fuel vehicles and car manufacturers investing in biofuels and batteries. They feel hydrogen fuel cells have a long-term potential and are a way to satisfy stringent zero-emission vehicle (ZEV) mandates. Ultimately, Congress voted to override Chu and restore funds for hydrogen research, development, demonstration and deployment.
The push by the federal government to support commercialization of ZEVs turned towards lithium-ion battery technology. In many ways this was a logical move with the success of lithium-ion batteries in the consumer and computer electronics industries. Lithium-ion technology “is one of the most popular types of rechargeable battery for portable electronics, with one of the best energy densities, no memory effect, and a slow loss of charge when not in use; even modest increases in a battery’s energy-density rating — a measure of the amount of energy that can be delivered for a given weight — are important advances,” according to Lithium Air Industries, LLC.
Nevertheless, lithium-ion batteries do present a series of issues in terms or range anxiety (fear of being stranded with a dead battery), performance in cold and warm climates, and life expectancy. Tesla seems to have worked around the anxiety issue with the addition of a free Supercharger. Tesla claims “Superchargers allow Model S owners to travel for free between cities along well-traveled highways in North America and Europe. Superchargers provide half a charge in as little as 20 minutes and are strategically placed to allow owners to drive from station to station with minimal stops.” See Lithium Air Industry’s website for specific disadvantages with lithium-ion technology.
Yet interest in a hydrogen economy and hydrogen fueled vehicles remains mostly under the radar and on life support. Pundits see hydrogen as the only long-term solution to achieve energy independents and a zero-emission transportation industry. Critics still view hydrogen development wasteful government spending and another Solyndra.
The challenges with FCEVs seem formidable and the solution untenable, Figure 2. Converting skeptical customers into buyers depends on affordable and reliable fuel cells, competitively priced hydrogen fuel and readily accessible fueling stations. But, like any emerging technology, fuel cell vehicles, the next innovation in green technology, and hydrogen fueling stations have presented a chicken and egg dilemma: Which comes first? In this classic war of wits, it’s the fueling station.
Building a robust infrastructure for hydrogen transport, distribution and delivery to thousands of fueling stations seems an impossible task. Because hydrogen is the smallest molecule there is, it possesses unique properties that requires expensive pipeline materials and compressor designs. In conjunction with its low energy density, a hydrogen network is capital intensive.
However, over the last decade, advancements in fuel cell technology and hydrogen production have made a positive impact on the marketability of FCEV. The price of hydrogen fuel cells has declined steadily since 2002, and the range and reliability have increased. Fuel cell costs are moving closer to DOE’s target of $30 per kW at which point they will be cost‐competitive in light‐duty vehicles.
Brian Dumaine reports in the September 2, 2013 issue of Fortune, “Right now hydrogen is two to three times as expensive as gasoline on a per-gallon-equivalent basis. But because fuel cells are twice as efficient as gasoline engines, hydrogen fuel is only slightly more expensive. The DOE report concluded that, at scale, hydrogen could quickly cost less than gas.”
“My, at the pump price of hydrogen is about $15.00 per kg; about 2-1/2 times that of gasoline. Depending on who it comes from and how the hydrogen is generated, my cost from the supplier could range anywhere from $4.00 per kg if produced from natural gas by steam reforming to $18.00 if produced from water by electrolysis,” said Daniel Poppe, vice president, Hydrogen Frontier Inc.
Hydrogen can be generated at a central facility or on-site by a number of production methods.
- Steam Methane Reforming – High-temperature steam is combined with methane in the presence of a catalyst to produce hydrogen. This is the most common and least-expensive method of production in use today, Figure 2.
- Electrolysis – An electric current is used to “split” water into hydrogen and oxygen.
- Gasification – Heat is applied to coal or biomass in a controlled oxygen environment to produce a gas that is further separated using steam to produce hydrogen.
- Renewable Liquid Reforming – Ethanol or biodiesel derived from biomass reacts with steam to produce hydrogen.
- Nuclear High-Temperature Electrolysis – Heat from a nuclear reactor is used to improve the efficiency of electrolysis, again splitting water to make hydrogen.
- High-Temperature Thermochemical Water-Splitting – Solar concentrators are used to split water.
- Photobiological Microbes – Certain microbes produce hydrogen as part of their metabolic processes. Artificial systems can encourage these organisms to produce hydrogen through the use of semiconductors and sunlight, improving their natural metabolic processes.
- Photoelectrochemical Systems -These use semiconductors and sunlight directly to make hydrogen from water.
Electrolysis of water can use low-carbon energy sources including renewables to make hydrogen generation essentially zero emissions. Hydrogen is not an energy source, but an energy carrier because it can be oxidized in a fuel cell to generate electricity. The fuel cell combines hydrogen and oxygen to form water and oxygen. That is hydrogen generated from water during electrolysis produces water in the fuel cell, i.e., water to water. This is as clean as it gets.
Hydrogen fueled cars reportedly get an average of 60 miles per kg of hydrogen. The high efficiency of these vehicles tends to compensate for the high retail price of hydrogen, making it competitively priced gasoline. The industry is close to a price structure twice that of gasoline, at which point hydrogen starts to have a price advantage, according to Poppe.
To understand what 60 miles per kg of hydrogen means in terms of gallons of gasoline, a value called energy equivalents is used to compare different fuels. Energy equivalent is the amount of an alternative fuel it takes to equal the energy content of one liquid gallon of gasoline. For example, a typical gallon of gasoline has an energy content of about 114,000 BTU per gallon. Using standard conversation formulas, 114,000 BTUs equals 33.4 kWh (kilowatt hours). This means that one gallon of gasoline is equivalent to 33.4 kWh of electricity.
In a similar way, the energy content of one kilogram of hydrogen gas converts to 33.4 kWh. Therefore, one kilogram of hydrogen gas (33.4 kWh) has the same amount of energy as one gallon of gasoline (33.4 kWh), i.e., 1 Kg of H2 gas = 1 gallon of gasoline. (Note, it is happenstance that both 1 kg of hydrogen and one gallon of gasoline equal 33.4 kWh.)
Using this relationship, 60 miles per kg of hydrogen equals 60 miles per gallon (mpg) of gasoline. (The energy content of 60 kg of hydrogen equals the energy content of 60 gallons of gasoline.) Therefore, a hydrogen car rated at 60 miles per kg requires 4 kg of hydrogen to go 240 miles between fill ups. In the same token, a non-hybrid gasoline car rated at 25 mpg traveling 240 miles requires about 10 gallons of gasoline. The difference between 4 kg of hydrogen and 10 gallons of gasoline to go the same 240 miles is due to the higher efficiency of a fuel cell versus and internal combustion engine. The gasoline car wastes 6 gallons of gasoline and loses 684,000 BTUs of energy to go the same 240 miles.
With federal incentives drying up on the fuel side of the value chain, a powerful way to incentivize FCEV market is through cap-and-trade programs employing carbon credits. The evolution of a viable cap-and trade program in the U.S. goes back to 2006 with California’s Global Warming Solutions Act. The Act calls for a ten percent reduction in the carbon intensity (CI) of transportation fuels by 2020, where CI is in grams of carbon dioxide equivalents (gCO2e) per unit energy (MJ) of fuel.