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Hydrogen Fuel Cell Buses

Fuel cell technology dates back to the 1830’s. Fuel cells use compressed hydrogen to generate electricity by means of a chemical reaction. They have been successfully employed in large stacks of cells for stationary power generation and in space applications, and were first employed to power a road vehicle in 1966. The only in-street emission released by a fuel cell vehicle is water vapour.

Despite their relative success in stationary power generation, fuel cells have never gained popularity in motive applications and must still be considered to be experimental or in development. There are several basic reasons for their lack of popularity: 1) fuel cells are sensitive to impurities in the hydrogen, and the failure of one or more cells on board a vehicle can drastically effect power; although reliability has improved, it is not on par with that of a gasoline vehicle; 2) fuel cells are much less energy efficient than batteries, consuming about 2.4 to 3 times more energy per km than a battery-electric vehicle, making them less economical; 3) hydrogen refuelling infrastructure is not widely available and is costly to install and supply.

Hydrogen is not a naturally occurring resource and must be manufactured. It is only considered a “green” fuel if the hydrogen is made from renewable energy sources. Much of the commercially available hydrogen today is actually sourced from fossil fuels, such as natural gas, and is therefore not “green”; leaked hydrogen also poses an issue, as it has a global warming potential about 11 times greater than CO2.

A tremendous amount of energy is required to extract or isolate hydrogen from natural compounds (like natural gas, water, etc.), such that by the time the hydrogen is converted to motive power in the vehicle, so much energy has been lost that you only have about 1/4 or 25% left. For this reason, many have regarded fuel cells as a “non-starter” in terms of their potential to become a major power source for the future. Scientists at Stanford University and the Technical University of Munich have stated that “investing in all-electric battery vehicles is a more economical choice for reducing carbon dioxide emissions, primarily due to their lower cost and significantly higher energy efficiency.”1

Fuel cell transit buses have been in use in small numbers since 2000. Experience with them has shown that, while they are able to function in transit service, they are very costly to buy, maintain and operate. Their on-board systems are very complex, even more so than those of a battery-electric vehicle, and therefore there is much greater potential for component failure and a higher maintenance requirement. BC Transit operated a fleet of 20 fuel cell buses for the 2010 Olympic Games in Whistler and found their maintenance costs to be double those of a diesel or trolley vehicle, and their operating costs to be about three times that of a diesel bus or electric trolleybus. The fleet was disposed of after the Games had concluded. The community of Pau in southern France operated 8 fuel cell buses from 2019-2023. While some operating costs may have come down since the B C Transit experience, the Pau operator found the vehicles to be a constant challenge to keep running and abandoned them due to their high maintenance requirements.2

What the future will hold for fuel cell buses is uncertain. There may be technological improvements, but whether those would be enough to make them truly viable is difficult to say. At the present time, making large investments in a fuel cell bus fleet would not appear prudent.

1 - “Battery Electric cars are a better choice for emission reduction”, PV Buzz, November 15, 2016 (accessed at: https://pvbuzz.com/electric-cars-better/)

2 - Michael Barnard, “Hydrogen Fleets Are Much More Expensive To Maintain Than Battery & Even Diesel”, https://cleantechnica.com/2024/01/26/hydrogen-fleets-are-much-more-expensive-to-maintain-than-battery-even-diesel/ , January 2024 (accessed February 26, 2024)