Is Toyota’s Fuel Cell Vehicle Actually a Green Car?

Toyota Mirai

When the Toyota Mirai fuel cell vehicle debuts in 2015, it will be the first car of its kind on sale in a U.S. dealership and the symbol of the world’s largest automaker pushing back against battery electric vehicles. Yet few impartial people are willing to say hydrogen cars offer a cleaner ride than EVs at the moment. In fact, the technology needed to make fuel cell vehicles “green” compared to alternatives may arrive to your neighborhood much later than the Mirai will.

There are no emissions from the tailpipes of fuel cell vehicles. Instead, they only emit water vapor, which excites anyone expecting to see toxic smoke plumes coming out of a vehicle. Sometimes, you will see water drizzling from the tailpipe, but at no point are there carbon emissions. Unfortunately, this guarantee only applies to the car’s operation. Production of hydrogen fuel is not quite as clean.

Currently, most hydrogen used for fueling cars is produced from natural gas — the kind that takes hydraulic fracturing (i.e., fracking) when new sources are necessary. However, renewable sources are also used to procure hydrogen for fuel purposes. As an article by the Union of Concerned Scientists notes, California has mandated that at least 33% of hydrogen come from renewable sources, and the number will go up in the coming years.

As far as operation is concerned, a fuel cell vehicle produces far fewer emissions than a gasoline car, using a Hyundai Tucson crossover compared to the hydrogen model. Yet according to studies, production emissions are higher for fuel cell cars, which nearly evens out the benefits when matching a Toyota Mirai against, say, a Mazda6 that can achieve 40 miles per gallon on the highway.

David Becker/Getty Images
David Becker/Getty Images

A study by the University of California Irvine (appearing in August 2014) confirmed the near equivalent of gasoline cars and hydrogen fuel cell vehicles from “well to wheels” when using natural gas for production. Yet battery-powered EVs operating on California grid power were far greener than either option.

This study applies to the present day in California, which serves as the best model because fuel cell vehicles are only viable in The Golden State while hydrogen stations are scarce. In the future, this equation can change. Renewable sources for hydrogen — including solar, wind, bio gas, and other sources — have the potential to make fuel cell vehicles among the greenest things going.

A New York Times article on the topic pointed out a station in California that turns municipal waste (yes, that kind of waste) into fuel that can power 50 hydrogen vehicles a day. Other renewable sources of hydrogen continue turning up as well. Shell Oil recently funded a study where scientists produced hydrogen for fuel using corn husks and other types of biomass.

One day, hydrogen fuel cell vehicles may be some of the greenest cars on the road. When Toyota starts selling the Mirai in California, there will be much greener cars out there: battery electric vehicles. We promise to keep you posted whenever the equation shifts in either direction.