The hydrogen-powered fuel cell car comes off well among alternative vehicle technologies in the most recent (June 2016) analysis by the Chicago-based Argonne National Laboratory. The cradle-to-grave lifecycle study of light-duty vehicle options, which involved three U.S. automakers, four major energy companies and the Electric Power Research Institute (EPRI), reported significant greenhouse-gas reductions with a fuel-cell drivetrain.
The Argonne study showed that an average midsize internal-combustion car produces 457 grams of carbon dioxide equivalent per mile (with all factors considered), compared to 316 grams for a fuel-cell electric getting its hydrogen via steam methane reforming. That’s a 31 percent reduction in greenhouse gas.
That conventional midsized sedan achieves 26.2 mpg, compared to 54.1 mpg equivalent for the fuel-cell vehicle.
Further, adds Amgad Elgowainy, principal energy systems analyst in the Energy Systems Division at Argonne, “Excluding vehicle manufacturing cycle impacts and focusing only on the fuel cycle or well-to-wheels, the greenhouse gas emissions for a conventional mid-size gasoline internal combustion engine vehicle is 413 grams of carbon dioxide equivalent per mile, compared to 250 grams per mile for a fuel-cell car powered by hydrogen produced via steam reformation of natural gas. This represents a 39 percent reduction in greenhouse gases for fuel-cell vehicles.”
As Elgowainy pointed out, the Hyundai Tucson, a small hydrogen SUV (available for lease), is rated by the EPA at 50 mpge, and the Toyota Mirai (available for purchase) at 66 mpge.
The Argonne report concluded that high-volume production is essential for bringing down the cost of all alternative-fueled vehicles, including fuel cells. It said, “Significant technical barriers still exist for the introduction of some alternative fuels. Further, market transition barriers—such as low-volume costs, fuel or make/model availability, and vehicle/fuel/infrastructure compatibility—may play a role as well.”
Argonne has offered, since 1996, the GREET model to allow fleet buyers and others to “fully evaluate energy and emission impacts of advanced vehicle technologies and new transportation fuels.” GREET stands for “Greenhouse gases, Regulated Emissions, and Energy use in Transportation.” A 2010 well-to-wheels analysis of hydrogen fuel-cell vehicles, based on GREET data, is here.
Other lifecycle analysis also looks favorably on the ability of fuel cells to reduce lifecycle climate emissions, especially if hydrogen is produced from clean sources. According to a 2011 well-to-wheels analysis for the European Commission Joint Research Centre, “Hydrogen from non-fossil sources (biomass, wind, nuclear) offers low overall greenhouse gas emissions.” The challenge, it said, is in actually producing zero-or low-emission hydrogen.
A 2013 National Renewable Energy Lab report on 10 potential hydrogen pathways concluded that “all of the pathways except distributed electrolysis result in greenhouse gas emissions (on a gram per mile basis) lower than 400 grams per mile based on a fuel economy of 48 miles per gallon of gasoline equivalent (mpgge), and below 250 grams per mile when a fuel economy of 68 mpgge is considered.”
The Center for Climate and Energy Solutions wrote that a midsized car using hydrogen produced from natural gas “is projected to have lifecycle greenhouse emissions slightly lower than that for a hybrid electric vehicle (HEV), powered by gasoline….A fuel-cell vehicle would have near-zero lifecycle greenhouse gas emissions if the hydrogen were made, for example, from electrolysis powered by renewable electricity.”
The Center also said, “Because fuel-cell vehicles are more energy efficient than vehicles powered by gasoline and because hydrogen as a transportation fuel can have much lower lifecycle greenhouse emissions than fossil fuels, fuel-cell vehicles have the potential to dramatically reduce greenhouse gas emissions and other air pollutants from the transportation sector.”