hydrogen powered cars have a significant potential to reduce emissions from the transportation sector, because they do not emit any greenhouse gases (GHGs) during vehicle operation. Their lifecycle GHG emissions depend on how the hydrogen fuel is made

A future mid-size car in the 2035-2045 time frame, powered by fuel cells and using hydrogen generated from natural gas, is projected to have lifecycle GHG emissions slightly lower than that for a hybrid electric vehicle (HEV), powered by gasoline. A fuel cell vehicle would produce 200 grams of carbon dioxide-equivalent per mi (CO2e/mi), compared to 235g CO2e/mi for a HEV. An FCV would have near-zero lifecycle GHG emissions if the hydrogen were made, for example, from electrolysis powered by renewable electricity.

Several major hurdles to commercial deployment must be overcome before any environmental benefits from FCVs are realized. These challenges include the production, distribution, and storage of hydrogen; fuel cell technology; and overall vehicle cost.

Hydrogen FCVs are a potential option for reducing emissions from the transportation sector. Combusting fossil fuels to power conventional vehicles releases GHG emissions and other pollutants from the vehicle exhaust system (i.e., “tailpipe” emissions). In addition, there are also emissions associated with producing petroleum-based fuels (i.e., “upstream” emissions), notably emissions from oil refineries. FCVs emit no tailpipe GHGs or other pollutants during vehicle operation, and depending on how hydrogen is produced, there can be substantially lower upstream GHG emissions associated with producing hydrogen fuel.

Fuel cells are already used to generate electricity for other applications, including in spacecraft and in stationary uses, such as emergency power generators. Although the concept of a fuel cell was developed in England in the 1800s, the first workable fuels cells were not produced until much later, in the 1950s. During this time, interest in fuel cells increased, as NASA began searching for ways to generate power for space flights

Hydrogen FCVs are considered one of several possible long-term pathways for low-carbon passenger transportation (other options include vehicles powered by electricity and/or biofuels). The benefits of hydrogen-powered vehicles include the following:

• High energy efficiency of fuel cell drivetrains, which use 40 to 60 percent of the energy available from hydrogen, compared to internal combustion engines, which currently use only about 20 percent of the energy from gasoline;2
• Diverse methods by which hydrogen can be produced
• Unlike all-electric vehicles (EVs), comparable vehicle range and refueling time to gasoline vehicles;
• Similar to EVs, quick starts due to high torque from the electric motor and low operating noise; and