The energy content of hydrogen by volume is low. This makes storing hydrogen a challenge because it requires high pressures, low temperatures, or chemical processes to store it in a compact way. Fuel cell electric vehicles (FCEVs) combine hydrogen stored in a tank with oxygen in the air to produce electricity, with water vapor as a by-product. Unlike most common battery-powered electric vehicles, fuel cell vehicles don't need to be plugged in, and all current models exceed 300 miles of range with a full tank of fuel.
They fill up with a mouthpiece almost as quickly as traditional gasoline and diesel vehicles. Although fuel cell vehicles themselves only emit water vapor through their exhaust pipes, the Union of Concerned Scientists points out that the production of hydrogen can cause pollution. While renewable sources of hydrogen, such as agricultural and waste sites, are increasing, most of the hydrogen obtained as fuel comes from traditional natural gas extraction. However, the impact is still lower than that of their gasoline-powered counterparts.
According to the National Fire Protection Association, alternative fuel vehicles, a category that includes both hydrogen fuel cells and battery-powered electric vehicles, are no more dangerous than traditional internal combustion engines. The Canadian Hydrogen and Fuel Cell Association recently released a report praising hydrogen vehicles. There are dozens of fuel cell buses in use or planned in Ohio, Michigan, Illinois and Massachusetts, as well as in California. The hydrogen produced must be compressed, cooled and transported to the hydrogen station, a process that has an efficiency of around 90%.
As with any new technology, fuel cell costs should decrease if the market grows and achieves economies of scale in manufacturing and infrastructure. Fuel cells are attractive because, in theory, they overcome the efficiency limitations associated with traditional internal combustion engines. Leasing has been a popular choice among consumers for electric cars with fuel cells and batteries because the technology is new and early adopters don't want to be tied to a current model for a long time as technology advances and efficiency improves. I checked the source of the statistics, which revealed that they were comparing hydrogen produced from purely renewable electricity with electric vehicles powered by electricity from fossil fuels.
The hydrogen fuel cell electric vehicle (FCEV), which simply runs on pressurized hydrogen from a service station, produces zero carbon emissions from its exhaust gases. Honda and Toyota have partnered with a subsidiary of Shell Oil to build new hydrogen service stations in California. There are currently 39 public hydrogen stations in California (with another 25 under development), along with a couple in Hawaii. The co-founder and CEO of Tesla, Elon Musk, has dismissed hydrogen fuel cells as stunningly stupid, and that's not the only negative thing he's said about the technology.