Automakers give away free hydrogen because there is no way to charge for it
Over the years there have been a few vehicles sold by major automakers that are powered by hydrogen fuel cells. Burning hydrogen to produce electricity to power vehicles eliminates the pollution that burning gasoline produces. So far, all of these fuel cell vehicles have come with free hydrogen for the buyers of the cars. Free fuel is a big deal and if you though that automakers were doing that to sell the fuel cell vehicles, you are wrong.Toyota recently unveiled a hydrogen fuel cell powered vehicle called the Mirai H2 and announced that buyers of the vehicle would get free fuel for up to three years. This isn't being done to help make the vehicle more appealing to potential buyers, it's being done because there is no way to charge for hydrogen right now.
Currently it's impossible to accurately charge people for hydrogen according to representatives at the Mirai preview from hydrogen organizations. Hydrogen fueling stations aren't set up to accurately measure how much hydrogen is dispensed to consumers. Since accurate measurements can't be made and there are no standards for hydrogen, there is no way to charge people for the fuel.
The California Air Resources Board (CARB) is currently working on a way to sell a given amount of hydrogen, which doesn't currently exist. The challenge is how to guarantee that when a hydrogen buyer pays for a given amount of hydrogen, they are actually getting that amount. Being able to sell hydrogen is seen as a key factor to the success of fuel cell vehicles.
SOURCE: Autoblog