A HARD NUT TO CRACK
While ‘hydrogen in water out’ fuel cells sound simple and good, dig a bit deeper and hydrogen faces many challenges as a ‘clean’ fuel for light vehicles, especially in Australia.
Most hydrogen is currently cracked from gas in a high energy-consuming and high Co2-producing process. The only way to produce hydrogen cleanly is to produce it from water using renewable energy. This uses a lot of water and a lot of energy. This is governed by the laws of chemistry and physics and will not change.
It then needs to be compressed or liquefied (using energy) and transported through what would be new, and expensive, nationwide hydrogen distribution infrastructure. And fuel cells are only 50 percent efficient, so in the end the consumer ends up paying a lot for energy consumption and losses at production, distribution and consumption. 100kwh of electricity generation and some 30L-plus of water are required to produce between 19 and 23kwh of electricity output from the fuel cell to power the vehicle to travel roughly 100km.
Compare that to battery electric vehicles. There is already an electricity generation network which is transitioning to renewables and a distribution network throughout the country to plug in to (in almost every home). And batteries are very efficient at storing and releasing energy.
So every 100kwh of electricity generation produces 69kwh of electricity output from the battery to power the vehicle to travel more than 300km.
Which means a fuel cell vehicle owner will pay three times as much for hydrogen every 100km (assuming there is a hydrogen retailer) as the owner of a comparable battery electric vehicle.
Hydrogen, with storage innovations such as CSIRO’S, may make sense on an industrial scale for export similar to LNG (although I am not sure where the water would come from) but it’s hard to see how they have a future for light vehicles, especially with battery energy density rising and costs falling quickly and battery electric vehicle sales taking off while fuel cell vehicle sales are effectively zero. Mitchell Smith via email