Since the Tokyo Auto Show, hydrogen has once again become a hot topic in “green” vehicles. Both Toyota and Honda showed a hydrogen-powered vehicle. Soon, Hyundai is releasing a fuel-cell vehicle to the public.
But what is a hydrogen-powered or fuel-cell vehicle? It’s an electric vehicle that, instead of a battery, uses a specialized fuel cell to fuse atoms of hydrogen with air (specifically the oxygen in the air) to make water and electricity — the reverse of hydrolysis. The exhaust is water vapor. Sounds great, right?
Well, getting the hydrogen from water (hydrolysis) requires electrical power. If this electrical power is from solar sources, then it’s still 100% clean energy. Some of the electrical power is lost during hydrolysis, making the process far from 100% efficient.
Next is the cooling of the hydrogen so it can be transported and stored. Cooling hydrogen to around -432 degrees F takes a lot of electricity. Again, we have a loss of efficiency.
At the fueling station (which also must keep the hydrogen at near 0 Kelvin — another loss of efficiency), pumps have to pump the fuel into the vehicle. Another loss of efficiency.
Finally, the car must fuse the hydrogen and oxygen atoms to make electricity. Another loss of efficiency.
At the end of the equation, we have around 30% efficiency. Still better than gasoline, but far from as good as an electric car. Like Elon Musk said, “Hydrogen-powered vehicles are so bullshit.”