A hydrogen powered zero-emissions big rig in the Port of Stockton recently drew attention. However, some say hydrogen vehicles have a bigger carbon footprint than traditional vehicles, so what’s the point?
The problem is, hydrogen does not exist freely on its own. It takes energy to separate it. Plus it needs to be stored and transported in high pressure systems, and that takes more energy.
The most most practical source if hydrogen is from water–hydrogen and oxygen. But the energy needed to separate the two is the same as the power generated in the truck engine if done at 100 % efficiency. But there is no way this can be done at this efficiency. Then the hydrogen must be compressed to extremely high pressures and run through costly (because of the high pressures) distributions systems in order to be used This uses up more energy (which cannot be recovered)