this post was submitted on 24 Apr 2024
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The operator I was reading was generating their own hydrogen. They spent something like $20k for a shipping container sized hydrogen generator - water and electricity in, hydrogen out.
What makes hydrogen expensive after up front costs?
The inefficiency.
If you need 100 kWh into the truck's electric motor to drive somewhere, with a battery electric truck you need to generate around 120 kWh at the power station. After transmission losses, transformer losses, charging and discharging the battery, etc you wind up with your 100 kWh.
If you're driving a hydrogen fuel cell vehicle, you still have an electric motor and you still need 100 kWh to reach your destination. But you need to generate something like 400 kWh to actually get 100 kWh into the motor, and that 400 kWh of generation and grid transmission is what you need to pay for. Turning electricity into hydrogen and back into electricity is incredibly wasteful.
This is hydrogens main problem.
It just costs so much more to make it.
There are some places in the world where it can be drilled for, eliminating some of the costs of production, but then you have to store and transport it. Hydrogen can't be stored easily (just big metal tanks), it requires pressure vessels made of exotic composites to reduce leakage, or worse cryogenic tanks that take a constant energy supply to stay cold.
Unlike nitrogen which we store as a liquid easily at industrial scales, hydrogen would be a nightmare to liquefy and store as any kind of scale. Nitrogen is liquid at -77 C, put it into a big metal tank and you are happy. Hydrogen is liquid at 20K (-253 C), metals are (mostly) to brittle at this temperature to be safely used. So exotic composites are required again to make cryogenic storage tanks.
The energy required to liquefy hydrogen is ridiculous, taking something to 20K is difficult and energy intensive.
I could go on, but beyond very specific use-cases hydrogen is a non-starter from a cost perspective.
You get a quarter of the energy you put in back out the other end, assuming you're using a fuel cell. And the entire system is horrendously expensive, even more so than an electric power train.
It's a stupid idea.