Hacker News Reader

Comment by jryb | Hacker News Reader

I've always wondered why this kind of thing wasn't available much earlier. We've had electrolysis for a long time now - are fuel cells the limiting technology here? Are electrolyzers not as simple as I expect?

View on HN

They are only 20-30% efficient and have a low energy density compared to hydrocarbon fuel.

You need a massive amount of excess grid energy for it to make any sense.

Batteries were (are?) cheaper and you don't have to handle Hydrogen, which likes to explode.

I'm not an expert at all, but I was under the impression that hydrogen requires electricity for it to be synthesized. And that it's quite a bit more efficient just to use electricity in a battery directly instead of going through the process to create hydrogen, store it, and use it.

I do think it could be used in situations where the energy density benefits are important (planes, racing).

What do you believe is inside a standard battery? Pure electricity? That doesn't exist. It's a compound that goes through a chemical reaction when you charge it, and which goes through another one when you discharge.

"...lithium-ion batteries are 70-80% efficient, and hydrogen is only 25-30% efficient."

Source: <https://www.motorbiscuit.com/hydrogen-fuel-cells-vs-batterie...>

I don't see how that's relevant to what I said.

It's relevant to what I initially said. So I'm not sure how your comment relates. Maybe you just wanted to nitpick a word I used to sound smart?

Part of it is safety I imagine. Hydrogen can be nasty (e.g. blow up) if not handled correctly in the electrolyser design.

Reply on news.ycombinator.com