Hacker News Reader

Comment by WithinReason | Hacker News Reader

We have split natural seawater into oxygen and hydrogen with nearly 100 per cent efficiency

What % efficiency does "nearly 100% efficiency" mean in this context?

The paper is being widely discussed everywhere. I didn't get it (paywalled), but it seems the high efficiency claim means that way more than 95% of the electrical current goes into electrolysis.

Overall, the most important thing is that this thing is cheap. Everything else you read around just means it's equal or not much worse than the usual electrodes.

I read it as with exactly the same number of joules of electricity as the enthalpy of formation of the water they electrolyze (not sure about the terminology, it's been a while since I took chemistry). Basically the electricity supplies exactly enough energy to pop off the hydrogens.

I'd wondered the same, but even with that question hanging I think the outcome of being able to electrolyse sea water directly was interesting.

Seems like a good first step in desalination.

Seems more like a way to increase salination. Instead to me it sounds like a way to take solar and convert it into a hydrogen storage battery.

That is exactly what it does. This is a good thing. We can convert it into a fuel that can power vehicles and infrastructure. Yes, hydrogen is a scary element. Yes, hydrogen is hard to store. However, with water it is an abundant fuel source that should allow competition in conveyance and grid scale storage.

Reply on news.ycombinator.com