[DriftRegion]

Hydrogen electrolyzers perhaps makes sense as a backup load: something that can be turned on when there's too much electricity production (as is increasingly the case in renewable-heavy grids). But then what to do with the hydrogen?

Fertilizer? sure. Heating? maybe.

Cars? the infrastructure still has a long way to go. See https://www.reddit.com/r/Mirai/ for the deets.

[zonkerdonker]

I agree that is a better use for excess power than just dumping it into a resistor, but why go through all the extra effort? Batteries are getting better and better and better, and choosing to use excess generated power to generate hydrogen seems like one step backward. Why waste so much power on a doubly inefficient process (losses from hydrogen production and then again during use) when you could just, you know....store the actual pure energy you need for everything else?

Even barring a great battery, there are dozens of other great ways to store energy. Pumped hydro is 80%+ efficient, and all you need is a pump and a hill, vs hydrogen electrolysis, which maxes at 80% efficency, and then hydrogen combustion, which is like 40%, on top of all the exotic equipment required for manufacturing.

By all appearances, it just seems like an absolute no brainer....I really dont get it

[DriftRegion]

> By all appearances, it just seems like an absolute no brainer....I really dont get it

I understand the policy around hydrogen (Bipartisan Infrastructure Law allocated $8 billion to hydrogen production) as a technological pivot for the United States which leads the world in oil and gas extraction and logistics tech. The US has a lot of gas handling experience.

Optimistically, green hydrogen will diversify the energy supply, bringing "energy resilience", a key policy buzzphrase. Batteries and pumped hydro are undeniably superior in round trip efficiency, but hydrogen does have some desirable properties such as relative ease of overland transport, very long term storage, and being a chemical precursor for some industrial processes.

Pessimistically, green hydrogen is a way for oil and gas companies to siphon many taxpayer dollars while doing superficial work similar to the compliance EVs of the 90s and 00s.

I'm optimistic mainly because my PhD in electrical engineering is being funded partly with the green hydrogen taxpayer dollars. Shout-out to my fellow taxpayers and my advisor's grant writing skills! I'm working on power electronics which are fundamental in renewable energy and by extension green hydrogen electrolysis.

[ephbit]

> ... bringing "energy resilience", a key policy buzzphrase.

The word "buzzphrase" implies that you think energy resilience is not as relevant as the proponents want to make it seem. Correct?

I've been thinking for years that resilience of the overall energy system is a factor that many green energy transition people appear to systematically overlook.

As I see it, chemicals based energy systems have a huge advantage over electricity based energy systems through their property of bringing large amounts of storage (and thus capacity to bridge outages) with them basically inherently.

The electrical grid is a delicate life support system and I'm convinced that it will - even in the far future - depend heavily upon chemical energy storage and transportation to give it resilience.

As far as I've heard the electrical grids in the US and Europe have come close to breaking points a lot more often over the last few years, compared to before. And even though huge sums of money are being invested in their build-out and maintenance, the supply situation with critical components such as transformers is apparently dire.

Alltogether makes me think that chemical energy storage (and thus, hydrogen, power-to-gas, ammonia, and such) will have a dead-sure place in energy systems.

[zonkerdonker]

Very enlightening! I appreciate the reply. Hydrogen as a sort of stepping stone away from gas and oil makes sense, as does creating another pillar for energy resiliance.

[hulitu]

> Batteries are getting better and better and better

They are still too heavy. Carrying a ton of battery every time doesn't really makes sense.