One could imagine a series of cloudy windless days in the northern latitudes during the winter. Perhaps a large enough gird solves that problem? I have no clue.
One would not use batteries for the "rare, but prolonged" storage use case. You'd want something with lower capital cost, even if it were much less efficient. For example: hydrogen burned in turbines.
Hydrogen storage remains in the prototyping phase. We have no significant amount of hydrogen grid storage. Like thermal batteries or synthetic methane, hydrogen represents a potential storage solution but not one that we know will scale and be effectively deployed at the scope required.
If we actually deploy 50 GWh of hydrogen storage, and demonstrate that it can cheaply and reliability be built at scale then your point would be valid. But until then, hydrogen represents a theoretical solution not an actual solution.
Hydrogen is stored underground in Texas salt formations at Clemens Dome, Moss Bluff, and Spindletop. The largest of them, Spindletop, was completed in 2017:
All the components of hydrogen, with the possible exception of low cost electrolyzers, don't need to be prototyped. It's existing technology. It's not like (say) molten salt reactors, in which fundamental development remains to be done.
Right, and what company can I call right now to install 50GWh of hydrogen storage?
It's existing technology, but it's a novel application of that technology. We haven't used hydrogen electrolysis as a form of grid storage before. And we certainly haven't used it for grid storage at the Terawatt hour scale. And that the scale we'll need to make wind and solar viable. 1 TWh isn't even 30 minutes of global electricity consumption.
50 GWh of hydrogen would fit in one salt cavern of the kind already made for natural gas. Any numbers of companies can solution mine those caverns for you; that technology is many decades old. I'd need more information about the rest of what you want, as that scales by power not by energy capacity.
And are we currently using any of these caverns for electrolysis and grid storage? All you said is that we have a big cavern that we could fill with hydrogen. I'm asking if anybody is actually building hydrogen grid storage at any significant scale. Are there any facilities that take in excess energy from renewables, turn it into hydrogen, and then turn that hydrogen back into electricity?
We both know the answer: there aren't any.
Back in the 1950s people thought nuclear power would be cheaper than fossil fuels. They thought it'd be effectively free. The energy density of uranium is so much better, so clearly generating electricity with it would be much cheaper. But actually deploying a technology at scale reveals more and more challenges.
Your proposal for hydrogen storage is in the same phase that nuclear power was in during the 1950s. A solution that exists on paper, but one that hasn't actually encountered and overcome the challenges of implementing it at scale. Same with thermal batteries, synthetic methane, and so on. These are proposals that haven't passed the test of actual implementation at scale.
No, you have salt caverns with a volume sufficient to accommodate a lot of hydrogen. Actually implementing such a solution involves massive scale electrolysis, and either massive scales of oxidation cells or gas turbines designed to burn hydrogen. Neither of these things have been done at anything remotely close to the scale required to make renewables feasible.
Back in the 1950s people thought that nuclear power would be effectively free. But actually building it at scale exposed challenges of implementation that weren't foreseen. The cost of a system on paper and the cost after overcoming the challenges of actually building it are two very different things. For hydrogen storage, you only have the former.
Who pays for the shadow generation system that we keep perfectly maintained and ready to generate 100% of system demand on the 5 days stretch of cloudy windless days? This cost has to be added to the cost of building a 100% solar/wind system.
Nobody is arguing the solar and wind power isn’t cheap, but the cost of power on those cloudy windless weeks is going to be real high to make having all that standby generation around. It’s the cost to achieve the same reliability and 99% carbon free that is expensive.
Money is imaginary and global warming isn’t so let’s just print some bonds or move some numbers around in some database and build it all!
- an electrical power engineer
I guess not, but when two or three projects come in at the 10 billion cad mark it’s a pretty good sign that’s our cost to build. Not necessarily unique to hydro - we might have high cost to build anything
That’s a problem if you’re an island isolated from everyone else, and you don’t have geothermal, hydroelectric, or nuclear options. The better question is how much capacity you’d need on a national grid to be able to handle large regional sags in production without endangering people.
As we recently saw with Texas’ catastrophic fossil fuel production failures the big problem is not the source but poor management and not being able to get help from the neighbors.
But the key is that if you're averaging globally, the solar power probably doesn't change much. You'll need a way to transport the energy instead, obviously.