Comment by gpm
4 months ago
The storage needed to turn solar into a reliable (as any comparable fossil fuel power plant) dispatchable source of power, plus the cost of the solar in the first place, costs less than other sources of dispatch-able power (like gas) in sunny places per kwh.
It also scales down better (though not perfectly).
Either you can afford it (both storage and solar), or you can't afford power at all, or you don't live in a sunny place.
Ignoring sunk capital costs into other energy infrastructure of course. If you already have a working nuclear power plant you're not going to save money by randomly turning it off and switching to something else, for instance.
Well, I certainly can’t make a couple weeks of battery storage pencil out vs. a fossil fuel generator at this point.
The math actually gets worse once you get into combined cycle natural gas at scale.
You I suppose could make an argument that load curtailment is cheaper than planning for the current grid reliability everyone has gotten used to over the past 50 years, but it would be a societal shift.
Seasonal energy storage is what is interesting to discuss, and of course is where that last 2% of grid reliability comes from. It’s also the most expensive part of running a grid. The first watts are basically free, the last are very expensive.
I’d love to be proven wrong within the next decade though! I just personally don’t see the battery storage price going down at the same rates it has been simply due to structural raw material input cost reasons - short of a breakthrough in chemistry. I think we are getting close to the maximum savings achieved by economies of scale with current technology.
You shouldn't need a couple weeks of battery storage - if you're in a sunny place. For example Las Vegas should be able to reach 97% uptime of constant energy supply (greater than your typical fossil fuel plants uptime) by building ~17 hours worth of storage and ~6x the amount of power needed in the nameplate capacity of the solar panels. Even a slight bit of curtailment, the kind already done on western grids, to reduce load when the weather calls for a bunch of clouds, or uncorrelated energy production (e.g. wind, which won't necessarily go down on the odd cloudy day, or for on-grid cases just transmission lines to solar somewhere else, or a backup generator), pushes that much further to 100%.
Seasonal energy storage is uninteresting, you just overbuild the energy production instead. This is already done for every existing type of energy production to account for seasonal variation in demand.
If batteries became cheap enough where you could do days instead of hours affordably it pushes this sort of calculus into less sunny places as well, and there's every reason to think that they will become that cheap (perhaps not cheap enough to make weeks reasonable though).
> Seasonal energy storage is uninteresting, you just overbuild the energy production instead. This is already done for every existing type of energy production to account for seasonal variation in demand.
It’s the only thing that is interesting, considering you just hand-wove that last 3% of reliability away with vague “backup generators” and “transmission lines to other places”. Both immensely expensive items if they are idle 97% of the time.
I’m not interested in the least about having my grid availability at 97% - in a cherry picked location ideal for solar.
I’m totally fine overbuilding nameplate capacity for my solar field - already plan to by about 8x due to where I live. Panels are cheap! At least that problem seems more or less solved.
The issue is I have no realistic means to store that energy for even days much less weeks when the sun doesn’t shine. A small wind turbine can help a bit, but doesn’t get rid of the need for a backup generator.
The same holds true at grid scale currently - which is both a more important topic and more interesting to discuss than some rich tech bro being able to brute force his off-grid solar+battery install.
Someone needs to back that last 3% with something like a combined cycle natural gas plant. That amount of capital investment sitting idle is exceedingly expensive. The only thing you are saving much money on vs. running it all-out is fuel costs - you still need to staff it.
A national grid sounds pretty neat, but would both be crazy expensive and is so politically untenable that I don’t expect to see it seriously even discussed in my lifetime. Just a small amount of time spent in the rural areas of the country made me realize how utterly impossible it would be due to NIMBY.
Again, to me at least that last 3% is where everyone hand-waves and makes it someone else’s problem. At some point though you run out of other people’s power.
I do wish we had not destroyed our nuclear industry into irrelevance, as 50 more years of experience and hands-on construction knowledge pushing that tech forward might have had us in a far different place today!
And fwiw I do hope I’m wrong. Perhaps energy storage gets to the point we can keep a fully reliable inexpensive grid for the common folks and industry to rely upon. I’ve certainly been wrong before!
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