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Also true for California for quite some time.
https://www.canarymedia.com/articles/solar/california-solar-...
What's going to happen in the future is that May will be a month of extreme electricity abundance, with a good chunk of the electricity just not being collected at all because the grid doesn't need it, and it will be cheaper to have unused electricity in May than to have too little solar in December.
And eventually that arbitrage will be big enough to justify a pumped hydro/gravity/iron-air storage.
Pumped storage utility is tied to duty cycle.
You want one cycle per day with some overage, not one cycle per year.
A lot of the cost scales with storage volume.
If you look at the pumped storage projects built and under construction in China, they are all daily focused.
To play devil's advocate: there are also some limited opportunities to retrofit large reservoirs with some amount of back-pump, when there's a sufficient reservoir at the bottom site. Not a ton, but a bit. However even those opportunities, that already have massive dams, may not be economically feasible because solar panels are just so damn cheap.
Solar's zero marginal cost generation, with cheap capital costs, requires rethinking a lot of the economics of electricity generation. Not paying for fuel changes so much, and it will take a while for people to internalize this.
Doubtful, the tradeoff is solar cost versus storage cost. Pumped hydro and gravity are waaaaaaaay too expensive compared to excess solar panels. Pumped hydro takes massive construction projects, which are very very expensive these days. Gravity storage (non-water, meaning non-hydro) never made any sense at all, the material costs are just way too high.
Iron-air storage is still being proven out, but it still requires so much material that only getting 1-2 cycles per year just won't justify it, because electricity is going to be so cheap.
It's hard to overstate how cheap solar panels are these days. Even in the US, which has costs 3x-5x the rest of the world because of failed protective tariffs.
>Doubtful, the tradeoff is solar cost versus storage cost.
The arbitrage is solar cost vs storage cost vs other energy source cost vs capital cost vs transmission cost.
Appropriately priced risk with all of those factors in and what you get out is solar+storage capping the price of other energy sources.
Lithium is the way, almost as cheap as sodium for a superior capability profile. Like solar, it just got cheap enough incredibly fast.
https://pv-magazine-usa.com/2026/07/27/global-battery-storag...
https://www.spglobal.com/energy/en/news-research/latest-news...
https://ember-energy.org/latest-insights/global-electricity-...
Large-scale battery storage is already expanding rapidly, and is way cheaper than pumped storage.
pumped storage is still significantly cheaper for seasonal storage. The cut off is about 2 weeks now -- if you need to pull from storage more than twice a month batteries are cheaper. If you need to pull from storage less than twice a month pumped storage is cheaper.
Or possibly the return of some heavy industry?
I always wondered that - but will it be economical to have the plants not working in the months of the year that the energy isn't free?
Maybe. Depends on the plant. Nearly every plant goes through shutdowns for maintenance. If energy is a large cost they work with the utility (and vice versa - when the utility needs to shut down a big power plant they need industry to shutdown something at the same time). Many of them take December off for maintenance. My company has long pour iron in the foundry only at night: we get enough of a discount on power as to be worth paying the workers extra to work the night shift (I last checked this 15 years ago - I would not be surprised if this has changed now that the local power is mostly wind and thus has different factors)
Of course every plant is different. There is a big difference between "batch" processes where you can shutdown after any batch, and "continuous" processes where startup/shutdown is a large process since the machines depend on running. They have different abilities to respond. Some plants/processes use more energy than others - obviously if they don't use much energy they don't care about free energy much either. The more energy a plant uses the more they are interested in cheap energy. In some cases a less efficient process may suddenly become better when solar is "free"
It's not "will it" it's just a series of balances, capital costs vs energy costs.
If there's enough free energy and automation there gets to be a point where there will be people will start to disregard the capital costs as well and run 0ish input cost businesses with a vertical stack of stuff that they produced with 0ish input cost.
I think the challenges for heavy industry aren't as much the cost of energy, as it is the capital cost, and a workforce that has lots of options for higher paying jobs.
Heavy industries are usually pretty low on the value chain in economies. They do not provide much return on capital, compared to the high tech options and service options that are available in the US, but not available anywhere else in the world.
The rest of the (non-European) world dreams of the economic opportunities that are possible in the US, from Silicon Valley tech, to biotech, to the financial opportunities. China has been trying to climb up the value chain ladder for decades, and is slowly getting there.
It's mystifying to me why people are fantasizing about climbing down the value chain in the US, to being poorer, and allocating capital to things with lower return on investment. I just don't get it! What's the appeal?
Well, manufacturing capacity was the basis of US military dominance, which was the underpinning of the post WW2 US-led world order. That's pretty clearly eroded, and we're not sure we could win in a war against China, especially not a full-on war of attrition, and they're not sure about that either, and so they're steadily getting more willing to throw their weight around geopolitically, trying to get a setup that's more favorable to them. The difference in shipbuilding capacity is staggering, for example. Even if each of our ships had a 10-1 kill ratio, we'd still run out of ships first.
My read on why we want it back, anyway. I'm sure there are other reasons, too.
Except the water is in short supply, so where's that magically coming from? The Great Salt Lake is shrinking and specific to Utah. Just look at Lake Meade and Hoover Dam as an example.
The water requirements for pumped hydro for seasonal storage is a lot less than for generation.
- pumped hydro reuses the water in a loop rather than sending it downstream like generation
- pumped hydro only needs to produce power a few times a year rather than 24/7/365 like generation.
moreover, If you built a pumped storage facility on lake Meade, it would have greater height and power from release the lower the lake was
> What's going to happen in the future is that May will be a month of extreme electricity abundance, with a good chunk of the electricity just not being collected at all because the grid doesn't need it
This is already a thing in some places. Or, sometimes, because the grid can't _take_ it. Here's a dashboard for Irish energy production: https://www.smartgriddashboard.com/all/solar/?duration=month - on the wind and solar you'll notice that on big days, actual production is usually way below forecast production. This is sometimes due to actual mis-forecast, or due to renewable production being high enough that it meets total demand. But usually it's that the _grid_ can't take it; there is demand, but no way to get it there.
It's a chicken-egg problem, of course; you're not going to build excess grid capacity in the hopes that someone one day builds a wind farm, so in practice grid upgrades trail renewable sources.
If only we could use that extra power to make methane for later power plant useage
The idea has been around for decades: https://en.wikipedia.org/wiki/Power-to-gas
The obstacle for this process (and in synthetic hydrocarbon fuels more generally) is obtaining the carbon dioxide efficiently. Atmospheric carbon dioxide is in too low of a concentration to be viable. You could source the carbon from coal, but that makes it no longer carbon neutral.
Prometheus fuels is one of several startups pursuing this kind of technology. But it's still blocked on effective air capture of carbon dioxide.
While the energy used couldn't be recovered, desalinating water for later would be a good use for California, given how the climate is going to go. Not that desalination plants exist for free.
Not the future, now.
Most Australians now get free power for three hours a day because there is simply so much.
This is the way.
Solar harvest time.
Make ray while the sun's shinin'
Vaclav Smil would be quick to replace the word power with electricity in the title of this article. It is why Germany can say renewables supply 56% of its electricity while renewables supply only about 21% of its energy. The rest of energy generation won't quickly be replaced with renewables: diesel and kerosene moving freight and people, natural gas in furnaces and boilers, coke reducing iron ore into steel, methane feeding the reactors that fix nitrogen to make fertilizer, and coal that turns limestone into cement.
I am fully on board with renewables! I have just found Smil's perspective quite useful here.
You've learned well from Smil how to make problems seem insurmountable by intentionally not approaching them with an engineering mindset.
We know how to do 80% of electricity, 80% of low temp hearing, 80% of transport all while saving money, reducing local pollution and delivering better products.
The big problem isnt technical,it's the culture war that Smil is fighting on the wrong side of and which spreads lies about renewables, EVs and heat pumps.
Vaclav Smil has been so wrong on energy, that I'm a bit surprised to see his name mentioned at all.
The idea of "primary energy" versus electricity is an important concept, but completely unconnected to Smil.
Sad to see coal going up (?)
The chart defaults to ending at 2025. Move the right timeline marker all the way to the right (today).
> In 2025, coal composes just 15 percent of U.S. electricity generation, and while 190 gigawatts (GW) of coal capacity remain online, the fleet is down 43 percent from 340 GW at its peak in 2010. This change is largely due to the fact that coal power is simply more expensive than cleaner power sources like wind, solar, batteries, and natural gas.
> Electricity demand growth and new actions by the current U.S. presidential administration may slow this decline in the short-term, but with no proposals to build new coal plants anywhere in America and worsening economic competitiveness – particularly where policymakers are strengthening air and water standards to protect their constituents – its long-term share of U.S. electricity generation will continue to decrease
https://energyinnovation.org/expert-voice/what-is-coals-futu...
Paid article by solar-energy lobbyist.
good thing the President is pouring billions into restarting coal plants
what a freaking horror show we are living in
At least at this point solar can be driven by pure market forces, it doesn't need federal subsidies to make sense.
It's unfortunately worse than coal subsidies. There are direct Federal orders that obsolete coal plants are not allowed to shut down. One example from Washington state:
https://www.opb.org/article/2026/06/18/federal-order-keeps-w...
There is open, and there is operating. This plant hasn't produced power in a while, but if someone wants to it is still open and so you just need to fire up the boilers again. The order just keeps it available to start again, it doesn't force it to burn coal. Closing the plant means they don't have to do maintenance, and perhaps they will tear it down.
While the politicization of renewable energy isn't great, the interesting and positive thing to me is that it's entirely possible we're past the tipping point where the politics really matter.
Republican politicians in the US publicly rail against renewable energy because it's red meat for the Fox News crowd, but in reality you see even very Republican states like Utah investing in renewables because economic reality ultimately beats political ideology on stuff like this.
Maybe the worst aspect of renewable energy being turned into yet another political culture war issue is that while renewable energy resources themselves are probably inevitable, the political nonsense surrounding them has helped limit US investment in their development relative to places like China. As a result, the US and the West as a whole is likely to be far more reliant on Chinese technology in renewables than we otherwise might have been.
Utah isn't a power grid.
They're on the western interconnect.
Combined solar and wind are about 25-30% of production there.
These articles about individual states are trash.
Fwiw I think Utah is the only state with legalized plugin solar (many more on the way though!)
A few more states have recently joined it.
https://pluginsolarus.com/states
State plug in solar legislation tracker: https://www.brightsaver.org/legislation-tracker
(passed in 10 states, 2 awaiting signatures, as of this comment)
Utah is about half of the Pacificorp East balancing authority.
https://app.electricitymaps.com/map/zone/US-NW-PACE/live/fif...
Nevada Power serves a substantial amount of western Utah.
https://app.electricitymaps.com/map/zone/US-NW-NEVP/live/fif...
Cool, that's still not a grid for stability purposes.
https://www.eia.gov/tools/glossary/index.php?id=Balancing%20...
> Balancing authority (electric): The responsible entity that integrates resource plans ahead of time, maintains load-interchange-generation balance within a Balancing Authority Area, and supports Interconnection frequency in real time.
https://www.nerc.com/glossary-of-terms
> Definition & Scope: A BA is a NERC-certified entity responsible for matching electricity supply and demand in real-time within a specific geographic area. An ISO is an independent, non-profit corporate entity that manages regional transmission grids and runs competitive wholesale power markets.
https://www.ferc.gov/electric-power-markets
A balancing authority is quite literally a federally certified entity for maintaining grid stability.
(Utah only has ~2.5GW of coal generation capacity remaining, as of this comment)
https://www.gem.wiki/Utah_and_coal#Existing_coal_plants
https://www.gem.wiki/Utah_and_coal
https://utahnewsdispatch.com/2025/12/05/intermountain-power-...
can you expand? I'm not sure I get it. isn't then having a wider interconnection better for stability and to handle solar? they can share cheap power in gluts and pull in other sources at night and so on.
I think I know what this means, but I bet you share a better explanation with us all too of the point you're making
Okay debbie downer, it's still positive news
So? We can still measure how much power everyone in a state uses, and how much power the state generates. Utah generates a lot of power from non-renewable sources, and I assume (but I can't find data) they have the ability to generate a lot more but didn't because solar was used instead. That solar is a big part of what Utah generates is just big news.
Now if we are comparing a hypothetical place that doesn't have anything else this wouldn't be interesting, but that isn't the case. (I'm sure my suburb generates more energy from solar than anything else - as you would expect the only other generation we have is backup generators)