> Solar is cool but solar that can make it through the night and a couple cloudy days is way cooler
The fun part is that we're still well before the point when this even matters.
Almost 60% of the US grid is still fossil fuels, with around half of that still happening during the day. Which means you can get down to ~30% fossil fuels without any storage at all because all you do is go from burning fossil fuels during the day and at night to burning fossil fuels only at night.
> at night to burning fossil fuels only at night
only natural gas plants can do this. a coal plant cannot spin up just for the night and turn back off when the sun comes up - it's incredibly inefficient and probably causes more premature wear/tear too.
Full startup and shutdown of a coal plant can take days, but throttling down to about half power during low-load periods is normal. Power plants do this every day. Late at night, load decreases and plants throttle down. Every morning, between 0600 and 0900 local time, there's "morning load take-up" as load increases.
The big issue is what's called "ramp rate" - how fast can output power be increased or decreased? This tends to be around 1% to 3% of capacity per minute. See Figure B-2 in [1], which is a detailed discussion of how to improve your coal-fired power plant's ramp rate.
Natural gas plants have much higher ramp rates, and for batteries, it's under a second. Nuclear plants can be ramped up and down, slowly, but since it's all capital cost, cutting output raises the price of the power.
[1] https://www.epri.com/research/products/3002012979
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"Increased rates of component life consumption due to thermal fatigue, mechanical fatigue and wear caused by differential thermal expansion comprise the bulking of cycling (costs)," according to the International Energy Agency's Coal Industry Advisory Board.
"Every time a power plant is turned on and off, the boiler, steam lines, turbine and auxiliary components go through unavoidably large thermal and pressure stresses," the National Renewable Energy Laboratory (NREL) wrote in a report on cycling costs published in April 2012.
"
https://www.reuters.com/article/business/energy/to-survive-c...
Yep, I live in Finland where we are quite far ahead of the curve when it comes to renewables and nuclear. This is one large problem. When it's winter and cold and dark, solar does not help. Wind only helps when its windy.
Batteries are coming, and will solve it, but it will still take time for them to be come cheap enough.
Only once we have ~7 days of storage (~100 GWh of storage) will we be able to get rid of the last fossil plants.
Yeah the US will lag behind on this.
Other countries are better positioned. e.g. UK has really spiky wind energy. Right this second more than half the grid is wind. Which is both cool and problematic for managing the grid.
Grid scale cheap storage would dramatic help manage that chaos
Other countries are better positioned already because they don't have an administration funded by the fossil fuel lobby - but even that doesn't explain some of the decisions, like preferring to reimburse $1 billion in already paid leases rather than letting a company build wind farms on the leased area (https://edition.cnn.com/2026/03/23/climate/trump-totalenergi...).
Spain suffered a black out partially due to the lack of momentum (spinning generators).
For Europe to get rid of more fossils without putting the grid at risk we will need more storage.
I surprised we can’t, or rather don’t, make more use of tidal energy.
That and low energy density storage located at sea with the turbines.
Hmm, how much of that is base load versus the dramatic rise of natural gas plants that respond to dynamic demands? Even in daytime, I think you need storage to get rid of those, right?
I don't know why this is downvoted. Solar and wind both essentially suck at anything other than baseline throughput. That doesn't mean they're useless, it just means that solar can't be our only solution unless we have, like... 30 breakthroughs tomorrow. We otherwise need something to handle spikes, which are both common and important, as well as periods when there is extended cloud cover even for typically-dark months.
Even if we handwave all the science needed to build batteries big enough to power cities for days, I don't think it's realistic to handwave the science needed to power a city for weeks. We don't even have enough oil for that.
"Power when it is inconvenient" is pretty much the basis for a modern society.
Solar panels still work just fine when it is cloudy, just with a lower output. And usually when it is cloudy it also tends to be a bit windy, so solar and wind nicely complement each other.
Heavy clouds and zero wind, for weeks? That's a once-a-century freak event. Just build gas peaker plants if you are worried about it. You could even add carbon capture, but constructing it might emit more than it will ever capture...
> Solar panels still work just fine when it is cloudy, just with a lower output.
I assume you never tried measuring the output of a solar panel when it's cloudy. It's 10-15% of a sunny day. Closer to not working than working.
Depends on the cloud. Where I live I routinely get 50% generation on a "cloudy" day.
On a rainy day that drops closer to 20%.
As an aside - cloudy days avoid a problem I have with shade. In winter, at 3:30pm, the sun goes behind a tree and my production plummets to near zero. If there's cloud cover the sunlight is far more dispersed and there's no "shade".
> On a rainy day that drops closer to 20%
And you’re still able to power your entire home? What if the rain lasts for a few days, which is pretty common in many places.
No, 20% is not sufficient to power the home. I'm still attached to the grid and use grid power even solar is too low.
Worst I've had over a day in the last few months on my home solar is about 25% of my maximum daily generation. It was one day in a very rainy week here in Brisbane Australia.
I did have one rainy day back in the middle of Winter that was 16% but that will end up being literally the worst day of the year.
That's every single winter where I live in the US. We don't have a word for it like the Germans do, though, we just call it January.
The good news is: you're on a national (or semi-national) grid, and conditions like that are more unusual than they are common across the USA.
You want us to transport energy 1500 miles? Cold, dark winters cover enormous swathes of the US - inconveniently, often at similar times. So what - we're turning Florida into a solar park so the rest of the nation can use that while they're dark?
Our energy grid can't currently handle the ability to charge electric haulers locally at any scale let alone to move an entire city's worth of energy, so the solution is not to 85x the national electric grid all at once.
I used to think the people who took this "America is too incompetent to make the green transition" stance were just downplaying the tech out of some combination of ignorance and weird partisan logic.
But to give them due credit, they believed in this vision and put in the hard work to make sure it became true.
> You want us to transport energy 1500 miles?
That's literally CCP state controlled communism !! More specifically, that's what the Gansu–Zhejiang UHVDC project has as an overhead transmission line length (2,370 km in international units).
* https://www.sciencedirect.com/science/article/pii/S014206152...
* https://www.bbc.com/future/article/20241113-will-chinas-ultr...
Carbon capture makes little sense until fossil fuels have been replaced. I guess there are some Bio char technologies that might change the equation a bit, but watt for watt, you need to replace your carbon emissions first (generally speaking)
A week of low solar and low wind is a yearly or every-couple of years event that you definitely need to solve for a completely renewable grid.
Keeping coal plants around is cheap to cover that. Longer term things like producing ammonia during summer and converting it to electricity in fuel cells will allow to remove needs for fossil fuels completely.
I’d keep gas plants around, but anyway, you need to cover that case and can’t just handwave it away.
The main advantage of gas plants is that they support variability. In a world with enough battery storage to last for days that would be irrelevant. And as an insurance against rare events it is better to keep coal plants as transportation and storage of coal is vastly more resilient to interruptions.
Strictly speaking - a battery is stored potential energy
A common battery for grid level storage is pumped hydro - that is, use the peak power during the day(s) to push water from the bottom of an elevation to the top, and hold it there - bonus points if it captures water delivered from other solar processes (evaporation -> rain)
There are about 90 billion battery solutions - none of them are very efficient, cheap to manufacture, easy to manufacture/acquire materials for, and long-lasting all at the same time.
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Typical non-informed incorrect opinion.
The overwhelming majority of generation and storage is best deployed at the point of use.
Grid scale anything, is a massive inefficiency.
The only reason grid and city scale is so prevalent in public discourse is because this is the only electricity the utility is paid for, and they are very actively impeding any other solution.
In the US, there is a very large inventory of flat roof industrial buildings, in the industrial parks that are using huge amounts of electricity. Covering all of those roofs with solar (especially here in the west US) would prevent a tremendous amount of grid scale generation, and implementing storage there would eliminate a large part of the transmission line upgrades the utilities are calling for.
The biggest problem in the US isn't technical, it's the governments desire to primarily support the solutions that are best at serving utility shareholder returns, instead of the technically superior solutions.
How common is it that these industrial/commercial buildings have roof-top solar? If not common, what stops it?
It's quite common in Australia for commercial and residential.
It doesnt make economic sense to serve the entirety of daytime electricity demand from solar without batteries. Youd have to tons of fossil fuel plants that turn off during the day and then back on every night. For solar to take the next step batteries are a requirement
It's not quite as bad as that, since you don't consume fossil fuel resources when plants aren't running, but this is mostly a benefit for oil/gas plants, not coal (since the coal is likely useless without the power plant consumer anyway)
Depending on the type of power plant, it can take quite a while to spin up (or down) one of them and get them to optimal power production.
https://www.eia.gov/todayinenergy/detail.php?id=45956
If you shut down by day, it can take multiple hours for it to be able to provide full load... and multiple hours for it to shut down cleanly. During this time it is producing power at less than optimal rates and/or using the fossil fuels to keep the wheels spinning and in sync with the grid so that they don't have to go through a phase matching period.
(aside for coal - note that it takes more than 12 hours for a coal plant to get running from a cold start)
That's not really a problem. A spin up over a couple hours matches nicely with the slow sunset over a continent. The sun takes ~4 hours to go from a bit above the horizon in the east coast to a bit below the horizon on the west coast (solar panels make some power in twilight).
Wind also helps since wind makes more power at night, as does demand which is dramatically lower at night.
For coal, Great. Making coal economical is excellent. We should have banned it worldwide 20 years ago.
USA should explore Pumped Storage Hydropower more, it has same or better efficiency than battery storage and can use existing facilities like hydroelectric dams
Part of the pumped storage problem is "where can you do it?"
There's a good number of 'em: https://en.wikipedia.org/wiki/Category:Pumped-storage_hydroe...
https://www.ferc.gov/media/licensed-pumped-storage-projects-...
You'll see that most of them are in the Appalachian mountains and in the Sierra mountain range.
The one in Missouri is one of the interesting ones that isn't in either.
https://en.wikipedia.org/wiki/Taum_Sauk_Hydroelectric_Power_...
> The Taum Sauk pumped storage plant is a power station in the St. Francois mountain region of Missouri, United States about 90 miles (140 km) south of St. Louis near Lesterville, Missouri, in Reynolds County.
It has a hydraulic head of 860 feet and that represents the challenge - you need to find places in the US where you can get several hundred feet of elevation in a short distance.
Hypothetically, lets build one in Minnesota... Taum Sauk Mountain is the highest point in Missouri. The highest point in Minnesota is Eagle Mountain (in the boundary waters - you can't build there, pretend we can) ... the elevation to the top os 550 feet (about half what Taum Sauk provides) over 3.5 miles (Taum Sauk is just over 1 mile). ( https://maps.app.goo.gl/vHfWarwubaLvsf5z7 )
Much of the US is too flat for it to be useful.
Solar+A couple of hours of batteries is already economically viable. The storage problem that is still expensive is bridging days/weeks of insufficient sun and wind.
The US uses around 4TWh of electricity a night. A battery with that capacity, to get through the night with no generation, would cost over a trillion dollars. Of course thered still be some generation at night, but still, using a battery just to get through the night is not even close to viable
You might want to update your numbers, 1 kwh is somewhere between 50€/kwh to 75 including electronics... No economics of scale, shipping included..
That makes 300B
Eu pricing
Just by scaling up the existing technologies the full cost including installation and maintenance of a grid-scale battery in 5 years will be below 100 usd/kwh. So the price is max 400 billions or 1% of US GDP.
The war in Iraq cost a trillion dollars.
So far.
Do you imply that it was really cheap, just like solar+batteries?
You generally get more return on investment if you invest in building infrastructure in your own country rather than investing in blowing up infrastructure in a different country. So I’m implying that solar and batteries are a lot cheaper than the war in Iraq.
1 week national battery storage is totally doable. All we need to do is convince the rest of the planet to stop making GPUs, phones, computers, and EVs for the next decade, and then give us all their rocks. 78.4TWh is about $19T (all in costs) for a national battery grid for 1 week storage, could be built over ten years but would need the US to build and own double the current global output, not even considering where all the raw materials and labor comes from.
Coal is a dead end anyway.
That might work in The SouthWest of the USA, but the Northern bits dont get enough sun to get through the day, so you'll need fossil fuel plants all day night for the Winter. If they're there already its cheaper to use all day in the summer as well.