Comment by AnthonyMouse
17 hours ago
> 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.
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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...
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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.
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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)
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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.
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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)
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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.