←back to thread

Solar Is Cheapest Electricity in History, U.S. DOE Aims to Cut Costs 60% by 2030

(cleantechnica.com)
131 points mg | 5 comments | 26 Mar 21 20:07 UTC | HN request time: 1.21s | source
Show context
rich_sasha ◴[26 Mar 21 22:13 UTC] No.26597628[source]▶
If solar were free, but we still needed to pay for battery storage, how would it then compare in cost to fuel-based alternatives (fossil fuel, nuclear etc)?
replies(6): >>26597661 #>>26597691 #>>26597763 #>>26597783 #>>26597850 #>>26598615 #
kleton ◴[26 Mar 21 22:19 UTC] No.26597691[source]▶
Would need $20/KWh battery storage to be competitive with nuclear for baseload according to https://www.cell.com/joule/fulltext/S2542-4351(19)30300-9 At the moment, we're at about $800/KWh.
replies(3): >>26597895 #>>26597898 #>>26598636 #
jxidjhdhdhdhfhf ◴[26 Mar 21 22:44 UTC] No.26597895[source]▶
Aren't car battery packs under $100/KWh? Is there some other factor which drives up the price for grid level storage?
replies(1): >>26598247 #
manfredo ◴[26 Mar 21 23:30 UTC] No.26598247[source]▶
The factor that drives up price for grid level storage is scale. Only ~300 GWh worth of batteries is produced globally each year. The world uses 2.5 TWh of electricity each hour. If anyone tries to install battery storage at a significant scale, demand will vastly outstrip supply and drive prices up.
replies(3): >>26598258 #>>26598590 #>>26599059 #
jeremysalwen ◴[27 Mar 21 00:26 UTC] No.26598590[source]▶
Assuming there aren't economies of scale. Demand for solar had gone way up in recent decades (e.g. in germany, before it was cheap), and the price subsequently went down.
replies(1): >>26598675 #
mlyle ◴[27 Mar 21 00:38 UTC] No.26598675[source]▶
It's not clear batteries will do the same. While there's been effort to make batteries less reliant on scarce natural resources and mining, there's no guarantee we really get there. If we don't, price can be expected to go up, not down, with scale.

I would bet on price going down slightly with scale, but one can't really tell now what will happen: it might go up a lot, it might go down a lot, or it might stay flat.

replies(1): >>26598795 #
pfdietz ◴[27 Mar 21 00:56 UTC] No.26598795[source]▶
There are thousands of different chemistries for batteries. The nuclear stans are betting that all of them fail.
replies(2): >>26598835 #>>26609326 #
Manfredo_1 ◴[27 Mar 21 01:02 UTC] No.26598835[source]▶
None of those other battery chemistries are seeing the massive growth that lithium ion batteries have experienced. The nuclear "stans" are just pointing out that these are potential solutions, not actual solutions. If iron oxide batteries, or some other chemistry, suddenly becomes cheap and easily deployed at the TWh scale, great. But until then they're not a solution.
replies(2): >>26598857 #>>26609329 #
pfdietz ◴[27 Mar 21 01:04 UTC] No.26598857[source]▶
Yes, you all are engaging in the "nothing can be invented" argument. It's profoundly reactionary, and also hypocritical, because nuclear itself is dead without great improvement. Uranium quickly runs out if the world is powered by burner reactors and known uranium resources, so either massive seawater uranium extraction or breeding cycles would be needed.

Batteries have the advantage of being explorable at a small scale. Now that the potential market has become so clear this is happening, in many companies.

replies(2): >>26598943 #>>26599219 #
mlyle ◴[27 Mar 21 02:07 UTC] No.26599219[source]▶
> Yes, you all are engaging in the "nothing can be invented" argument.

No, we're engaging in the "this has been resistant to being invented so far, so let's not bet everything on it showing up tomorrow" argument.

> Uranium quickly runs out if the world is powered by burner reactors and known uranium resources

You could quadruple the present rate of uranium use, representing in a major contribution to mankind's energy use, and have 35 years of supply, just using known reserves and no breeding.

And if you were using that much uranium, more reserves would be quickly proven. Do you think we've found all the uranium we'll ever find, even if market prices go up significantly?

And breeding is possible, and understood. Yes, there's proliferation concerns, but that's not the end of the world.

And seawater extraction is practical without much increase in cost.

No one is saying "no renewables" or "no battery storage" or "no pumped storage". Or "no power to gas to power". We need all of these things. And we need the diversity of having nuclear in the mix, too.

replies(1): >>26599346 #
pfdietz ◴[27 Mar 21 02:29 UTC] No.26599346[source]▶
Not at all. The technology for hydrogen energy storage is (with the possible exception of cheap electrolysers) is off the shelf. It's not widely used not because it's not available, but because natural gas is cheaper to store and burn when there are no CO2 taxes. But the CO2 taxes will be raised enough to push natural gas out, if we're going to control global warming.
replies(1): >>26599602 #
mlyle ◴[27 Mar 21 03:16 UTC] No.26599602[source]▶
When the largest electrolyzer we have in the world is 10MW... and hydrogen storage hasn't been demonstrated at anywhere near the scale you're talking about... it's a tad of a stretch to talk about it being "off the shelf." Particularly when you point to nuclear fuel reprocessing and breeding as nonexistent in the same thread.
replies(1): >>26599626 #
1. pfdietz ◴[27 Mar 21 03:20 UTC] No.26599626[source]▶
We can run electrolysers in parallel to scale to any desired output level. There might be economies of scale to make them even larger, or there could be economies of manufacturing scale of making smaller ones at higher volume. PV and wind are examples of technologies that work well with large numbers of not so large units, replicated as needed. This is a nice place for a technology to be.
replies(1): >>26599674 #
2. mlyle ◴[27 Mar 21 03:30 UTC] No.26599674[source]▶
A few prototype / demonstration units at 10MW scale and lower is not proven, off the shelf technology. Fullstop.
replies(1): >>26605094 #
3. philipkglass ◴[27 Mar 21 19:58 UTC] No.26605094[source]▶
Electrolytic hydrogen plants of up to 250 MW were constructed in the 20th century by the use of smaller electrolysis units in parallel. All of them were for producing ammonia from hydrogen. See table 3-2 on page 99 of this NASA report from 1975:

"Survey of Hydrogen Production and Utilization Methods"

https://ntrs.nasa.gov/api/citations/19760008503/downloads/19...

250 MW, Rjakon, Norway, built 1965

170 MW, Kima, Egypt, built 1960

125 MW, Nangal, India, built 1958

90 MW, Trail, Canada, built 1939

25 MW, Curco, Peru, built 1958

replies(1): >>26606325 #
4. mlyle ◴[27 Mar 21 22:49 UTC] No.26606325{3}[source]▶
??? Those are input powers of terrifically inefficient and expensive electrolyzers. That 250MW plant put out 17MW of hydrogen -- (120 (megajoules / kilogram)) * ((0.000236 kilograms) / (cubic foot)) * (2 200 000 ((cubic feet) / hour)) = 17,306,667 Watts.
replies(1): >>26606861 #
5. philipkglass ◴[28 Mar 21 00:11 UTC] No.26606861{4}[source]▶
I think that you slipped a decimal point. The mass of a cubic foot of hydrogen is about 0.00236 kg, not 0.000236 [1]. That means that the output power is an order of magnitude greater than you calculated -- 173 megawatts.

[1] https://microsites.airproducts.com/gasfacts/hydrogen.html