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190 points erwinmatijsen | 12 comments | | HN request time: 0.001s | source | bottom
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arowthway ◴[] No.45113659[source]
This is super cool but the ending is bizarre.

> A comment on the YouTube video below complained, “Not a word about return on investment in the presentation. That means it’ll never pay off” MAGAlomaniacs are everywhere these days.

Given the supposed 50+ year lifespan of such a battery, I find it hard to believe it doesn't turn a profit at some point. And I understand that debunking low-effort accusations is asymmetric warfare. But why cite a random YouTube comment if you have no intention of addressing its claims? A more charitable interpretation is that it's meant to ragebait the readers. But to me, it seems like trying to make people feel ashamed for having doubts, by making a public example of a skeptic.

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kragen ◴[] No.45114440[source]
If, say, further insulating your house or building a sand battery will pay for itself in 50 years, it's a bad investment, financially speaking, and probably environmentally speaking as well. You can deploy "the same amount" of resources in something else with a higher ROI, like maybe solar panels with a one-year payback, and get a much bigger benefit. This is an important consideration as long as you are constrained by some kind of resource limitation.

So I think ROI is a first-order consideration.

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bryanlarsen ◴[] No.45114692[source]
Finland is the only country in the world where solar isn't the cheapest form of electricity because they get so little sun and they have good alternatives.
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hulium ◴[] No.45115007[source]
Certainly not the only country. Iceland is even more extreme in this regard and unlike Finland it is powered by 100% renewables, hydro and geothermal energy. In Finland the only good renewable alternative is wood/biomass.
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1. bryanlarsen ◴[] No.45115386[source]
Seems reasonable. I'll have to dig up my source to double check. Maybe they just didn't have Iceland data in their set? It's certainly a surprising result to see other non-sunny places like the UK, Germany, Norway & Sweden have solar as their cheapest energy source.
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2. kragen ◴[] No.45116514[source]
It's hard to get really solid estimates for solar costs because they've been dropping so precipitously, and because they depend on so many ancillary factors: wiring, inspections, permitting, power electronics, storage, and so on. Getting solid estimates for solar return on investment is even harder, because it depends on the future price of energy.
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3. bryanlarsen ◴[] No.45116801[source]
Yes, it's certainly possible that Iceland is better for solar than Finland not because of its sunlight, but because of those myriad extra factors.
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4. ponector ◴[] No.45119996{3}[source]
I'm sure there is no sense in solar energy in Iceland due to strong winds there as well as geothermal energy.

It's sad they are building gas-powered data centers in US instead of powered by renewables in Iceland.

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5. kragen ◴[] No.45120814{4}[source]
Windmills can be surprisingly expensive. https://www.eia.gov/analysis/studies/powerplants/capitalcost... is not up-to-date, but I think the windmill prices in it have changed a lot less than the solar prices; the 200 MW onshore project they price out there comes to US$1265/kW (US$1.27/W), of which something like 61% is the windmills themselves. Low-cost photovoltaic solar modules currently cost €0.055/W (US$0.065/W), lower by more than an order of magnitude https://www.solarserver.de/photovoltaik-preis-pv-modul-preis....

So, at equal cost, the alternative to a megawatt of windmills may not be a megawatt of solar panels, but 10 megawatts of solar panels. And that can compensate for their lower capacity factor.

I don't think people are building gas-powered data centers in the US. There's a data center crunch in the US because people aren't building them because they can't get the power because of the US's anti-renewable-energy policies.

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6. ponector ◴[] No.45130551{5}[source]
Difference is massive, but price of land should be also accounted for. Solar uses 5 times more land per MW.

The solution is to develop everything, all kinds of renewables.

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7. bryanlarsen ◴[] No.45130758{6}[source]
You can buy land in the desert for under $1000 an acre. There are places you can buy farmland for under $10000 an acre.
8. kragen ◴[] No.45131068{6}[source]
Even the EIA-commissioned study I linked doesn't include that, but it is a potentially significant cost. If we take the median price of US$4702 per Texas "acre" from https://texasfarmcredit.com/resources/texas-land-pricing-gui... it works out to US$1.16/m². At 30° latitude your panels provide about 0.86 square meters of panel per square meter of land, or more like 0.3 with trackers, so the land price is on the order of US$3/m². A square meter is nominally a kilowatt of sunlight, so that's US$0.003/W of sunlight, but mainstream panels are usually only around 21% efficient, so it's more like US$0.015/Wp. Historically this has been insignificant but may no longer be with mainstream panels costing only US$0.10/Wp.

Desert land, lakes, and harbors are cheaper, so we should expect to see more panels there instead of on potentially arable land.

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9. hulium ◴[] No.45132297{3}[source]
I think Finland just has a large enough extent from south to north that solar might be starting to become viable in the south but not in the north. While Iceland already produces more electricity per capita than any other country, using only hydro and geothermal, so solar is pretty much non-existent.

Comparison of solar share:

https://ourworldindata.org/grapher/solar-share-energy?tab=li...

Solar potential:

https://en.wikipedia.org/wiki/Energy_in_Iceland#/media/File:...

10. kragen ◴[] No.45132719{7}[source]
Sorry, that's Texas farmland "acres". An "acre" is a medieval unit of measure defined as one "chain" by one "furlong", the area a single man can plow in a day with a team of oxen. Although people have been plowing with horses since the 12th century, the "acre" is still in use in Texas, where it is roughly equivalent to 0.405 hectares (4050m² in SI units). In Texas, latitude ≈30°, it amounts to roughly a megawatt of solar energy (3 megawatts peak) before accounting for panel inefficiency.

Also when I said "US$0.10/Wp" I was wrong. I'm in the lazy habit of rounding US$1 = €1, but that's a significant error now. The correct price of €0.100/Wp for mainstream solar modules is more accurately US$0.117/Wp.

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11. CRConrad ◴[] No.45138314{8}[source]
> An "acre" is a medieval unit of measure defined as one "chain" by one "furlong", the area a single man can plow in a day with a team of oxen. Although people have been plowing with horses since the 12th century, the "acre" is still in use in Texas...

1) People plowed with oxen well into the 20th century. Most places, only fancy people could afford horses at least into the 17th-18th century. So not so totally-medieval.

2) The acre is used in all kinds of backwards (Anglophone) places, not only Texas. All of the USA for starters, probably Australia, maybe the UK... Heck, I remember my elders using the (roughly) corresponding "tunnland" in daily conversation in Sweden as late as the 1970s. (But yeah, they were really rather elderly.)

3) Aren't you the guy who should call that "the 0012th century"? (Sorry if I'm getting you mixed up with someone else.)

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12. kragen ◴[] No.45138770{9}[source]
Agreed on all points! (Except "should".)