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Finnish City Inaugurates 1 MW/100 MWh Sand Battery

cleantechnica.com

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Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#171

Post by fulafel »

Ekaros wrote: post #143
fulafel wrote: post #141

Earlier quoted context omitted.

I think it's more like 90C in (winter), 40C out. The temps have been going down in newer infrastructure as it's more energy efficient. See eg https://www.shcbysweden.se/wp-content/uploads/2019/11/Best-P... p. 7 And of course it's still a win if you can heat the return water half of the way to spec with the battery, it's not necessary to have the battery heat it all the way to the plant outgoing temp. District heating…

Other limitation that I know is that for tap water minimum is 55C. So the last building in loop should get at least that much. So 40C is only acceptable back at power plant. In the end it comes to balance with cost, simplicity, capacity and such. Heat pumps do allow extracting heat from colder storage medium. But on other hand electric heating elements and heat exchangers are very much simpler and cheaper.

In the good systems there's two pipes, return gets its own (like eg the earlier linked PDF describes), so it's fine for buildings to output cooler water to the return pipe.

But yes heat pumps are used in some parts as well in DH.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#172

Post by ta1243 »

hliyan wrote: post #118
Avamander wrote: post #68

Earlier quoted context omitted.

> Majority of people and countries in the world do not deem ROI to be the sole or even primary driver for investment It's partially that, other part is that we aren't really pricing in all the externalities of everything out there. So it's not that "there's no ROI", it's that "we aren't factoring things in the ROI calculation". So while a heat battery might not make a huge profit, the ability to burn less fuel (less…

Externalities can (and should) be priced in by taxes that offest negative externalities (e.g. carbon emissions, pollution). Unfortunately, legislative bodies that have to decide on taxes have a much cozier relationship with industry than they do with those who must endure the effects of negative externalities (the general population).

Put a carbon tax on fuel in a western country and you end up with an unhappy population who pay more money in tax. Personally I'd distribute the revenue as a UBI which would mean the most polluting would be worse off but the average person would be better off.

The people who would mostly benefit from reduction in emissions - especially in the short term - are those in other countries. It's not going to be Finland suffering the most from doubling of the cost of food from failed harvests, it's going to be massive failures in rice harvests in south east asia. Finns will always be able to outcompete the average Cambodian when buying food.

One of the costs of emissions to western countries - say Spain - is increased bad weather - more frequent storms, fires etc. All fairly small stuff compared with mass starvation or water shortages though. That starvation leads to another problem -- increased migration pressure.

But those costs are going to be borne anyway. Even if Spain stopped emitting CO2, it wouldn't make an ounce of difference. International agreements have failed time after time to curb emissions.

The main benefit of renewable energy for a given country isn't the reduction in emissions, it's the increase in energy independence - no need to import gas or oil from unstable countries.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#173

Post by ta1243 »

zahlman wrote: post #115
ta1243 wrote: post #109

Earlier quoted context omitted.

> There are 10% opportunities in most people's lives Average S&P total return (reinvesting dividends) is well over 10% over any appreciable timeframe (say 30 years), even during really low times (say buying at the peaks in 1999 or 1972)

The long term average is a bit over 10%, but there are definitely 30-year periods that have fared worse than that.

Which specific 30 year period?

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#174

Post by fulafel »

bryanlarsen wrote: post #114
kragen wrote: post #96

Earlier quoted context omitted.

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…

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.

You could be forgiven to think that about northern places, but the dark winters are compensated by the long (or even round the clock) daylight in summer. It's still fewer sunlight hours than markedly sunny places like italy or california but not 50% less.

see eg this map where scandinavia is the same color as france or southern uk: https://vividmaps.com/annual-sunshine-hours-of-world/

But of course wind is more stable around the year and produces more in the winter when there's more need for energy. And the sunlight is more direct closer to the equator.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#175

Post by bryanlarsen »

fulafel wrote: post #174
bryanlarsen wrote: post #114

Earlier quoted context omitted.

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.

You could be forgiven to think that about northern places, but the dark winters are compensated by the long (or even round the clock) daylight in summer. It's still fewer sunlight hours than markedly sunny places like italy or california but not 50% less. see eg this map where scandinavia is the same color as france or southern uk: https://vividmaps.com/annual-sunshine-hours-of-world/ But of course wind is more stabl…

I didn't just think that, I read it in a news article about a study. My memory of what I read may be faulty, though.

Besides fewer sunlight hours, Finland also has lots of clouds and very steep sun angles which significantly affects production.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#177

Post by fulafel »

bryanlarsen wrote: post #175
fulafel wrote: post #174

Earlier quoted context omitted.

You could be forgiven to think that about northern places, but the dark winters are compensated by the long (or even round the clock) daylight in summer. It's still fewer sunlight hours than markedly sunny places like italy or california but not 50% less. see eg this map where scandinavia is the same color as france or southern uk: https://vividmaps.com/annual-sunshine-hours-of-world/ But of course wind is more stabl…

I didn't just think that, I read it in a news article about a study. My memory of what I read may be faulty, though. Besides fewer sunlight hours, Finland also has lots of clouds and very steep sun angles which significantly affects production.

The cloudiness is accounted for in the visualization, otherwise you wouldn't see that much variation on the same latitudes. But yep the sun angle affects things too like I mentioned.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#178

Post by ponector »

kragen wrote: post #167
ponector wrote: post #164

Earlier quoted context omitted.

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.

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),…

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.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#179

Post by bryanlarsen »

ponector wrote: post #178
kragen wrote: post #167

Earlier quoted context omitted.

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),…

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.

You can buy land in the desert for under $1000 an acre. There are places you can buy farmland for under $10000 an acre.

Re: Finnish City Inaugurates 1 MW/100 MWh Sand Battery

#180

Post by kragen »

ponector wrote: post #178
kragen wrote: post #167

Earlier quoted context omitted.

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),…

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.

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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