101–110 of 190 posts
Helsinki did the same thing but storing the energy in water instead of sand: https://helsinkismart.fi/worlds-largest-cavern-thermal-energ...
Collecting heat from wast water is free energy. When you defecate, wash clothes or dishes, or take shower there is warm water and solids going down the pipes. That heat can be used. In the summer stored cold sea water can provide district cooling.
Earlier quoted context omitted.
[flagged]
All those subjects in the right context are things the left wing fights for. Reducing a complex subject and then saying because you do not agree with my interpretation you are against children, is not optimal. E.g. Climate Activists are a pretty diverse group you will find lots of people who have said the same thing. It is obvious this is a PR/Research stunt, but it might still pay off. This is not a straight forward…
It seems to depend on having a network to distribute heat, which is something that you have to take into account... basically when you create your town ? Or is there a way to "retrofit" district heating into houses with their own gas boiler or heat pump ?
Good idea but why is it being measured in MW/MWh when it’s not an electrical battery? I know they can be converted but maybe it should be measured in actual thermal units like Btu?
Wh is an abomination that has come about because professionals think consumer brains would expose if they ever saw the unit watt-seconds (J). No consumer had any preconceived notion of either Wh or J, so had we used J from the start, it wouldn't have been a problem...
(Yes, same with Ah vs C, though the battery pros also shot themselves in the foot by starting to use C (electrical charge) to mean "the capacity of this battery" when talking about charge rate, a.k.a. current.)
Earlier quoted context omitted.
The higher temperature output is a good point, you can't get 400C output for industrial processes from a 100C water based heat battery.
a Blast furnace needs closer to 2000° than 400° in any case, how would you transport high temperatures to the industrial sites? water boils at 100° and few liquids boil above 400°. most liquids will be impractical due to cost or safety (combustibility, toxicity…).
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…
Surely the lifespan is almost forever. It's just a tank full of sand and some heating pipes. Maybe the pipes and/or control electronics needs to be replaced occasionally, but nothing should happen to the sand inside - like ever.
Earlier quoted context omitted.
People nowadays expect 10% return on their investment, so if you invest 1m you need to make 100k a year from it (120k to cover the deprecation over 50 years) If you made 30k a year for 50 years you'd return 1.5m from your 1m investment, but you're only making 3%, which is a low return especially given the future risk (you'd have to run for 33 years just to get your initial investment back) Either way it's worthwhile,…
> 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…
I think the more likely explanation is that this is a pilot project by a clean energy startup, it intentionally operates at a loss because it's RnD rather than mature tech, everyone involved is okay with this, and the company doesn't want to release its modelling of future ROI because that's valuable proprietary data and giving it away to clients and competitors is dumb.
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…
Earlier quoted context omitted.
People nowadays expect 10% return on their investment, so if you invest 1m you need to make 100k a year from it (120k to cover the deprecation over 50 years) If you made 30k a year for 50 years you'd return 1.5m from your 1m investment, but you're only making 3%, which is a low return especially given the future risk (you'd have to run for 33 years just to get your initial investment back) Either way it's worthwhile,…
> Majority of people and countries in the world do not deem ROI to be the sole or even primary driver for investment I think this is a little unfair. If it were true, it would be the reason for wealth inequality: you're saying that the majority of people and countries are so financially irresponsible that they consume any resources they get without investing any. But in fact everyone I have observed closely, in every…
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)
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…
Then again, the same also goes for the other storage methods as the spread compresses. Eventually, as always, it all comes down to who can do it on the thinnest shoestring. 1/4 the cost, but the thermodynamic efficiency is 1/3 (direct heat vs batteries + heat pump, say) is still a winner. Finns aren't going to stop needing heat in winter soon, and if you can provide it even a fraction under the cost of battery electricity and a heat pump, you get the customer. And the district heat infrastructure probably already exists.