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250MWh 'Sand Battery' to start construction in Finland

322 points by doener

by whizzter

13 subcomments

For reference, this city is about as north as Anchorage Alaska and today they got less than 7 hours of sunlight and it'll continue to decrease for the next 3 weeks.
The Nordic countries generally still wants to increase their wind and solar power, but the big issue during winters is when there's cold air high pressure systems we get neither sun nor wind, having an energy storage that can hold up to 5 days worth of energy should help us nudge past them.
Hydro-energy exist (mainly Sweden and Norway, but I think some in Finland as well), but it's fairly built out so stable non-fossil power needs to be nuclear, or wind/sun + storage (that hasn't been good enough so far).

by retrac

5 subcomments

There's an interesting property to thermal storage, as a consequence of simple geometry. Consider a cube. volume = n³ and surface area = 6*n². Surface area increases more slowly than volume. The ratio of surface to volume decreases with more size. Thus: a sufficiently large thermal reservoir becomes self-insulating with its own mass.

by apatheticonion

8 subcomments

I was interested in trying to make a DIY thermal battery as a hobby experiment. Other than using thermal energy directly, I couldn't find a way to effectively convert the heat energy to electrical energy.
Peltier modules can be used to generate electricity, but they are crazy inefficient.
An efficient steam turbine is largely inaccessible to hobbiests and I am scared of steam/pressure. Though I did look at repurposing a car turbo for this purpose. There were additional issues with regulating the amount of heat you wanted to extract (load matching) and recycling waste heat.
I wondered if it was possible to use a Sterling engine, but you can't buy anything other than very small toys online and I don't have the facilities to machine my own.
Haha, would love to get something working, but I suppose I'm not smart enough to figure out an effective way to get that heat back out as usable/controlled electricity.

by ggm

0 subcomment

Why do so many people do "why didn't you..." As if the engineers who designed this didn't have 1002 alternatives and went with this one for reasons of budget, politics, prior knowledge, IPR costs, skills, religious beliefs, or a million other reasons.
Why did we go to the moon when we have perfectly good vacuum chambers here at home.
The implied "my way is better" in these responses is usually the bad take on "what made this better than my way" as a question which nobody really can answer unless the OP is the engineer.
"Why does Finland not deploy ubiquitous small nuclear reactors every 25 meters and make a heated road to the north you can drive over as well as get power from if you have a power adapter for finnish plugs"

by pythonguython

1 subcomments

A website called energy-storage dot news should not be mixing up energy and power

by nightshift1

5 subcomments

Interesting. Does anyone know what source of electricity is going to be used for this ? Probably solar but it might be also useful with coal plants or wind farms that produce even when there is not enough demand. How are they moving the heat ?

by bochoh

1 subcomments

In a cold climate, I would expect burying it to use the ground as a natural insulator. Why was an above ground design chosen?
Specifically, does the need for heavy insulation and the active heating of the sand make the ground a less effective or even problematic insulator? Could excavating and building a below-ground foundation for a high-temperature device like this be more complex and expensive than an above-ground silo? How would permafrost conditions affect this design?

by pfdietz

2 subcomments

These are interesting, but the cost per kWh of storage capacity is still probably too high for true seasonal storage. Short term storage runs into competition with batteries.
I point again to Standard Thermal for an idea tailored to true seasonal storage. I wait for more news from them, particularly on their very low cost resistive heater technology.
https://www.orcasciences.com/articles/standard-thermal

by chickenbig

2 subcomments

The big question is how much it will cost. For comparison I believe there is a heat battery in Germany using (atmospheric pressure) liquid water (98 C), 50M EUR for perhaps 20x the thermal storage capacity (versus 20 C water).
The use of sand, presumably heated to a much higher temperature than the boiling point of water, seems overkill for district heating (unless peak heat demand requires flow temperatures above 100 C). But it does reduce the volume of sand required, so the size of the storage system.

by octaane

1 subcomments

It's probably my ignorance about this sector, but I do find it impressive that they are getting that much storage capacity in a small area:
> "This latest project will use locally available natural sand, held in a container 14m high and 15m wide."

by xarope

2 subcomments

would someone give an ELI5 on how a sand battery works? Is it just purely thermal mass, just with tons of sand?

by nickdothutton

1 subcomments

Those of us in the UK will recognise this as a giant "Economy 7 Night storage heater".

0 subcomment

by ionwake

0 subcomment

I like how sand batteries are the equivalent of sleeping on the ashes of your fire

by tempodox

0 subcomment

This is great news! Congrats for this fantastic progress.

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by tonyhart7

1 subcomments

I never see sand battery before
between this and salt battery which one is the future???

by kineticdaffodil

0 subcomment

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by penissucker4167

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by pcdoodle

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by timonoko

2 subcomments

[flagged]

by Ericson2314

4 subcomments

EU is going to have to either
- embrace nuclear
- embrace North Africa, admitting them as member states, and doing massive solar there, and doing massive grid expansion to carry it north. And then in top of that, will their way to sufficient storage like the rest of us.
We'll see what they choose :D

by timonoko

4 subcomments

Finland's current energy equation according to Google Gemini:
```
  Is Finland importing household garbage from Italy and why?
```
Gemini: ... In summary, Finland imports waste (mainly as pre-processed fuel) to feed its modern waste-to-energy plants, which are a key part of its heating and energy strategy, especially as domestic residual waste volumes decrease due to better recycling and as a replacement for former Russian renewable fuel imports.
```
  Why you call it "processed"? It is raw garbage in huge mounds smelling bad and harboring flies and rats?
```
Gemini: ... This processing turns smelly, inconsistent "garbage" into a stable, high-quality, non-hazardous secondary fuel that is compliant with strict EU waste shipment and energy production regulations. The whole point of the import is to fuel power plants efficiently, which requires this specific, processed product.
```
  Lets try again. Why the "processed" mound of garbage from Italy smells bad and houses flies and rats?
```
Gemini: ... Sometimes ....
```
  This is not "sometimes", it makes living near     Loviisa harbour impossible.
```
Gemini: ... It is clear that the environmental integrity and quality of life for residents of Loviisa have been compromised by the need to fuel Finland's waste-to-energy capacity with large, sometimes substandard, imports. etc etc.
===
Short summary: The Pro-Russian Green "Pedophile"-Party destroyed the existing energy infrastructure which ran on coal from Poland etc. A new system was built to use "renewable" Russian gas and Russian wood industry leftovers.
The situation is desperate; any shit from anywhere at any cost is better than using local renewable biomass, such as peat.
Finland has enormous amounts of peat, which is worth more than Norway's oil reserves.