That’s a good article with lots of context on the issue.
However one thing is missing: round trip efficiency figures. The whole process of turning electricity into heat, then back into electricity, is probably low efficiency.
There is discussion of directly using heat for industrial processes or heating. That’s probably a best use of energy since it avoid some energy conversation losses.
The thing is that efficency doesn’t matter too much if this energy used is from intermittent sources like wind or solar and if there is too much energy at this moment and not everything can be used. So it is better to safe energy at lower efficiency than not saving anything at all.
But the choice isn’t between heat storage+conversion and no storage. It’s between differents type of storage (heat, chemical, gravity, electrolysis, freewheel), with multiple technology and chemistry to choose from for each type.
Since there’s many options to choose from, it make sense to compare overall efficiency and cost.
Yeah, large-scale heat power plants have an efficiency of maybe 55%. Small scale heat engines are pretty hard to make work better than 30%.
Storage with solid weights is probably competitive with this for electricity. Hopefully someone figures out a low-cost grid battery.
On the other hand, if you’re running an electrically-heated concrete furnace, this is great. You heat when electricity is plentiful and coast for the rest of the time.
Yes.
The first commercial sand battery in Finland is doing just that. It’s connected to the district heating. It doesn’t convert back to electricity, but offsets the use other fuels.
That’s a good article with lots of context on the issue.
However one thing is missing: round trip efficiency figures. The whole process of turning electricity into heat, then back into electricity, is probably low efficiency.
There is discussion of directly using heat for industrial processes or heating. That’s probably a best use of energy since it avoid some energy conversation losses.
The thing is that efficency doesn’t matter too much if this energy used is from intermittent sources like wind or solar and if there is too much energy at this moment and not everything can be used. So it is better to safe energy at lower efficiency than not saving anything at all.
Yes and no.
Better store than loose energy.
But the choice isn’t between heat storage+conversion and no storage. It’s between differents type of storage (heat, chemical, gravity, electrolysis, freewheel), with multiple technology and chemistry to choose from for each type.
Since there’s many options to choose from, it make sense to compare overall efficiency and cost.
Yeah, large-scale heat power plants have an efficiency of maybe 55%. Small scale heat engines are pretty hard to make work better than 30%.
Storage with solid weights is probably competitive with this for electricity. Hopefully someone figures out a low-cost grid battery.
On the other hand, if you’re running an electrically-heated concrete furnace, this is great. You heat when electricity is plentiful and coast for the rest of the time.
Yes. The first commercial sand battery in Finland is doing just that. It’s connected to the district heating. It doesn’t convert back to electricity, but offsets the use other fuels.
https://polarnightenergy.fi/sand-battery