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A zero-carbon northern Europe that replaced all gas heating with heat pumps would benefit from being able to store electricity during the warm summer months, to

A zero-carbon northern Europe that replaced all gas heating with heat pumps would benefit from being able to store electricity during the warm summer months, to power heating in the cold winter months. There are other options, of course - new nuclear plants, importing renewable power from countries with better weather, huge numbers of wind turbines, and so on - but cost-effective long-term power storage would address some issues if it was available.

nl 4y ago
The times when there is insufficient wind and insufficient solar somewhere within transmission range of Europe are so small (hours) that this long term energy storage isn't something anyone is trying to build. Better long distance transmission infrastructure is a much better solution to this.
- ilyt 4y ago
  Winter happens at same time in Europe. Unless we're talking shipping all the way from Africa
  - lovemenot 4y ago
    Offshore wind is already at large scale in N. Europe and will continue to add much more capacity. Winds are stronger in winter time.
  - nl 4y ago
    Winter is excellent for wind power.
- hollerith 4y ago
  Until something adversarial happens to your transmission infrastructure similar to what happened to Nord Stream 1 and 2 a few months ago.
  - nl 4y ago
    Yes, black swan events happen for all kind of power sources. Depending on your risk tolerance you overbuild to reduce that. Same as with all types of energy production.
- adrianN 4y ago
  There is a tradeoff between overprovisioning renewables, improving transmission networks and storage. Where the cheapest solution lies is not clear yet.
Schroedingersat 4y ago
> A zero-carbon northern Europe that replaced all gas heating with heat pumps would benefit from being able to store electricity during the warm summer months, to power heating in the cold winter months. Why store winter heat as work when you could just store it as heat or chemical energy? All you need is a hole, some plastic sheeting, an element, and some pipes to store many GWh. Alternatively one of many cheap phase change materials, thermochemical stores, or some low grade sand unsuitable for construction.
jodrellblank 4y ago
How feasible is that at all? "According to Ofgem, the average household in the UK has 2.4 people living in it, and uses 8 kWh of electricity and 33 kWh of gas respectively, per day." Lump those together, halve it for the magic of heat pumps but then add some back because winter will be above average use, call it 30kWh/day. Three months of winter is ~90 days, and ~30 million households, is storage of 30,000 x 90 x 30million = 81,000,000,000,000; eighty one trillion Watt-hours. A classic (non-EV) car battery stores ~1kWh, so eighty one billion of them to store that kind of power. Thousands per household. Even to store ten percent of it is hundreds of car batteries per household which is still unfeasible, and not going to get you through winter.
- dTal 4y ago
  That's exactly the appeal of flow batteries - for gigantic capacities, all you need is big tanks. Working your example - google tells me that zinc-iodine electrolyte gets you about 200 Wh per liter. Therefore you need about 400 million cubic meters of storage for the capacity you suggest. To estimate the cost of this, I looked at reservoirs. The largest drinking reservoirs in the world are in Qatar, where they have built 5 tanks of 436,000 cubic meters each. Therefore we'd need about 200 of those facilities. The cost was around 5 billion dollars, so our total cost would be around a trillion dollars. This is obviously a lot! But not unimaginable - the government borrowed over 300 billion pounds in the 2020 fiscal year alone just to pay for Covid. In practice you'd need considerably less than 90 days of continuous power, because the wind does blow and the sun does shine even in winter. All you really need is tanks to buffer the difference in renewable capacity between winter and summer, which is certainly not 100%. And the system can be built up incrementally over a long period of time, and still yield value - we don't need to spend a trillion dollars all at once. And in the worst case - you can erode the fraction of load taken on by renewables with nuclear (doesn't look so expensive now eh?). Obviously take all these numbers with a grain of salt, this is a back-of-the-envelope calculation built on another back-of-the-envelope calculation (in particular, I haven't included the cost of the electrolyte). The point is merely to show that it's not orders of magnitude outside our ability.
  - jodrellblank 4y ago

nl 4y ago

The times when there is insufficient wind and insufficient solar somewhere within transmission range of Europe are so small (hours) that this long term energy storage isn't something anyone is trying to build. Better long distance transmission infrastructure is a much better solution to this.

ilyt 4y ago
Winter happens at same time in Europe. Unless we're talking shipping all the way from Africa
- lovemenot 4y ago
  Offshore wind is already at large scale in N. Europe and will continue to add much more capacity. Winds are stronger in winter time.
- nl 4y ago
  Winter is excellent for wind power.
hollerith 4y ago
Until something adversarial happens to your transmission infrastructure similar to what happened to Nord Stream 1 and 2 a few months ago.
- nl 4y ago
  Yes, black swan events happen for all kind of power sources. Depending on your risk tolerance you overbuild to reduce that. Same as with all types of energy production.
adrianN 4y ago
There is a tradeoff between overprovisioning renewables, improving transmission networks and storage. Where the cheapest solution lies is not clear yet.

Schroedingersat 4y ago

> A zero-carbon northern Europe that replaced all gas heating with heat pumps would benefit from being able to store electricity during the warm summer months, to power heating in the cold winter months. Why store winter heat as work when you could just store it as heat or chemical energy? All you need is a hole, some plastic sheeting, an element, and some pipes to store many GWh. Alternatively one of many cheap phase change materials, thermochemical stores, or some low grade sand unsuitable for construction.

jodrellblank 4y ago

How feasible is that at all? "According to Ofgem, the average household in the UK has 2.4 people living in it, and uses 8 kWh of electricity and 33 kWh of gas respectively, per day." Lump those together, halve it for the magic of heat pumps but then add some back because winter will be above average use, call it 30kWh/day. Three months of winter is ~90 days, and ~30 million households, is storage of 30,000 x 90 x 30million = 81,000,000,000,000; eighty one trillion Watt-hours. A classic (non-EV) car battery stores ~1kWh, so eighty one billion of them to store that kind of power. Thousands per household. Even to store ten percent of it is hundreds of car batteries per household which is still unfeasible, and not going to get you through winter.

dTal 4y ago
That's exactly the appeal of flow batteries - for gigantic capacities, all you need is big tanks. Working your example - google tells me that zinc-iodine electrolyte gets you about 200 Wh per liter. Therefore you need about 400 million cubic meters of storage for the capacity you suggest. To estimate the cost of this, I looked at reservoirs. The largest drinking reservoirs in the world are in Qatar, where they have built 5 tanks of 436,000 cubic meters each. Therefore we'd need about 200 of those facilities. The cost was around 5 billion dollars, so our total cost would be around a trillion dollars. This is obviously a lot! But not unimaginable - the government borrowed over 300 billion pounds in the 2020 fiscal year alone just to pay for Covid. In practice you'd need considerably less than 90 days of continuous power, because the wind does blow and the sun does shine even in winter. All you really need is tanks to buffer the difference in renewable capacity between winter and summer, which is certainly not 100%. And the system can be built up incrementally over a long period of time, and still yield value - we don't need to spend a trillion dollars all at once. And in the worst case - you can erode the fraction of load taken on by renewables with nuclear (doesn't look so expensive now eh?). Obviously take all these numbers with a grain of salt, this is a back-of-the-envelope calculation built on another back-of-the-envelope calculation (in particular, I haven't included the cost of the electrolyte). The point is merely to show that it's not orders of magnitude outside our ability.
- jodrellblank 4y ago