No, flywheel is not cheap enough and too complicated. Pumped hydro is cheapest, but only available at very few location. Lithium batteries are a waste or misappropriation (lithium should be recycled for mobile use) and there aren’t enough.
The two battery types that seem to work are liquid metal batteries that are made out of dirt cheap and abundant materials (although there might be problems there still), and flow batteries. Kite power also seems to provide more energy for less material costs (no huge foundations and towers needed).
The gravity energy system would be able to store 2MW of power and integrate into the local energy grid.
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Scientists from the International Institute for Applied Systems Analysis (IIASA) found that the world’s abandoned mine shafts could store up to 70TWh of power - roughly the equivalent of global daily electricity consumption.
Finnish researchers have installed the world’s first fully working “sand battery” which can store green power for months at a time.
The developers say this could solve the problem of year-round supply, a major issue for green energy.
Using low-grade sand, the device is charged up with heat made from cheap electricity from solar or wind.
The sand stores the heat at around 500C, which can then warm homes in winter when energy is more expensive.
There are different options, not each one is suitable for every place, but seams possible that combination can help us achieve needed reduction in fossil fuel usage when sun is down and no wind.
Aren’t flywheel energy storages (invented by James Watt and improved over time) not suitable energy storages for electrical grids?
No, flywheel is not cheap enough and too complicated. Pumped hydro is cheapest, but only available at very few location. Lithium batteries are a waste or misappropriation (lithium should be recycled for mobile use) and there aren’t enough.
The two battery types that seem to work are liquid metal batteries that are made out of dirt cheap and abundant materials (although there might be problems there still), and flow batteries. Kite power also seems to provide more energy for less material costs (no huge foundations and towers needed).
There are also gravity batteries: https://www.euronews.com/green/2024/02/06/this-disused-mine-in-finland-is-being-turned-into-a-gravity-battery-to-store-renewable-ene
Also in Finland, but different technology “sand batteries” https://www.bbc.com/news/science-environment-61996520
While I think there is still no working production model, Iron Salt Batteries are very promising https://en.wikipedia.org/wiki/Iron_redox_flow_battery
There are different options, not each one is suitable for every place, but seams possible that combination can help us achieve needed reduction in fossil fuel usage when sun is down and no wind.