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1 cubic meters of water chilled 10C below ambient is 40MegaJoules of energy.

Or in other words: 11kW-hrs of cooling, comparable to an entire Tesla Powerwall.

We aren't talking about entire swimming pools here. Just a few cubic meters of water. Shift the temperature delta as you see fit but... It's actually very space efficient.

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Air conditioners have a COP of about 3 though. So really its more like 3.5kwh of storage. If you want to go lower temperature to store more then your COP drops.

The temperature delta is the hard part for me to estimate here.

I know that IceBear left the water around 45F, so take that for what you will.

Either way, we aren't talking about entire swimming pools here. Just a small, single digit number of cubic meters of water.

Typical residential air conditioning is using 4kW of power. So your 40MJ of energy would be used up in 40MJ/4kW=10000 seconds, or just 3 hours. And its only theoretical, because it assumes 100% efficiency in storage and conversion

It's odd how often battery enthusiasts don't understand the difference between energy and power.

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