> The battery’s theoretical energy density is 260 watt-hours per kilogram
Makes me wonder how big a battery would need to be to handle all of the overwinter energy demands of some densely-populated US states.
Makes me wonder how big a battery would need to be to handle all of the overwinter energy demands of some densely-populated US states.
Density of ice at 0 degC is 0.92 kg/L. So, 1 kg of ice =~ 1087 cubic centimeters of space, or a cube ~4.25 inches on a side.
Rounding that down to 4 inches for the moment, you get 27 of those per cubic foot, or (260 Wh * 27) = 7.02 kWh, and then round that down to give the extra quarter-inch back, you get ~6.5 kWh/ft3 theoretical capacity.
A typical household in the US uses 10,715 kWh/year[0], so (10715/6.5) = 1648.46 ft3 for a household's worth of freeze-thaw battery storage, or a cube 11.81 feet on a side.
Yes, of course it's more complicated than that, but the scale is pretty interesting.
---
I imagine you'd pair this with an energy source(say solar), so that you are able to smooth out/absorb excess energy and release when its needed. You could use it as an energy supply of last resort.