[mfringel]

Just to put some numbers around that...

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.

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[0] https://www.eia.gov/tools/faqs/faq.php?id=97&t=3