size and weight of a car

blocks of ice measuring 4 ft × 4 ft × 2 ft.

This you?

Because 32 cubic ft is about the volume of most residential AC units.

Is it?

92kWh/m^3 of energy is a lot of cooling. It’d be hard to not be effective.

I think youre misunderstanding one thing, which is that the ice is a replacement for batteries. While the system had a small battery for running a small pump and fan, its a small cheap one that doesn’t store much and the water has substantially more energy, equivalent to something like a large lithium battery.

The thermal battery is also far smaller, cheaper, and more robust than a lithium battery and it won’t deteriorate with repeated cycling. The obvious trade off is that in this case it can only be used for refrigeration and only down to 0C. So while its very niche, it is quite effective for home air conditioning.