Seasonal heat storage exists.

Basically a big water tank with very thick insulation which can store heat for six months. This is economical for multi-family units, becauses the relative amount of necessary insulation decreases with size (for a cube with 27 cubic meters volume, you need 54 square meters of insulation, for a cube with a volume of 125 cubic meters, 150 square meters).

What can store a hot medium can obviously also store a cold medium.

It is also much cheaper to store heat, than to store electricity.

Here is a description (in German) of applying the concept to a single-family home.