[nray]

Many Swedish suburbs are supplied with communal hot water for heating (fjärrvärme) produced by burning non-recyclable rubbish or maybe a local factory. The last stage of houses built near us was so thermally efficient that the supplier refused to extend the heating network, as there was not enough consumption to generate a profit. When I lived in New Zealand I could see my breath indoors in the winter. Insulation? I'm a convert.