“Without the option of “clean” natural gas, Sweden turned to district heating – an idea which had originated in New York in the 19th century. But Sweden committed to it in a big way during the 1960s and ‘70s, deciding it was the best way to meet the heating needs of the 1 million homes now being built. This decision shaped the way homes in Sweden are heated: today, some 90% of its multi-family apartment blocks are connected to district heating systems – with heat distributed from power plants (usually on the edge of cities) as hot water via a network of pipes.”