The building I inhabit in Paris receives municipal geothermal heat with a possible supplement from natural gas plant co-generation.

For more info: Insight into Geothermal Reservoir Management District Heating in the Paris Basin, France [pdf]

It's been a brilliant initiative, if poorly implemented on the local level. Heat arrives in this 1960s-designed building in the form of forced air, the vents for which are placed at ceiling level [!]. So, when I do turn on the heat, the upper 20cms of the apt stay very nice and warm. Perfect for the spiders.

Though in fact I rarely need to use heat any more. It's a poor sign re GCC but, generally, in winter, I can get by with a bit of extra clothing, now.