Big towns have a some degree Celsius more warm climate than the green surroundings. This has not to be like this, however a mad energy wastefulness costing us much money.
Double energy wastefullness
In the summer time, sun heats up the roofs of the houses. When the buildings have in a big town a big part of the total surface, this means a general heat up of the whole town area. Every weekend, many people flee from the town area. Big traffic jams Sunday in the evening, when all this people return in the unloved town.
The energy from the warm roofs is wasted. The inhabitants driven out by the unpleasant urban climate in endless rows of vehicles driven by ICE combustion engines.
On the other hand in winter, all the houses are heated by burning fossile fuel. An insanity of the crude oil age.
Cool roofs, store heat, climate regulation
The underground below a town from 20 to 100m depth as a gigantic season storage. In summer the heat from the roofs is stored in the underground. The underground becomes warmed up by some degree Celsius. In winter, the heat stored in summer is used to warm the houses by heat pumps.
Good insulated houses with heat recovery at air exchange do not need so much heat like taken from the roofs in summer to regulate the climate. What to do with this waste heat? Less salt to make in winter the streets free from snow and ice, because it's possible to warm the streets? Glas covered shopping streets in winter with 10 degree Celsius?