However, the oldest system in the world, still working according to the original principles, is the Chaudes-Aigues system in France. District heating systems have mainly been developed during times of high energy prices and the driving force has been the possibility of achieving higher overall energy efficiency. In the days of low energy prices, existing district heating systems survived by virtue of the convenience it offers to its customers. Few people today need to spend time or effort heating their homes. District heating is paid for by simply pushing a keyboard button in an Internet-based payment routine.
District heating offers effective potential to reduce carbon dioxide emissions.
The five fundamental ways of reducing carbon dioxide are substitution of fossil fuels, deposition of carbon dioxide, lower demand, higher efficiency in energy conversion and retrieval of conversion losses in energy conversion processes. District heating makes it easier to utilise the first and fifth ways. District heating is a source of support for many people in their everyday lives. How-ever, the technology of district heating has few advocates at the universities of technology around the world. The adjunct professorship in District Heating Systems Technology at Chalmers is the only professorship in Sweden solely devoted to district heating.