| Abstract |
High-efficiency cogeneration and district heating and cooling infrastructures (DHC) have a huge potential to strongly reduce the consumption of fossil fuels and their impact on the climate, by means of the synergic optimization of production, transport, integration and management of all potential energy sources available locally. This constitutes the basic approach for the Italian DHC developed in the last 30 years. By the end of 2011 there were 104 cities and towns supported by DHC, totalizing a space heating of 260 millions of m3, 1,32 million tons of avoided CO2 emissions and a primary energy savings of 405.000 TOE, with an annual increment rate of + 6,5 %, mainly achieved by extension of existing district heating networks. Among the energy sources feeding the DHC, the natural gas covers over 75 % of the total, whereas heat recovery from WTE (waste to energy) plants represents the second energy source. The contribution of renewable sources increased substantially from 3 % in 1995, to 20 % in 2011, mainly due to the new entry of the biomasses and to a consistent increment of the heat recovery from WTE plants. The contribution of the geothermal sources and of the industrial heat recovery is nowadays still marginal (0,8 %), though large margins of potential improvement in the near future are expected from new geothermal projects, solar thermal and heat pumps. |