Climate Index for District Heating System

District heating (DH) has been highlighted as an important part in future carbon neutral energy supply. However, the performance of different DH systems varies a lot and the existing regulations do not always motivate DH companies to move toward more sustainable heat production. Therefore, this article presents novel methodology for Climate index determination which can be further used for the comparison of DH systems. The Climate index includes seven different indicators which show DH system performance according to energy efficiency, sustainability and environmental impact dimensions. The methodology is applied for 20 different DH systems operating in Latvia. The results show that the performance of 5 natural gas-based DH systems is below the determined climate benchmark.