Strategies for decarbonising the Swiss heating system

Heating and cooling contributed to about 50% of the final energy consumption in EU 28 countries. In Switzerland, about 295 PJ of heat was consumed in buildings in 2016 which emitted about 17 million tonnes CO2. However, if the Swiss nationally determined contributions (NDCs) have to be met, the country's aggregate CO2 emissions should be between 8 and 16 million tonnes in 2050. Reduction of specific space heating demand in buildings; integrating renewable energy and increased heat distribution by district heating networks (DHNs); and use of heat pumps are three strategies which have been examined for decarbonising the Swiss heating system. It is estimated that an annual reduction of 1.5%–2.5% in the aggregate heating demand for different categories of buildings would be required. DHNs would have to be expanded from 53 networks in 2016 to about 159–212 networks in 2050 to enable integration of 53–70 PJ of ambient heat. This would require 390–520 heat pumps of 2–50 MW capacity with a coefficient of performance between 3 and 4. If these strategies are implemented, it is estimated that the aggregate CO2 emissions from heating would be between 1.25 and 3.06 million tonnes by 2050 thereby significantly decarbonising the heating system.