The role of heat pumps in the transformation of national energy systems - example Germany

The aim to limit climate change is the major driver for the transformation of energy systems globally. Renewable energies and high efficiency energy conversion on the whole chain from primary energy to net energy in all end-use sectors are key elements of highly decarbonized energy systems. Electric heat pumps in combination with highly decarbonized electricity or gas heat pumps in combination with decarbonized methane (biomass, power-to-gas) can cover a large share of the low temperature heat demand in various end-use sectors such as buildings (space heating, hot water) and the tertiary sector. Decentralized solutions in single buildings and large scale solutions in combination with district heating networks can both contribute to an efficient low temperature heat supply. In the paper results of a powerful simulation-based optimization of the transformation of the German energy system are presented and the role of heat pumps in the heat sector is be particularly highlighted. Cost-optimization clearly shows the dominant role that heat pumps must play in the heat sector under energy scenarios that lead to highly decarbonized overall energy systems. Furthermore the impact of electrical heat pumps on the residual load and thus on the total system infrastructure is investigated.