The stranger in the German energy system? How energy system requirements misalign with household preferences for flexible heat pumps

By combining findings from techno-economic modelling with those from a survey of households, this article pursues an interdisciplinary approach to answer the question to what extent flexibly operated heat pumps (FHP) offer the potential to reduce the surplus generation from renewable energy sources (RES) through demand response (DR). First, we used an optimisation model to evaluate the potentials of two different DR signals to minimise the electricity costs for heat pump operation and surplus generation from RES. Second, we conducted a survey study (n = 985), the design of which was informed by the outcomes of the optimisation model. Third, we combined the findings from the two analyses to estimate market shares and link these back to the expected contribution of FHPs for RES integration. Our main findings include: even if the monetary savings due to DR were passed on fully to FHP adopters, the RES integration by FHPs would be limited due to a lack of FHP adoption. One of the main challenges is that to make FHPs useful for RES integration, an external data exchange is needed. This is, however, unattractive to consumers and thus reduces market shares. In particular, despite external data exchange allowing for higher financial savings (e110/a with data exchange vs. e57/a without), we find that FHPs without data exchange are evaluated as overall more attractive. Thus, policy measures are needed to leverage the RES integration potential of FHPs.