On the impact of heat pump installations and peak blocking strategies on grid expansion costs

The increasing number of heat pump installations in Germany will require additional grid expansion and grid reinforcement measures. Grid operators call for measures to block heat pumps during critical, high load phases. However, the exact implementation of possible heat pump blocking periods and their impact on grid expansion costs remains unknown. This paper introduces a framework to evaluate the impact of heat pump blocking mechanisms on grid expansion cost, based on real-world household and heat pump load profiles. We show that previously suggested approaches in the literature, such as blocking all heat pumps in the grid during peak hours, lead to significant increases in distribution grid expansion costs due to catch-up effects. In addition, we introduce an open-source simulation model to assess the impact of heat pump blocking mechanisms on aggregated heat pump loads and peak loads at low computational costs.