Abstract:
Residential heat pumps are one of the most resource-efficient means for space heating. Their market shares are prospected to rise substantially within the next decades. By installing a thermal energy storage, the operation of heat pumps is - to a certain extent - decoupled from heat demand. Such flexibility is frequently claimed to bear high potentials for demand side management. In this study, we investigate the operational cost savings achievable through such a flexibility option using a dynamic model of the coupled building and heating system combined with model predictive economic control strategies. We derive several model predictive control strategies based on real-time prices for a heat pump in combination with a thermal energy storage supplying a floor-heated building. The algorithms are applied using perfect and imperfect foresight. Furthermore different variations of real-time prices are investigated, considering both historic and future years. Also the markets considered and the level and structure of end consumer charges (being a substantial part of the electricity price) are varied. The obtained operational cost savings are contrasted with different paths of investment cost developments. Results show that - even under optimistic conditions - investments in flexibility measures (additional storage capacity, etc.) are not economically viable.