Optimisation of Thermal Energy Storage Integration in a Residential Heating System

Domestic heating which is dominated by fossil fuels has a large share in the UK total energy consumption. Heat pumps (HP) with thermal energy storage (TES) in combination with renewable electricity generation are a viable low carbon heating option. TES allows the shifting of heating demand to off peak periods or periods with surplus renewable electricity. However, the performance of this
scenario must be critically assessed to ensure improvement relative to conventional heating systems. This study presents the design and operational optimisation of a domestic heating system consisting of an Air Source HP coupled with TES. The optimisation is performed on a synthetic heat demand model which requires only the annual heating demand, temperature and occupancy profiles. The results show that the equipment and operational costs of a HP system are significantly higher than for a conventional system. However, the integration of TES and time-of-use tariffs reduce the operational costs of the HP systems and in combination with the Renewable Heating Incentive make the HP systems cost competitive with conventional systems. It is anticipated that the demand model and optimisation procedure enable the design of low carbon heating systems which integrate the heating system with the variable renewable electricity supply.