Experimental assessment of a novel photovoltaic heat pump design with dual condenser

• Novel heat pump with two condensers and improved control was experimentally tested. • Design shifts DHW production to solar hours, boosting self-consumption. • COP improved from 3.46 to 7.59 with dual condenser and PV panels. • Solar contribution rose sharply from 9.9 % to 55.5 % with new configuration. • Results show strong potential for PV–HP integration to cut CO 2 emissions. The pursuit of near-zero energy buildings demands highly efficient domestic hot water (DHW) systems. Fossil fuels are no longer viable, and electrification alone is insufficient without high efficiency. Heat pumps (HPs) offer an optimal solution and can be considered renewable when their coefficient of performance (COP) exceeds 2.5. Although HP technology has advanced considerably, efficiency remains variable depending on operating conditions. Integrating photovoltaic (PV) systems can enhance performance, yet mismatches between HP operation and PV generation limit self-consumption. This study presents a novel HP configuration designed to shift DHW production to central daylight hours, maximizing PV utilization and system efficiency. The proposed design incorporates two condensers—placed at the top and bottom of the water tank—controlled to optimize thermal stratification and energy performance. Experimental testing compared three setups: conventional HP, HP with PV panels, and the new two-condenser HP with PV panels. Results show the COP increased from 3.55 to 4.05 with PV integration and reached 8.34 with the dual-condenser configuration at 18 °C ambient temperature. Moreover, the redesigned system shifted energy use toward PV production periods, raising solar contribution from 9.9 % to 55.5 %. The proposed configuration demonstrates significant potential for efficient, renewable DHW production.