Paper No 301 – Control strategy assessment of a small GSHP sourced DH system with end user DHW booster heat pumps – 13th IEA Heat Pump Conference, Jeju, Korea
A small thermal grid for historic Almshouses 'the Schipjes' in Bruges was designed in 2016 and is nearing the final phase of construction while partly in operation. The houses' building envelopes were retrofitted with respect to the monumental character to decrease the heating demand and the required temperature levels. The houses are connected to a low temperature thermal grid supplied by a hybrid of a ground source heat pump (GSHP), solar thermal panels (ST) and a condensing gas boiler (not installed after predesign simulation). Domestic hot water (DHW) at higher temperature in the individual houses is provided by booster HP's, while room heating (RH) is provided by floor heating and radiators.A limitation of thermal power creates a challenge to verify which rule based control (RBC) operates optimal for this case. The study simulates the project using Modelica. RBC variations are simulated in which temperature levels in the system, anticipation, building integrated or central vessel storage are implemented. For each variation the resulting comfort, the share of renewable energy supply (RES) and the electrical energy use (COP) are quantified. Conclusions are a.o. that building integrated storage is needed for the load management, as well as a heating curve for the further increase of the RES system performance. The individual variations lead to a decrease of discomfort by 17%, an increase of RES by 7.4% and a decrease of electrical energy use of 25% on an annual basis