Towards a 100% renewable energy share for heating and cooling in office buildings with solar and geothermal energy

An integrated energy system for office buildings is examined, with the use of a numerical tool that has been developed simulating renewable energy-based systems based on geothermal and solar energy. The main components are PV-Thermal (PVT) collectors, several boreholes form ground heat exchanger multi-source pump supplied by either from ambient air or water. code in Python used detailed investigation performance over time, components’ sizing, as well analyzing various layouts. Different demand profiles have considered according to insulation level building, total PVT collector surface varied about 50 100 m². Focus given here share covering heating cooling typical building warm climate (Athens, Greece) cold one (Copenhagen, Denmark). Technical environmental indicators presented compared standard solutions. results show can operate few moments during day charge buffer tank, introducing high flexibility. Moreover, annual COP winter 4 Athens 3.8 Copenhagen. Self-consumption exceeds 30% some cases Athens, whereas up 11% Finally, considering rooftop limitations it possible reach 82% 61% adding PV panels moderate efficiency Copenhagen, respectively.