Investigation on hybrid system design of renewable cooling for office building in hot and humid climate

In this study, a hybrid renewable cooling system (HRCS) is proposed for office building application by utilizing both the solar energy and the ground source. With the basis of solar absorption cooling, part of the building sensible cooling load was shared by the ground-source radiant cooling. Although the solar absorption cooling system or the ground source heat pump system has been individually proven energy-efficient, the area of solar collectors or size of borehole field would be limited by the available space for accommodation. In this regard, the system performance through joint contribution of renewable energy sources was investigated for building air-conditioning purpose. In the HRCS, appropriate design and operation between the ground-source radiant cooling and the solar absorption cooling was worked out. Through year-round dynamic simulation, it was found that the HRCS could have 43.8%, 53.3%, and 68.0% primary energy saving when compared to the sole ground-source heat pump system, the sole solar absorption cooling system, and the conventional vapour compression air-conditioning system, respectively. This demonstrates the merit of hybrid utilization of solar energy and ground source, and the strategy of renewable cooling is robust for sustainable air-conditioning and green building design in hot and humid climate.