A novel liquid desiccant-based hybrid system of building integrated photovoltaic-thermal system and ground heat exchanger for buildings in hot and humid climate

Today, using integrated renewable energy systems in residential buildings is a solution that, in addition to reducing energy consumption in this sector, also leads to proper placement and economic efficiency. In this study, an innovative integrated solar-geothermal system consisting of a building integrated photovoltaic-thermal system, the ground heat exchanger, and the liquid desiccant system with low regeneration temperature is investigated to provide electricity, domestic hot water, space heating and cooling annual needs of a residential building located in a dense urban fabric of hot and humid climate. The energy, economic, and environmental analyses of the integrated system are dynamically studied using TRNSYS-MATLAB co-simulator. By defining a system control method, the integrated system is able to provide about 2500 h of the total space cooling needs passively by only the ground heat exchanger, while the ground temperature has a very little change in the long-term. Also, using the integrated renewable energy system, the building energy consumption is reduced by about 32 %, and the system overall efficiency is obtained about 45 %. The economic analysis showed that the risk of initial investment return in less than 8 years and the risk of increasing the internal rate of return to more than 18 % for the integrated system are 49 % and 17 %, respectively. Also, based on the results of the stochastic model, the levelized cost of electricity of the system varies between 2.25 $/kWh and 4.10 $/kWh. It is found from the environmental analysis that all the environmental impacts of the proposed system are lower than the conventional system except ADPE and FW indexes.