Harnessing of Geothermal Energy for a Greenhouse in Ecuador Employing a Heat Pump: Design, Construction, and Feasibility Assessment

Abstract

The world greenhouse farming area is about 500 000 ha, and more than half of vegetables grow in a greenhouse. Nevertheless, high-grown yields tend to be especially energy-intensive. Therefore, the use of alternative energies is necessary to meet the growing demand. This study proposes designing and building a coupled geothermal heat pump system for a 470 m2 greenhouse located in the Andean zone of Ecuador, which requires 15°C at night and 30°C during the day. For doing so, we calculated the energy supply of both the solar and geothermal sources, then we carried out an energy balance in the greenhouse and sized the horizontal geothermal heat pump (HGHP). Following, we evaluated the technical feasibility and built the system, including the geothermal reservoir. Finally, we assessed a financial analysis based on the Leveled Cost of Heat (LCOH) and compared its performance with similar systems in other latitudes. Technically, the operation is feasible and requires a potential of 29,56 and 65,76 kW for heating and cooling. From a financial point of view, this type of technology in Ecuador needs economic incentives to compete with traditional sources such as electricity and LPG. The results allow future research to focus on determining the influence on the productivity of crops grown in thermally conditioned greenhouses.