Investigation of temperature changing on heat storage in the greenhouse

In this study, main aim is improved a new alternative heating systems for greenhouses.An experimental set-up designed to investigate the effect of the heating of the greenhouseswith solar energy and heat pump experiments were done in Turkey-Elazığ.Ground-source heat pump (GSHP), also known as geotermal heat pump (GHPs), arerecognized to be outstanding heating, cooling and water heating systems. Greenhouses alsohave important economical potential in Turkey?s agricultural sector. In addition to solarenergy gain, greenhouses should be heated during nights and cold winter days. In order toestablish optimum growth conditions in greenhouses, renewable energy sources should beutilized as much as possible.The experimental set-up (apparatus) consist of 10 numbers solar air collectors , a glassgreenhouses with dimensions of (6mx5mx2m). A latent heat thermal thermal energy storagetank were used in the experiments. This tank was filled with phase-change material (PCM). Alatent heat thermal storage tank (LHTST) were used to heat, and also to charge of PCMduring day light and to discharge heat in PCM during nights days. In the experiments made incold winter days when the solar air collectors is not sufficient a heat pump with groundsource, heat exchanger, a circulating pump, measuring and other axuliary equipment wereused.In this study, First period solar air heating system was used for heating in thegreenhouse. Secondly solar air heating assisted with energy storage system was used. Finallyground source heat pump and energy storage system were investigated experimentaly.Experiments were made during the heating season ( from October to May) of 2005 and 2006.The experimentally obtained results were used to calculate collector efficiencies,storage efficiencies, heat pump coefficient of performance (COPs) of the sytem. From theeconomical analyses, It was shown that solar air collectors using heating in this region is themost economical system in the day- light. Ground source heat pump can be used for Elazığ,Turkey climate conditions.Keywords: Heat pumps (HP), Solar Air Collector (SAC), Horizantal Ground Source HeatPump (HGSHP), Latent Heat Storage (LHS), Phase Change Material (PCM).