Analysis of a solar assisted heat pump dryer with a storage tank

In north china, agriculture products may be harvested above safe storage moistures to prevent excessive field losses. A solar-assisted heat pump drying system (SAHP) with an energy storage tank has been proposed to meet the demand in this field. The drying system is designed in such a way that some of the components can be isolated depending on the weather conditions and usage pattern. The performance of the whole system has been modeled and investigated under a typical summer day of the city Baoding, China. Results show that the coefficient of performance (COP) of the SAHP drying system is 5.369, while it is 3.411 without solar energy inputs. With an energy storage tank, the SAHP drying system performs more stable and modulates the mismatch between solar radiation and the energy needed in the night. Other discussions on collector numbers, drying time and drying temperature are also processed, which will be helpful to apply the system in China.