Design On The Solar Heating Plants With Seasonal Storage

Low-carbon economy has drawn the attention from all over the world. Solarenergy heating is energy-friendly and could greatly reduce pollutions, especially whenthe heating system is combined with assistant heat source, heat storage devices andautomatic control devices. Several factors could influent the quantity of solar energy,such as the interval of night, the weather conditions, seasonal differences and storagemethod. For tempering these factors, a new storage method of solar energy wasproposed and studied in this paper.In this method, the utilization of solar energy was combined with soil heat storage.Thus, this method cannot only fully use the solar energy in transitional seasons, but alsoovercome the variations of solar energy amount caused by time or seasons. As adifference, air, rather than other storage media, was adopted as thermal transfer medium,and soil or gravel was adopted as storage medium. This kind of design lowers the costof system greatly as well as reduces the limitations presented in other systems, likecorrosion and leakage.By now, the energy storage is one of the most feasible methods to make use ofcross-season solar energy: the solar energy could be stored in shallow layer during thespring, the summer and the autumn and the stored energy will be used during the winter.Soil was chosen as storage medium since its relatively high capacity of heat storage,amounting to50%of that of water.This design mainly included two parts: solar energy collecting system and soil heatstorage system. This system could store the solar energy in summer and transitional seasons, and then release the stored energy for building heating in winter. In this paper,greenhouse heating system and building heating system was quantitatively analyzed andthe relation among collector area, storage volume and heating area was then calculatedon the base of analysis.Lastly, the heat transfer process of the heat-exchanger pipe in storage system wasstudied as to get the distribution of temperature around the pipes. Fluent software isused to simulate the process and the three-dimensional arithmetic model of the heattransfer between heat exchanger and soil.