Solar multi-mode heating system based on latent heat thermal energy storage and its application

doi:10.12028/j.issn.2095-4239.2018.0216

Abstract

Abstract: To overcome the discontinuity and instability of solar energy and achieve energy supply and demand regulation and all-weather continuous heating supply of a solar heating system, a solar multi-mode heating method based on latent heat thermal energy storage is proposed. A solar heating system combining integrating vacuum-tube collectors with a latent heat thermal energy storage device is established in a building in Linzhi city, Tibet. The system can perform automatic control and operation of solar multi-mode heating according to the operating condition of solar collectors and external heating demand. Experimental studies show that the vacuum-tube solar collectors can work collaboratively with the latent heat thermal energy storage device. During the daytime, the latent heat thermal energy storage device performs a heat storage with an average charging power of 10.63 kW and a storage capacity of 92.67 kW·h, and the temperature platform of phase change can be apparently observed. At night, the thermal energy storage device can provide a 10-hour continuous discharging process with a total heat output of 85.23 kW·h at a stable discharging power and temperature. The charging-discharging efficiency of the storage device is 92%, and its heat storage density can reach 3.6 times that of a traditional hot-water storage tank. The results indicate that the solar heating system can achieve all-weather continuous heating supply. The present study can provide guidelines for implementation of solar heating in Tibet.

Key words: solar heating, latent heat thermal energy storage device, multi-mode heating, thermal storage, thermal release

CLC Number:

TK02

HE Feng, LI Tingxian, YAO Jinyu, WANG Ruzhu. Solar multi-mode heating system based on latent heat thermal energy storage and its application[J]. Energy Storage Science and Technology, 2019, 8(2): 311-318.

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