Predicting the Performance of a Solar Domestic Water Heating System with Evacuated Tube Collectors and Hydronic Radiant Flooring

摘要

Residential solar thermal system installations have been significantly increasing in the last decade and there exists limited resources for reasonably predicting the performance of those systems. A simulated model is developed in MATLAB® and used to predict the performance of a solar domestic water heating system. In the simulated system, hot water is generated using evacuated tube solar collectors and stored in a domestic hot water storage tank, which utilizes immersed coil heat exchangers. The system is designed to provide hydronic radiant floor heating to its occupants based on the heat loss of a building energy model for an energy-efficient home. Performance characteristics of the components from well-known manufacturers are utilized where available. Some of the parameters are easily changeable so that several manufacturersu27 characteristics could be compared using the model. The systemu27s sensitivity to tank thermal stratification and tank size are investigated. For solar intermittencies, the energy required for auxiliary domestic water heating is determined by the model as well. Some empirical investigations of two sets of evacuated tube collectors were used to compare the validity of the model. Results are presented in terms of temperatures and heat gains.