Design And Research Of Medium And Low-grade Solar Building Cooling Heating And Power System

With the rapidly development of science and technology around the world, the demand of energy sources also increases day by day. The current main energy resource in China is from the consumption of coal, in which problems such as structure unreasonable, ultilization of energy low, pollution heavy always exist. Therefore, the study and application on efficient and environmental resource has become the focus in this world. By now, the applications of solar energy and wind are leaders in near energy field. There’s abundant solar energy in our country, which enables the efficient use of solar energy become an important part in the mordenized development of the country. This paper presented the research status and development tendency of mid-low solar energy application, studied different patterns of mid-low solar application, and designed a conbined cooling heating and power(CCHP) system using organic rankine cycle(ORC).First of all, this paper introdued and contrasted main forms of solar thermal generation. Main principles of CCHP system and its development status were presented. And the focus and development direction were also discussed.Secondly, the mid-low temperature solar system assembled in this paper involved ORC system, for ORC had advantages like good performance in mid-low temperature, lower operation temperature, excellent antifreezing property, and lower system cost. Besides, system with ORC could keep the inner pressure above the atmosphic pressure. A mid-low solar thermal system was constructed. And the simulation of this system was conducted by setting initial conditions. Simulation results were analyzed to realize the starting, braking, testing and controlling the ORC system.At last, with modeling the thermal load of heating, cooling, hot-water, and power generation in a CCHP system, the total model of the system was constructed. Operation of the system in summer and winter were simulated and analyzed respectively, in which different load powers in the system were obtained.Main works in this paper were embodied in how to choose proper working medium, how to constructe system unit, how to simulate the system and analyze the simulation results, and how to optimize the CCHP system. The CCHP system proposed in this paper was designed on principles of energy conservation, environmental protection, and economy. And by construction of mid-low temperature solar CCHP system, the cascade ultilization that high-temperature generation, mid-temperature cooling or heating, low-temperature domestic hot water was eventually realized.