Research Of Distributed Energy Systems Coupled With Solar Energy And Fuel Cell

Fossil energy consumption leads to more environmental problems. Changing energy utilization patterns, improving energy efficiency and developing renewable energy are important ways to mitigate energy and environmental issues. Solar energy is one of green energy for its wide distribution and inexhaustion, and fuel cell system is one of supply method with high efficient, energy saving and environmentally friendly. Distributed energy system(DES) coupled solar energy with fuel cell can not only achieve the continuous and efficient use of solar energy,but also has great potential in the field of energy saving and emission reduction.Firstly, according to the thought of using solar energy alone to achieve energy supply, the DES based on solar thermal power generation is integrated and designed.A DES driven by solar thermal energy and fuel cell are coupled with electrolyzer.When the intensity of solar radiation is abundant, the excess electricity is utilized to produce and store hydrogen. When solar energy is inadequate, fuel cell driven by the stored hydrogen is used to supply energy. The thermodynamic analysis in the summer and winter design conditions was presented based on the first and second thermodynamic laws. In addition, the effects of the solar radiation intensity and turbine inlet pressure on thermodynamic performance of DES driven by solar thermal energy were analyzed.Secondly, according to the thought of solar energy and fuel complenmentation,the DES based on solar thermal-methanol reforming is integrated and designed. The system utilizes methanol steam reforming to produce hydrogen and then achieves energy supply by the fuel cell system. The hydrogen producted by the methanol steam reforming was simulated by Aspen Plus software to find the optimal conditions. The thermodynamic analysis in the summer and winter design conditions was presented based on the first and second thermodynamic laws. The influence of varying solar radiation flux on the thermodynamic performance of the distributed system was analyzed.Finally, on the basis of fuzzy theory and analytic hierarchy process, the two DESs were comprehensively evaluated from technology, environment and society aspects. The weight of each index was calculated through the combination of subjective weighting and objective weighting. Then the comprehensive performance of two schemes is compared using the method of technique for order preference by similarity to ideal solution.