The Research On Comprehensive Benefit Evaluation Of Solar Thermal Applications In Green Building

Since the 21 st century, the contradiction of energy supply and demand turns worse with the speeding up of urbanization and consumption structure in our country. Building energy consumption accounts for about one-third of the national energy consumption, so that large-scale application of renewable and green building is one of the efficient means to reduce the contradiction between energy supply and demand. Different types of renewable energy work differently in substituting the conventional energy. Solar energy is being applied on buildings as a kind of simply and widely used renewable energy these years, and played a vital part in Green Mark. How to identify solar energy benefits and how to evaluate the effect of solar thermal applications in green building will be of great importance in reasonable evaluating the utilization of renewable energy of green building.Based on collecting abundant document and accessing to previous research, the paper clear the category of comprehensive benefit from the point of total life cycle, and established comprehensive benefit evaluation model of solar thermal applications in green building by the means of market survey, mathematical statistics and mathematical modeling, which provide references for the investors’ decisions. The main research contents and the results are as follows:(1) Start from the background of energy situation and application of home and abroad,this paper probe from the solar thermal applications technical system to the benefits of solar thermal applications in green building, and finally determine scale benefit to be the basis of the paper. All of above provide evidence to establish and quantified evaluation index system of solar thermal applications in green building.(2) From the point of total life cycle, collector efficiency, energy prices, equipmentinvestment and residual value,especially the effect of solar radiation in different seasons, are taken into account, then select net present value and dynamic investment pay-back period as evaluation index in order to analyze the economic benefit of solar thermal application system other than conventional energy application system, and finally performed sensitivity analyses to comprehensively deepen economic benefit model.(3) Using the methods of comparison as well as the combination of quantitative and qualitative, this paper analyze the effect of the environment and living standards from solar thermal application system and conventional energy application system, and establish environmental benefit model and social benefit model. On this basis, dealing with the case study to validate the models of economic benefit, environmental benefit and social benefit of solar thermal applications in total life cycle.(4) Based on the analysis about the pros,cons and the scope of the current evaluation met hods,synthesizing the advantage of the methods to subjectively or objectively,the study adopt the combination weighting approach of the analytic hierarchy process and the entropy method in order to build an model that can be used for the evaluation of the comprehensive benefit ab out solar thermal technology applied in green building,so that the evaluate result can be accor d with objective facts futher by using qualitative and quantitative analysis tool.