Comprehensive Evaluation And Analysis Of Solar Combined With Biomass Heating Systems In Villages And Towns

China’s northern building heating energy consumption amounts to 214 million tonnes of standard coal.Under the impetus of clean heating policies,solar combined with biomass heating systems are being developed in village and town areas,however,research on the comprehensive evaluation of this system is still in its infancy,and a scientific and reasonable evaluation of the system is of great significance for system improvement and reflecting its advantages.In this thesis,the evaluation index system of solar energy combined with biomass energy heating system in villages and towns with 11 evaluation indexes is constructed,which takes energy efficiency,economic efficiency,environmental efficiency and indoor environment as the criteria.The combined weighting method is determined as the index weighting method,and the approximate ideal solution ranking method based on European distance and grey correlation degree is determined as the comprehensive evaluation method.Based on the above theoretical research,a comprehensive evaluation model for rural solar energy combined with biomass energy heating systems has been established.An evaluation index system of solar energy combined with biomass heating system in villages and towns with energy efficiency,economic efficiency,environmental efficiency and indoor environment as the criteria and a total of 11 evaluation indexes was constructed,and the combined assignment method was determined as the index assignment method,and the Technique for Order Preference by Similarity to Ideal Solution based on Euclidean distance and Grey correlation degree as the comprehensive evaluation method.Based on the above theoretical research,a comprehensive evaluation model of solar energy combined with biomass heating system in villages and towns was established.The experiments measured the operational data of five users during the heating period;the access to each indicator and the calculation method were clarified,and the indicators were obtained quantitatively.The indicators were classified into 4 grades of excellent,good,average and poor with reference to the criteria,and the range of classification of each grade was determined.The indicators were rated separately for each user and the results were obtained,in which User 3 and User 5 both had 6 indicators rated as excellent,User 2 had 4 indicators rated as excellent and User 1 and User 4 both had 2indicators rated as excellent.Questionnaires were distributed to the expert group and the general user group to obtain the scores of the indicators,and the subjective weights of the indicators were determined using the improved hierarchical analysis method.Based on the parameters of the five groups of user indicators,the objective weights of the indicators were determined using the entropy weighting method;The combination of subjective and objective weights based on the game theory linear combination method determines the combination weights of the indicators Among the criteria,economic efficiency B2 has the largest weight,W_B2=0.3011,indoor environment B4 has the smallest weight,W_B4=0.1922;among the indicators,the present value of comprehensive heat price C6 has the largest weight,W_C6=0.1296,and system heating efficiency C1 has the smallest weight,W_C1=0.696.A comprehensive evaluation of the application effectiveness of the five user systems was carried out using the Technique for Order Preference by Similarity to Ideal Solution based on Euclidean distance and Grey correlation.All five users were rated good overall,with User 5,User 3,User 2,User 1 and User 4 ranked in descending order of rating,with User 5 having a better heating effect than the others.The criteria were evaluated and it was found that all criteria ratings for user 5 were good and above,and user 4 was rated below excellent for each criterion,a result that matches the ranking trend of the overall evaluation.