Study On The Suitability Evaluation Index And System Of Direct Electrical Heating In Villages And Towns

Implementing decentralized direct electrical heating for rural areas in remote locations where central heating is difficult to popularize is one of the effective ways to achieve clean heating,slow down the consumption of coal resources,and promote the replacement of renewable energy in rural areas.Aiming at the problems of unsatisfactory application effect,high cost and lack of comprehensive suitability analysis of direct electrical heating in rural areas,this paper establishes a suitability evaluation system of direct electrical heating for villages and towns.According to local conditions,this paper provides guidance and suggestions to choose heating schemes and use clean electric heating economically and efficiently.In order to obtain basic information on heating conditions in rural areas,this article conducted a questionnaire survey on 421 rural hou seholds from six aspects:household information,building conditions,winter heating conditions,residents’ heating habits,cooking/lighting/electrical appliances usage,and electricity usage.Based on the descriptive statistical analysis of the questionnaire data u sing the statistical analysis software SPSS 22.0,combined with the experience of some "coal-to-electricity" pilot provinces and cities,the case of a certain scale of thermal storage/direct-acting electrical heating reformation in villages and towns is analyzed.The preliminary determination of the suitability conditions for direct electric al heating includes: difficult to implement central heating,households’ annual income level matching heating costs,intermittent heating,conducive to energy-saving behavior,preferential heating prices,heating subsidies,ability of increase grid capacity or renovation indoor lines,reliable power supply,in line with local resource advantages.In order to summarize the practical indicators that reflect the complex heat ing situation in rural areas,the factors that significantly affect the application of electric heating in villages and towns are explored.The dependent variable is the application of electric heating in villages and towns in three categories including el ectric energy as the main heating energy,auxiliary heating energy and heating without electric energy.The independent variables are 31 factors from the questionnaire.Multinomial Logistic and Ordinal regression analysis were performed on the 19 factors that were preliminarily screened out by the correlation analysis and were significant at the 0.05 level.The significant influencing factors were further screened and an estimation model for the application of electric heating in villages and towns was constructed.The factors that are significantly related to the application of electric heating in villages and towns are: whether there are elderly people,family annual income,residential area,heating area,residents’ behavior and energy-saving habits,indoor time during heating period,building thermal division,heating season length,average heating temperature,heating operation mode,whether heating peak and valley electricity prices are implemented,whether there are power supply quality problems,coal(natural gas,fuelwood/straw)usage;421actual cases are compared to verify the estimation capabilities of the two models,and the two models are in the estimation capabilities of the three categories of dependent variables have their own advantages,and the overall estimation accuracy rates are 83.1% and 84.1% respectively.Based on the aforementioned suitability conditions,combined with the frequency statistical results that represent user wishes,correlation analysis results and industry standards,from the six dimensions of technology,economy,comfort,practicability,environmental protection and safety,a total of 29 indicators are used to evaluate the suitability of direct electrical heating in villages and towns.The relative importance of the indicators is determined by the Delphi expert scoring method,the subjective and objective analytic hierarchy process-entropy method is used to calculate the index weight coefficient,the 1-9 scoring method is used to assign the value of each division level of the index,and the comprehensive suitability(good,medium,poor)evaluation based on the comprehensive index method.According to the electric heating application estimation model and evaluation system,a software for evaluating the suitability of direct electrical heating in villages and towns with functions of electric heating application forecasting,economic calculation,sub-item evaluation and comprehensive evaluation is developed.The software was used to conduct direct electrical heating equipment selection and suitability evaluation of 5 rural residential buildings.Based on the evaluation results,targeted policy suggestions to improve the suitability of electric heating in villages and towns were put forward.