Research On The Data Acquisition For Urban Building Energy Modeling

Urban building energy modeling(UBEM)is significant for constructing green and low-carbon cities.As the foundation of the UBEM,data has many problems to be solved,such as difficulty in obtaining geometric data and determining the randomness of occupancy behavior and equipment operation,as well as ignoring the heterogeneity of thermal parameters of construction assemblies and technical parameters of HVAC systems.Through multidisciplinary intersection,this paper systematically carried out the research on the data acquisition for the UBEM.The main contents are as follows:The existing and potential methods of obtaining geometric data,non-geometric data,weather data and actual energy consumption data for UBEM were summarized.In addition,the accuracy of the approaches,the availability and cost of the implemented data were also evaluated.Based on open-source data,an urban building 3D modeling method was proposed.Through the validation,it was found that the relative errors of 86%of building footprints,76%of building heights,and 75%of building fa(?)ade window-to-wall ratios were less than 10%.The method has the advantages of wide urban coverage,high availability of basic data,low cost,and fast and efficient implementation.Using the transportation accessibility and population level,the indoor hourly occupant density models for urban commercial buildings were established.The validation results indicate that the R~2of the indoor hourly occupant density models constructed for 75%of case buildings and 67%of test buildings was greater than 0.5.The approach has the advantages of being dynamic,fast,as well as relatively accurate.Based on the k-means and random forest classification,an approach for predicting the thermal parameters of construction assemblies of urban buildings was developed.Through the testing,it was found that the R~2 of the prediction of the thermal parameters of construction assemblies was greater than 0.6.The approach can effectively reflect the heterogeneity of the thermal parameters of construction assemblies of urban buildings and conduct fast and relatively accurate prediction on the values.To predict the composition of HVAC systems and their COPs in urban buildings,the“three-step prediction approach”was proposed.The prediction accuracy of the composition of HVAC systems was 78%and the R~2 of the COP prediction could reach 0.9 in the testing sets;and the mean absolute percentage error of the COP prediction was less than 10%in the case study.The approach can efficiently reflect the heterogeneity of HVAC systems and predict the COPs fast and accurately.In this paper,the summary and evaluation of data acquisition approaches for the UBEM can help researchers select suitable data acquisition approaches and thus improve the accuracy of the UBEM,and the four original researches are beneficial to improving data acquisition theories and providing new ideas for UBEM studies.