Construction of low-cost models oriented to obtain the intra-urban solar potential in intermediates cities

Abstract

Currently, cities grow through dispersion and concentration processes, representing different problems associated with achieving urban sustainability goals. One of these aspects is the availability of incorporating renewable energy systems in other urban sectors, which is different for each case study. Indeed, any city pursuing sustainable development objectives must have methodologies to evaluate the relationship between its urban morphologies and sunlight. However, cities in developing countries do not have the economic and/or technical availability to access high-resolution methodologies such as LiDAR or large urban computer models for solar simulation or access to Google Project SunRoof. This work develops a low-cost methodology for constructing explanatory/predictive models oriented to identifying intra-urban solar potential in intermediate cities of developing countries. For this purpose, a representative sample of urban blocks is selected, and the incident solar radiation on their surfaces is simulated with DesignBuilder. For each one, we calculate several sunshine indicators and associate them with census variables that characterize their urban morphology. Subsequently, statistical models are built to describe two indicators (kWh/year*dwelling y kWh/year*m2) from census variables, which are available for all the census units that conform the city. The built models have an R2 of 0.87 and 0.70, respectively, and for each of them, two key products are obtained: a map of intra-urban solar potential; and a mathematical expression to calculate the future solar potential of a given urban sector.