Solar analysis for an urban context from GIS to block-scale evaluations

Global and national policies are increasingly addressing the reduction of greenhouse gases (GHG) emissions and the diffusion of renewable energy resources. Building efficiency and decarbonisation pathways are often supported by promoting the installation of solar energy sources. Urban solar assessments are hence extremely useful to identify favourable locations and sizing of photovoltaic (PV) installations. This research aims to estimate the solar PV potential for a city-dense context. The case study is the downtown area of Toronto (Canada). While most of previous studies look at only one scale, this work adopts a multi-scalar methodology to model PV potential within the main residential building archetypes within the selected location. Rooftop GIS-based analysis estimates up to 26% satisfied electricity consumption for detached houses, and 7% for apartment buildings through polycrystalline PV. A following optimisation performed with the tool URBANopt shows solar block-scale best configurations and profitable financially ones. PV panels with net-metering achieve from 18% up to 41% self-sufficiency. The two assessments confirm that local solar resources can reduce energy dependency on the grid and promote the feasibility of energy communities. This study demonstrates how energy tools from GIS to block-scale are critical to support local administrations in urban planning and PV plans.