This map is based on 30+ years of solar data collected from 235 weather stations across Canada. (The grey points in the map)
It gives the annual energy yield in kWh of a 1 kWp PV solar system installed on a fixed rack set at the optimum tilt angle.
The results are corrected for the temperature and low irradiation (PV Modules are more efficient in low temperature and less efficient in low irradiation level)
A fixed system is not the most efficient mounting system (trackers are more efficient). But it is cheaper to install. The program calculated the optimum angle for a particular location, therefore, the map shows the maximum energy yield achievable by 1 kW modules on a fixed rack under real conditions of temperature and irradiation.