MyHEAT — Solar • How It Works

Solar Potential Maps

This solar potential map provides estimates of the amount of power that may be generated by installing solar panels on a particular building. Citizens are encouraged to use the links and buttons provided on the map to learn more about solar providers and the financial incentives currently being offered to install solar panels.
These estimates are provided solely for informational purposes. To obtain an accurate assessment of a building's solar potential, you must have a qualified solar installer complete a detailed site analysis. In many cases, the solar potential provided on this map will be a single value for the whole building; a solar installer can also provide information for a smaller section of a building's roof.
In using the solar potential map, you expressly agree that you use it solely at your own risk and that the City of Edmonton is not liable to you for any damages whatsoever including any direct, indirect, incidental, consequential, special or other damages resulting from your use of the solar potential map.

How It Works

MyHEAT's solar potential map displays the amount of energy, in kilowatt-hours, that can potentially be generated each year when solar panels are installed on the rooftop of a building in Edmonton. The solar potential for each roof displayed on the map is estimated by:

1) Calculating the Sun Exposure

Solar irradiation (i.e., sun exposure) used in the model considers global irradiation - a combination of beam, diffuse, and reflected radiations received from the sun. When calculating the sun exposure, the model takes several parameters into account including the:
1. geographic location of the study area 2. elevation of buildings and objects on their roofs 3. elevation of the area surrounding buildings such as trees and neighbouring buildings 4. slope and aspect of roof surfaces on buildings
Light detection and ranging (LiDAR) data is used to determine the elevation-related information. This information used to identify shadows and obstructions, and the surface incline with respect to sunrays. By using a higher resolution of LiDAR data in the model simulation, MyHEAT can provide more accurate solar potential information.

2) Finding the Optimal Panel Location

MyHEAT determines the optimal location of solar panels by creating a grid of hypothetical panels over the entire roof. This starts with a single panel, with the parameters included in Table 1, positioned with the same orientation as the roof. Panels are then added through a recursive traversal, meaning that every location is filled on the roof's surface. Finally, the panels that do not entirely fit on the roof are removed.
Cells within the grid are then selected to be used in the potential energy generation calculation. These cells are selected using the following measures:
1. slope of the panel 2. flatness of the roof at the location of the panel 3. annual generation
These constraints help to ensure that installing a potential panel, with specifications in Table 1, and location is feasible.

3) Calculating the Annual Energy Generation

The annual energy generation potential for each building is calculated by first determining the generation potential for each hypothetical panel. This is calculated using the:
1. average daily irradiation per unit area 2. area of the panel 3. average number of sunny days in a year for the study area 4. efficiency of panel
The total annual generation for a roof is then obtained by combining the generation of all selected panels of a roof and is presented in kilowatt-hours (kWh).

Table 1 shows the parameters and their assumed values used in this simulation.

Parameter Value
Panel dimensions 1.65m × 0.992m
Number of sunny days (Edmonton) 321 per year
Maximum panel slope 60°
Panel efficiency 15.3%
DC to AC derate factor 0.85
Minimum annual generation of panel (DC) 240kWh
Table 1: Assumptions used in the simulation

Data Coverage

The solar potential map currently shows buildings from 2013 based on the footprint provided through the City of Edmonton’s Open Data Catalogue. Any changes made to a property after this date will not be reflected in the existing map.

Missing or Incomplete Data

Solar panel placement and related stats cannot be calculated for some buildings. This could be due to several factors, including a) significant amount of shadow on the roof, b) unsuitable slope and aspect of the roof, c) minimum annual generation required for a panel, and more. See Table 1 for reference.


If you would like to provide feedback, or believe there to be an error with the solar potential for a building included on the map, please contact us.