The primary purpose of this Web Map is to present accurate estimations of the monthly and annual solar insolation for locations throughout British Columbia. This dataset was generated using an empirical solar heat gain calculation that assumes clear skies. The data was generated by applying my python module to geographical points. The points are from DataBC's BC Geographical Names layer. The topographical information is from HectaresBC's Slope & Aspect raster data layers.

The insolation data in the web map can be used to conduct feasibility analysis for solar photo-voltaic or hot-water potential. It could also be used as a tool for assessing the growing potential of a site.

Map Instructions

  1. Navigate the location of interest (manually, using the location service,
    or using the Find! Tool tool).
  2. Choose your Regional District to display Solar Insolation points for
    geographical locations in your area.
  3. Choose RDs
  4. Click on points nearest to your location to display monthly and total annual solar insolation.
  5. Select Points
Note: Choose points that have a similar slope and aspect to your desired location.
Recommended to average a few points in your area for a closer approximation.


The solar insolation values presented in the BC Solar Map is empirical.
It was calculated using the American Society of Heating, Refrigeration,
and Air-Conditioning Engineers (ASHRAE) building heat gain calculations.
As such the following assumptions and limitations should be kept in mind.

  1. Assumes clear skies and thus represent the maximum possible insolation.
  2. Does not take into account hill shading ∴ south aspect points that are shaded
    will be lower than reported due to reduced photoperiod.
  3. Similarly the model does not take into account shading from trees, buildings, or
    other features.