Irradiance Express

Irradiance Express recipe for Pollination

This recipe calculate the solar irradiance (W/m2) for each timestep provided in the wea file. Nigh-time hours are filtered before running the simulation. To match the results for each hours see the list of hours in sun-up-hours.txt.

Limitations

This recipe uses Radiance's gendaymtx to generate the sky. "Gendaymtx takes a weather tape as input and produces a matrix of sky patch values using the Perez all weather model". "If there is a sun in the description, gendaymtx will include its contribution in the four nearest sky patches, distributing energy according to centroid proximity". This means that the value of direct sun is diffused between these patches. This approximation is fine for studies such as cumulative radiation or for outdoor studies where the amount of exact direct radiation is not critical. For accurate accounting of direct sun see the Irradiance recipe.