Yes, you can design systems using bifacial modules using SolarDesignTool, however each backside irradiance percentage increment for a given module will be listed separately. 

Search for the module in the system builder and select the model with the applicable backside irradiance percentage for your roof surface type and installation scenario. At this time the app is unable to automatically calculate the backside irradiance percentage, so you'll need to determine this independently.

If you don't see the module you're looking for, send us a message and we can typically add it to our database within about 24 hours.