@LudvigNyman ,
Wow! I only put this in a week ago and already you’re starting to use it 
The current implementation on the H+ WEA object allows you to get the direct normal radiation and the diffuse horizontal radiation for both the original ASHRAE Clear Sky and the Tau model. The one thing that is missing on the implementation that is needed to create new EPWs is the ability to get global horizontal radiation from the direct and diffuse solar. I was planning to add a method on the WEA object this week to get this and, as soon as I add it, I’ll post a full example here showing how to create an EPW with a clear sky.