Estimating Sunlight?

[rbecker]

I've been playing around with Sketchup, and one thing I think should be doable which I haven't been able to find is estimating the amount of sunlight a spot gets in hours/day- assuming that the sketchup model has been geo-located and all objects which would block sunlight have been modeled. What would be really neat would be to have a query-tool like ability to click on a surface and get an estimate of sunlight hours per day, for summer and winter seasons. Does anyone know if such a thing exists?

[Gaieus]

There's 1001 bit shadows and sky ratio:
http://www.1001shadows.com/en/products.html

Maybe there are other tools, too, I have never needed them. It's a commercial plugin.