I made the wedges under the solar panels by setting up a jig with two rails mounted on a plywood base. The wood portions are teak and the light gray portions are painted Divinycell foam core material.

I mounted the work piece so one side was tacked to the bottom base between the rails (held by small dots of hot melt glue) and the other side was tacked to a raised strip of wood (not as high as the rails). The angle of the piece was set to match the desired taper. The router was mounted to a heavy piece of acrylic as a base that would ride over the top spanning both of the rails, and a straight bit was used to trim the material level at the top. The router was at a fixed-depth and moved back and forth until the desired material was removed. Sanding smoothed out the marks between router passes. The hot melt glue dots are easily shaved flush with a knife or sanded off when you're done.

If that doesn't make sense, I'll take a photo of my jig (still have it) and post it.