I built a frame for a solar panel (the one in the pictures is 30W) for dual-use at home. I bought it to carry it around while camping (to charge my phone and generally have some energy for LEDs etc). Since I will spend more time at home than on the road (sadly), I built this frame to mount it in a window (directing south). This way, I can use it to power my server and help me pay my bills :). Maybe it helps other to build something like this. I can unmount it within 10 seconds, but the window also opens with everything connected (only a bit, but usually that's enough).
Used some 3D-Printed connections, and M8 threaded rods since they are sturdy enough. Using some M3 screws and an aluminium L profile, I made a mount for the lower part of the window (there was a gap on the lower part of the window).