Hello, and please can I ask for comments. I'm thinking of (diy) installing a small ground mounted off-grid pv system, to help with dhw or for a little space heating. The important questions are probably the ones I don't even know to ask.

It's to have six panels of the common size, about 1.65m x 1m, arranged landscape, 2 wide x 3 deep, so overall about 3.3m wide x 3m deep. The site is rocky, a sort of amphitheatre, facing SW. I propose to make the frame of scaffold, with concrete flags and/or lintels as ballast weights.

There are some photos of the site and of a model of the frame, and more description of details at
https://www.flickr.com/photos/89810542@N02/sets/72157649544482805/

How long will scaffolding last, and is there a good way to stop the clips and tube going rusty?

The ground is difficult - at the back is very uneven solid rock, but it cleaves and tends to crack, and would need quite long fixings to be secure. I propose lintels for ballast, since they will rest on just a few points of rock. They will not be fixed, relying on the braced frame to prevent them sliding.

At the front the ground is very stony earth - a 30mm masonry drill will not push the stones out of the way, so I don't think it would be possible to hammer in spiral ground anchors. I can dig it with a pick. There is no access for machinery. So I propose a stack of two or three concrete flagstones at each side, part below ground level to hold them in place.

The four ballasts will be fixed to the front and back bottom tubes with 100mm wide x 6mm thick strip and 16mm threaded rod, all stainless steel.

The total panel area is about 10 sq m, and the total weight of the frame and ballast about 550kg, biased to the front. Exposure is moderate - the site is windy, but the installation is protected by trees and rising ground.

More questions about the electrical side but I'll stop there. Any suggestions will be welcomed, particularly about the frame and ballast. Please let me know if details are not clear.

Posted By: tonyIf you are in the UK you will need planning permission

It'd likely be permitted development in Scotland.

Thanks for comments all, some helpful pointers. I'll check on the planning permission. Galvanised steel will be cheaper than stainless. The small tree is dead so will be removed.