SteamyTea

Start reading: https://www.gov.uk/government/publications/electricity-market-reform-contracts-for-difference I think there are several different ways that a PV generation company can sell their produce, just a case of someone sitting down and working out the best contract to be on. If you take out the CO2 element, they are just like ordinary, small scale, producers and can enter the auctions when the price is right. So they may elect to just sell power for the morning and evening peaks in the summer and give power away the rest of the time. This, if there is enough solar being generated, will affect the market price. That is a risky game to play though as they may have to 'buy in' power when they cannot supply, and that will be very expensive as it is calling on the 'hot spinning reserves'

Have you really forked out nearly £50,000 before you actually start the real work?

I come from a production engineering background, I don't see that as a problem.

If you are using a lot of timber on site, and most houses seem to have more timber than anything else, why not buy a cheap, but adequate, planer thicknesser and save yourself a lot of time and hassle.