Thank you for playing - yes I will investigate the difficulty spike.
you get 7 power as the base solar gives 3 and its gets 1 for each adjacent panel +2 in this case, then each of the other panels gets plus +1 for the new solar panel that is adjacent to them +1 for each of them - 2 in this case. This gives you 3 + 2 + 1 + 1. which is the 7. Hopefully this makes more sense.
Yes grid removal has been the number 1 asked for feature - and I agree that the game would be better with it