We went back to OddBods for cleaning our solar panels, which were not only grubby but growing lichen. (With solar panel systems like ours, generation is only as good as the performance of the worst panel.) Lichen are difficult to spot when the panels are wet after cleaning, and, after Ben left and when the panels had dried, I could see that there were still some lichen patches left. I emailed OddBods,and Ben returned the next day. and removed the residual lichen patches. Generation now in bright January sunshine is comparable with January performance when first installed more than 10 years ago.