Dont be stupid.
You cannot clean 4 solar panels a minute. Minute after minute after minute. Unless theyre all within a 2 yard distance from you, are reasonably clean to start with and extremely easily accessible, i.e. on the ground.
These broad, sweeping statements on here are about as useful as a chocolate fireguard.
4 panels a minute, 8 hours a day, 75p each, that works out at £1440.00. a day. Lightweight.
There, ive said now.....
Some things are better left unsaid.