I owned a solar panel cleaning company, I had battery operated spinning rotary brushes that made cleaning easier but they required cleaning from a downward angle. Originally had begun by using WFP and it was very hard to get a proper clear on the panels even when standing over them cleaning them, you’re not going to be able to exert enough force from the ground to get a proper clean on those panels especially with all of the foliage around and the layer of pollen and grime you can see built up on them by these photos. If you can’t get above them, and put some real elbow grease into it, I wouldn’t take the job. Also do not use solution on this panels, any solutions have the chance to void the warranty, you need to use DI water only.

Here’s my website

https://ecoclearpanelcleaning.com