Yes, on a boat you have to wash the panels periodically to get rid of salt and bird poop. The latter can be a surprisingly big problem. Southeast of Galapagos

Yes, on a boat you have to wash the panels periodically to get rid of salt and bird poop. The latter can be a surprisingly big problem. Southeast of Galapagos we had a booby sit on our spreader for a day, and it managed to cover our two 100Wp panels in the bow almost completely.