A fellow veteran cruiser, Elizabeth Randall, told Sherine that she washes and cleans her panels everyday. Of course, I’ve always been curious about how much it really impacts the panels themselves looking at my panels on top of my two prior homes in San Jose, CA. They get filthy! But of course, in no way am I going up on the room to clean them…but I suspect folks do.
So, I decided to find out. I woke up and checked solar production. While this far from a comprehensive test, I thought I’d report it anyways. If I were to do this right, I’d track solar production over a week or so doing nothing and then track it cleaning the panels. In any case, I think it’s good information.
While One has 4 410W Sunpower Panels run into two MPPT controllers. One for Port and one for Starboard. At ~0900, While One is facing pretty much north due to the strong 20kt winds. I calculated the panels were producing about 298W. I cleaned all the panels and production seemed to increase to about 355W or possibly more. Moving the boom to Port so that it didn’t put a shadow across the panels, production increased to over 500W.
So essentially, cleaning the panels, which were really dirty by the way, produced about 20% more power.
Despite having 1600W of Solar, I can tell you that it hasn’t been enough to completely compensate for our power needs. Granted, we’re not trying to conserve. Yeah, we turn stuff off when we can but the inverter is running 24-7 and we’re powering several computers, Starlink, two freezers and two refrigerators. We generally run the generator when we make water. In any case, despite still running the generator about 6 hours this week, we went from nearly 70% state of charge (SOC) to about 32% SOC between Monday and Saturday morning.
I think my next improvement will be to install a higher current charger from the generator. At present, we only have about 80A capacity to charge our 1320Ah Li Ion battery bank. This would take about 18 hours (likely more) to charge to full. I estimate about 0.5 gallons/hour to run the generator at light loads (which is bad for the engine) so we’re talking 9 gallons or about $45 with $5.00/gallon diesel. Yikes!
Anyways, we can clearly do more to save water and power but “Happy Wife is a Happy Life”.
