I can see how small efficiencies would matter a lot in that sitation.
When I had 6 100W panels and was trying to keep my laptop (and lights) running off that, then I did a lot more trying to keep them clean. If I was having to burn fuel for electricity, I'd certainly be trying a lot harder to squeeze what I can out the array.
Anyhow, good luck.
I likely am in a similar position. My hope is to get a cistern buried this year so I can have more than 40L of liquid water on hand at any given time... and then maybe even a shower :D Washing myself with a bucket is starting to lose its charm.
There is a lot that loses it's charm, lol. Started with an outside kitchen and shower, which was fine in the summer but in the winter when the wind blows and it takes 30 mins to heat a pot of coffee the charm wears thin, lol.
Good luck to you too!
It's fun to meet the basic challenges head on though, eh?