they run better when they are cold, for instance someone developed white solar panel prototypes that heat less from the sun. Its just a circuit where the increase in temp makes more ESR
So you could water cool them, but usually the pump electricity and plumbing makes this non economical. Passive cooling with wicking action near water increases efficiency but water evaporates, meaning you are wasting fresh water. Salt water will corrode/cake up stuff and its very difficult to use. the wick is appealing because no pump or plumbing, and if you did it to sea water, I guess you would actually get more rain and replenish fresh water maybe, but water vapor is also a green house gas I think (need to explore ramifications), and it would depend on where it rains. I think its dismal and very situational unless you figure out a good way to use salt water to cool panels.
dip a rag in salt water and let it out to dry, you get a nasty POS at the end