This is my first summer with my updated solar panels (66% surface coverage area) including a solar controller (old panels came down with the old roof last year), so for the last 6-8 weeks I have been running my solar panels in night time cooling mode to attempt to maintain my desired water temperature of around 84 - 85 degrees, so far with fairly good results. Traditionally by mid August without use of cooling techniques my water would be in the mid 90's , but by setting my solar controller to a cooling goal temperature of 82, I have achieved the above mentioned 84-85 degree afternoon water temperature. I am somewhat surprised by these results since for the last several weeks we have been experiencing average highs in the upper 90's (almost never less than 95) that only dip down to the mid - upper 70's in the early morning hours with 70-80% relative humidity at night. (temperature at midnight is often above 80 degrees) I suspect one key helper has been the solar controller with opportunistic cooling when we have short lived afternoon thermal thunderstorms which have been in fairly elusive this year, as these storms can cause rapid localized cooling and relatively cold rain water, even occasional hail during the peak of the summer months.
Now down to the question part, how many of you also use your solar panels for pool cooling during the summer months, do you have an automatic controller, and how effective is it for you?