Unless there's someone in the pool, the solar cover is always on.
Being a smaller pool, I'm noticing evaporation (I see no leaks) of water since we've been in the 90's and my pool is in direct sunlight for all of the day.
13' X 39" Metal Framed AGP with an Intex 1600 gph pump, 14" sand filter and SWCG. Have to start somewhere....