The PB we are leaning toward building our pool with said we only needed a 1.5 single speed motor. Since we want a simple 15x30 3.5' x 6' x 5' without any other features or spa it wasn't necessary to have a variable speed. I keep reading on the sight how variable speeds save on energy bills. Would the variable speed be of any help with our pool? Do we need the 1.5 hp or would the 1.0 hp work?