Yes, it is heat energy from the heat transfer (transferred from your car's interior and your personal exterior to the coil outside) plus the work of the heat transfer process being put right in front of the radiator that makes the radiator get warmer air and work like it is a hotter day. Can I make a longer, more specific sentence?
More outside temp air is the best answer, and stop and go traffic on hot days is the only reason I might consider an electric fan conversion. You can get good airflow at 0 MPH and idle. That it might free up some power is not bad either, but for reliability, I like a thermal mechanical fan clutch most of the time.