Actually, I'm probably wrong on the 15 minutes to cool. After a lap, my car sometimes didnt even reach 190 and the fan never came on, its just the hot lapping that heats it up. Between doing the run, then sitting in the lane waiting to run again it just ends up being a while. Thats where you can shut down, run your fan and electric water pump and cool down. I don't bother shutting down since it doesnt help me cool down anyways, at least in the staging lanes.
My fan is a Spal 16in fan. it wasnt that cheap, but no, it doesnt draw 20 amps.
I think that if I figure out my water circulation method and let it rest a tad between runs it will cool down nicely.