Cooling a barn

I am going to add a battery controlled thermostat to my barn. I have several 12 volt muffin fans for my horses that they love to stand by at night and it also keeps the flies away a bit. The problem is those fans really pull the juice. If I do not get out fast enough to turn off the fans it really can dog down the battery. The solution was created by my father in law who made a solar thermostat that can turn the fans off and on depending on the temp of the barn. Think about it, it can and will work. If you are interested just e-mail me at jrossini@rossini.com.