I'm finishing an 8 x 12' lean-to style prefab wood shed that I have been modding into a chicken coop, but I need to actively ventilate it because I found out it gets HOT. I've got a large (30x30")solar panel and a deep cell marine battery already installed for the poultry door (overkill I know) but can I also hook up a 12" exhaust fan to the battery without completely draining it every day? What exhaust fan is recommended? Price is not a big factor but I'd prefer an easy, effective and low-maintenance solution. Thanks!!! LINKS TO ACTUAL PRODUCTS YOU KNOW AND WOULD BUY ARE RECOMMENDED!