I am in quite the dilema. I can finally get a greenhouse and a fairly large one as well. however I domt have a gas hookup and the only electric heater I can find is $1500!!!! I need one that is around 60,000 - 63,000 BTU. now I am needing one quite a bit cheaper and more efficent would be great. I was thinking of using a wood burning stove we used to use before we moved and then just use the heater for when im gone and times I can't keep the stove lit. I realize that they get very warm but I will try and not get it as warm and I will make sure and keep the humidity high. but what should I do about the electric heater. it needs to be able to kee the greenhouse around 50 degrees for about a week at a time in case I go on vacation. the greenhouse will be a quanset, plastic covered (6 mill) one layer, 30' x 18'. Hope you can help. thanks so very much in advance.