Okay, I get it. Many people do not use heat inside of their coops. That is fine and dandy. I also know that chickens can produce approximately 5 btu of heat themselves every hour. I will put Vaseline on their combs to prevent frostbite. I also plan on using the deep litter method, and providing cracked corn in the winter which will help keep their temperatures up. I will be keeping this by the roost, however above the ground high enough from the substrate. I will be consulting an electrician about wiring it, and using breakers to cut the power if there are problems. There will be fire alarms, and fire and bite proof wires. So please, do not say anything in the comments about the things I have already stated. You will just be tooting your own horn and wasting my time. Thanks in advance. Please do not provide alternative heating methods. I have looked into all of them. These are the ones I am selecting from, so lets please try to stay on topic. So, on to the real subject. I am considering using one of these three radiant heating elements to heat my coop. I will be using a thermocube 35-45 F which will tell the heating element to turn off and on. If you have experience in using other temperature heat cubes, I would be interested in hearing about that. Or, other ways that you set automatic temperature control switches. So, here is the real dillema. I am stuck about which of these products would work best. Does anyone have personal experience with any of these products? The place I live dips down to subzero temperatures a couple times per year, and I want to keep my chickens laying, and the eggs from not freezing as fast before I have time to get out there and grab them. I would rather have my hens and roosters focused on making babies instead of just struggling to stay warm. I am planning on installing this inside of an 8x4 well ventilated walk in coop. So, here are the options. https://www.amazon.com/Cozy-Products-CL-Radiant-Heater/dp/B00FRFFC4W/ref=pd_sbs_86_5?_encoding=UTF8&pd_rd_i=B00FRFFC4W&pd_rd_r=EPRD7SQJYF5TNBT25KQR&pd_rd_w=us4eF&pd_rd_wg=s4JeO&psc=1&refRID=EPRD7SQJYF5TNBT25KQR Only 150 watt heater. Many people are happy with this product using it in their coops according to amazon. It is recommended by the Chicken Chick. https://www.amazon.com/Cozy-Products-Chicken-Heater-Technology/dp/B01LX9K1JI/ref=sr_1_1?ie=UTF8&qid=1491987136&sr=8-1&keywords=coop+heater 200 watt designed for chickens $42 Look into sweeter heater for heating the coops. It says that it is energy efficient. This product is pretty good, and it comes in a size that is 11x40 yet only takes up 150 watts of electricity. The price for that one is $140. I like this one because of the space it covers. I am not sure whether or not I should mount it on the side, or let it hang from chains. I like the idea of letting it hang by chains, because I could better utilize how many chickens have access to it, by being on top, below, and on the sides of it. I would put a layer of something directly above it if the heat can rise above 100 F, which I am pretty sure will not happen in 20 F weather. However I do like the idea of a side wall mount because it would mean that I do not have as many chickens jumping on top of other chickens, or http://sweeterheater.com/ https://www.mypetchicken.com/catalo...Lt9ub29UB-z6BKHNhYjyko5L8OtnCN2XquRoC_xbw_wcB Here is more info on the sweeter heater. https://www.omegafields.com/blog/getting-started-right/ And more info on the sweeter heater. Does anyone have any advice about how long these products last over time? How about fluctuations in output? Has anybody experienced issues with any of these devices? I am most concerned about the Sweeter Heater because I can hardly find any reviews or relevant information about it. Does anyone know about how these products compare in the heat output they generate? Thank you for your time and for your wisdom!