Diesel heater for sure. Name brand if you can afford them, cheap Amazon chinese models for the rest of us. Between my son's and myself, we have 3 of them. We build our own enclosures and assemble ourselves vs. the self contained units on Amazon. That way we can control how bomb proof we make them. The first one we bought was less than $100 for a 5Kw unit. The last couple have been in the $120-$130 range for the entire kit. We purchase the heater kits that would be installed in campers and vans. Typically, everything you need is included. But like anything, you can customize to your hearts content. The fuel consumption is very economical. Our heaters on a low setting consume roughly 1-1.5 liters of diesel in 12 hours. We use these heaters in 12x12 and 12x14 canvas tents in MN and ND. The coldest we have run them was -44*F. Even at that temp, a medium setting would roast you out of the tent. Most nights, we run it in the morning while eating/getting ready (1-2 hours) and evenings after hunting (3-6 hours). The heater and fuel piece of the total package seems to be the easy part. The battery has always been the limiting factor. In the past, we have used deep cycle batteries as our power source. Running as described above, we could get 4-5 days use before the battery was getting "iffy". On a 10 day hunt, we would bring 2 batteries. We have experimented with solar but in our area there isn't much sunlight in the fall/winter to consistently make the solar work very well. This past year we have been experimenting with both purchased power packs made by Jackery and Schumacher. Also have purchased a 100aH battery and charger off Amazon. The LiPo type power boxes and batteries seem to be the direction we will be going. Basically get longer duration power in a much lighter package. I recently ran my heater on a low setting for 7 days straight on the 100aH battery setup and still had 40% charge when I shut if off. Using a 10 liter tank, I filled it twice with the tank being full when I started. So far, I am very impressed with the LiPo battery setup. The real test will be when it starts getting colder outside but the plan is to have the battery box with 100aH battery in the tent since its a sealed unit. For what we do, they can't be beat. It's basically like having a forced air furnace for your tent/camper/van/trailer. Another side note...when my buddy lost power for a couple days last winter in sub zero temps, we rigged up a diesel heater on the outside of his house running the heat tube in through his dryer vent. Disconnected the dryer hose, packed rags around the hose to seal it off, and ran the diesel heater wide open for 2 1/2 days to keep his house from freezing up. He has a smaller house, probably 1100 sq ft and it kept the inside temp in the high 40's. Was -10 to -20*F outside. He has since got his own setup. That my experience. Mileage may vary by user.......
