Greetings & Welcome!
Winters in the frozen North can definitely be challenging. I’ve spent many winters working outside in -60°f temps while living on wheels. Having enough heat is really the ONLY thing that works. The value of insulation in vehicles is highly questionable, but the values of good heating and cooling is well established.
Electric heat really won’t cut it even if you have shore power. Even a 1500 watt electric heater is only 5,100 BTU’s. At +50°f that’s great, but below that not so much. So some type of fuel powered heat is preferable, and if it doesn’t require electrical power of any kind, so much the better.
Below freezing we’re faced with unique challenges. I really never want my interior to drop below freezing, so that means running heat 24/7. For me there’s two different trains of thought on this, one is I don’t want everything inside freezing, and two, the colder it is inside the longer it takes to warm it up. You don’t want to get in your van and have to wait for many hours for it to warm up enough to be comfortable. It doesn’t take much heat to maintain the temperature, even without insulation, but raising the temperature is a whole different story.
I have one 23k BTU kerosene heater that also be cooked on, two 12k BTU kerosene heater/cookers, and two 8k BTU kerosene lamps. All of these will also burn diesel if needed. Once the van is comfortable, 3-5k BTU can maintain it, but if it’s below freezing when I get in, I’m cranking all of them up on high to raise the temps as quickly as possible.
So I have a little over 60k BTU available if I need it, and none of them require any power. Now, heat rises, and we’re down lower, so I have a heat powered wood stove fan that I’ll put on top of one of the heaters, to circulate the air, and keep the temperature consistent, from the floor to the ceiling. This combination works really well for me, and when I had a larger motorhome, I just added an additional 23k BTU kerosene heater to keep it comfortable.
You will want a carbon monoxide detector and you must provide outside ventilation to replace the oxygen being burned by the heaters.
For sleeping, working, or lounging inside, 12v or USB powered heating/cooling thermostat controlled blankets and seat cushions are hard to beat. For outside, or even inside, USB powered clothing can really make a difference too. The biggest problem with these is that require power, and you have to have a way to replace the power they use, and batteries don’t perform as well in the cold.
Can we do it? Absolutely, but your level of comfort and possibly your life depend on reliable equipment, plus you should always have backup plans if things aren’t going well. Even multiple layers of clothing can only go so far. Both cold and heat can be deadly, please don’t gamble with your life.
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