Reddit mentions of SoftHeat by Perfect Fit | Luxury Micro-Fleece Low-Voltage Electric Heated Blanket (Queen, Natural)

1. This looks like way overkill to me. It's designed to heat up an entire room, some 800 - 1400 ft^3. A teardrop is going to be way less than 200 ft^3. More like 90 for an interior than is 6'x5'x3'. Remember also that you are a heater. A human body at rest generates about 250 BTUs / hr. So how much heating do you need? Take the 6,000 BTU heater you linked, which is able to heat a 10x12x8 room. The volume of the teardrop is 0.075 as much as the room, so you'll need roughly 0.075 as much heat. If we accept 6,000 BTUs as necessary for the room, then the teardrop will require about 450 BTUs. But remember that your body generates 250 at rest. And if there's two of you in the teardrop, you're generating about 500 BTUs of heat, which exceeds the capabilities of the heater! So you really just need a little heat boost to take the edge off the cold before you get in the trailer (say in the evenings), and your own body heat should keep things cozy the rest of the night.
   
   
2. This is a natural gas heater. Will you be carrying NG?
   
   Consider a very small electric heater. You shouldn't need to use it a lot, and a very small amount of electricity should go a long way here. Couple it with a marine battery and it should last you for days, if you don't leave it on when it's not needed.
   
   Edit: It strikes me that a decent electric blanket would be an awesome solution. It's exactly the right size, puts out a good amount of heat for that amount of space, and they come in both AC and DC varieties. Just turn it on half an hour before you plan to go to bed, and I bet your trailer will be toasty warm by the time you're ready for it.
   
   Edit 2: For example, this Queen sized electric blanket produces about 560 BTUs/hr, takes about 15 minutes to warm up, and has an auto shutoff feature.

I first started vandwelling in the dead of New England winter - our first night in the van was 15 degrees F! (-9 C). A couple of things that I found helpful to make it more comfortable (until we were able to drive South to warmer weather):

• layers - you can always add more blankets. The trick is making sure that you aren't TOO warm (because sweating while you sleep in the cold will make it much, much worse)
  
• low-voltage (DC) electric blanket - I bought this one and it's worked super well for me throughout the years. Even on the coldest nights I would never need to turn it on any higher than 3/10, and the power use was absolutely minimal. With 200W of solar and 200Ah of battery (along with a 12v fridge running constantly and an inverter charging our electronics) we never even really noticed the power draw from the blanket.
  
  
• VENTILATE - the shitty truth is that unless you properly ventilate your van, every solid surface will collect condensation as you sleep that will either a) freeze before morning, assuming it's cold enough, or b) begin the molding process. Both of these are NOT fun to deal with. The absolute best way to deal with this is to install a roof-mounted vent/fan combo (the 'Fan-tastic Vent' or 'MaxxAir vent' are often recommended). If you don't feel like sawing through the roof of your vehicle, your other option is to open as many windows as you can manage every night. Our rig has screened sliding windows in the back that we would open no matter the weather. We also bought a tiny usb-powered 5v fan from Walmart to improve airflow a little bit. If we didn't have the windows open in the cold, the inside of our windshield froze over. Not fun.
  
  

Anyone ever rig one of these up?