...forty below is just fine, as long as you are suitably dressed, aware and thinking straight.
As for a fuel in those conditions, what's the issue? Go with white gas or kerosene.....Not as superbly convenient as a canister stove, but it will get the job done. Again, you must know what you are doing, but that is true in most of life's situations.
The issues for gas vs. liquid fuel in extreme cold are in general two fold:
1. Mechanical reliability
2. The dangers of priming when tent bound.
I recently read of an Arctic (Antarctic?) expedition that was using a liquid fueled stove. They brought three pumps for the one stove. Two out of the three pumps failed. They made it, but had that last pump failed, they would have been in a world of hurt. The problem? The "O" ring that seals the fuel line to the pump got so cold that it no longer sealed properly. If you want to talk about danger, try lighting a white gas stove that is sitting in a puddle of its own fuel.
Generally, gas stoves have greater mechanical reliability than liquid fueled stoves.
Gas stoves don't require priming. When it's -40 and there's a howling gale out, the only reasonable place is in your tent. You live there for 24 hours a day. You cook in your tent. Dangerous? Of course. But it's even more dangerous to open that door. Now, go ahead. Prime your liquid fueled stove. In your tent. And you were saying refilling gas canisters is dangerous?
The dangers of refilling are real, but put the dangers into perspective. Working with liquid fueled stove is as or more dangerous.
HJ
Previous Topic
Index
