agree with Doug on both points above.

I am cautious when using alcohol for fuel and ALWAYS put a lid on the container that is being boiled. It's too easy for the alcohol vapors to condense on cool metal and drip into your food/drink.

I have never used alcohol for anything serious - only demo projects at home - just to test the system. But I would be worried about alcohol as a true survival fuel. When you are seriously cold - you need real heat fast. I don't know how well that fuel system would work for -40 degrees, or for hypothermic situations.