Search for "Mushe Cooker". People use them racing in extreme temperatures(-50C+).
I used alcohol stove down to -10C, but it takes too long to melt snow. In light winter weather you will need 20+ minutes to melt and boil little over 1L, and you will probably use around 60-90ml of alcohol, depending few factors. But if you need it just to boil water, it will work great.
Tips from my experience for cold weather:
- Use the stove that will bloom fast.
- Isolate stove from ground (aluminum foil and some foam pad).
- Use stove that has separate pot stand.
If your stove is touching the pot, pot cooling down stove becomes noticable, which will degrade the stove performance.
- Keep fuel in your pocket before putting it in stove (also stove if possible).