Amount of denatured alchohol for trip

Depends on the model of stove. Try setting up your stove in the harshest elements you can find, or run your stove with a fan blowing on it. Boil your water and multiply the amount you used times the number of meals to be prepared. Then add a ounce or two for spills, extra coffee, etc. Should get you close anyway.

I would be surprised is gas didn’t turn out to be lighter than alcohol over a trip of this duration. From my experience, using gas will be lighter when your trip is longer than three to four days (depending on how and what you cook).

http://www.bushwalking.org.au/FAQ/FAQ_Ultralightweight.htm#Stove explains this well.

If you do use the alcohol stove, I strongly recommend you try using the stove boiling water in the expected wind you will encounter to get a real guage for fuel use – there is no other answer.

I agree with Teresa but would add: Elevation, Ambient Air / Water Temperature as major factors in how well your stove will perform.

Thanks very much for all the helpful comments. Since I posted this, I found my notes from a 9 day Sierra trip I did about 6 years ago with the same homemade alcohol stove, and we used .75 liter of alcohol fuel on that trip. So maybe I’ll just bring the same amount. I know white gas would be more efficient, but I was pleasantly surprised how little fuel we used on that trip, which was mostly at 10-11k’. And my white gas stove weighs a pound…