I am going on the silloutte trail(Killarney,ON.) in mid september for 8 days .I will be using a snow peak gigi power stove to mainly boil water in my snowpeak 700 pot for 2 hot (just add water) meals a day .My question is aprox. how many 8 oz msr isopro fuel canisters would you recommend?
Thanks
Marcinont.

I use about an ounce of fuel per day or a bit less. In the morning, I boil 12 oz of water for coffee, 8 oz for tea and 8 oz for hot chocolate. At dinner, I boil about a cup for hot soup and about a pint for re-hydrating my dinner.

Often I will also warm a small amount of water to clean the residue from my MSR Titan. I don't use freezer bags for cooking; on long trips, the weight adds up. Three of them weigh a bit over an ounce. I use Baggies (0.04 oz) and cook in my pot; the weight savings is, to me, worth the minor added work.

I am careful to shut the stove off when the water boils and never boil more than the exact amount of water I need for the purpose. I use a good wind screen but do not allow the canister to get hot.

There are two of us, so that changes the equation a bit, but we find that one 8 oz. fuel canister lasts us for just about a week. And like Pika. we don't cook things, we just rehydrate with boiling water, and we do that for oatmeal in the morning and a freeze dried dinner at night. And we turn the stove off as soon as the water boils...

It would appear you will be boiling approx 500 to 600 ml twice a day. Since you are unlikely to need to cook supper on the last day, that makes 15 meals. In my experience, this would require almost exactly one 8 oz. canister, but my stove use differs somewhat from what you describe; I tend to simmer my meal for a time after bringin the water to a boil.

If you are truly just bringing the water to a boil and shutting the stove off immediately then it seems very likely you can get away with one canister and save the weight of a second one.

Whether or not you use a windscreen can affect your rate of fuel use. Anything more than a very mild breeze will reduce your stove's efficiency, if you do not shield it. I do use a windscreen and recommend using one.

Since your scenario is approaching the borderline case, you may want to consider the weather conditions and how easily you could build a fire if adverse conditions came up. If bad weather (cold, wet) is a consideration, then having a cushion of some extra fuel can be helpful. Even then, I would say a second 8 oz. canister would be overkill. A 4 oz. backup should be plenty.

Edit: If you put a gun to my head and forced me to stop equivocating, I'd just say take one canister and live with the small chance of running out of fuel for your last day's meal.

I forgot to mention that if my fuel calculations are a bit on the close side, I will take along a CAT alcohol stove and a 4 oz bottle of alcohol fuel as a lightweight backup. If you take Everclear as fuel and your cartridge seems to be holding up, you can always make cocktails.

EDIT--Oops, I always do this--hit "reply" after the last post. This is really a reply to the Original Poster!

Test the stove outdoors at home. Weigh the canister first and record the weight. Put the amount of water you normally heat up for a meal in your pot. Be sure it's cold water; I use water that has been in my refrigerator. Do this on a day with some breeze if you can. Bring it to a boil. Then weigh the canister again. This will give you a pretty close approximation of how much fuel you will use per boil.

Check the label on your fuel canister; it should tell you the net weight (weight of fuel) and gross weight (weight of fuel plus the canister). A little division will tell you how many boils you will get out of a full canister. I always allow for an extra boil--I might want more hot tea if the weather gets really cold and nasty. I also want to allow for knocking the pot over at least once per long trip. On the other hand, if you're going to be where campfires are legal the last day or two of your trip, it's no big deal if you run out.

I boil only once a day (I eat a cold breakfast). If I take at least one non-cook meal, I can manage 8-9 days out of a small (4-oz.) MSR canister. I take a large one if I'm going to be fishing (at least hoping that I'll get a couple of chances to cook fish!). I wouldn't suggest anyone's trying that without testing for their own needs!

Great care needs to be taken when using a windscreen with a canister stove. Check frequently to be sure the canister isn't overheating. A bomb going off in your face would not be pretty! I have one that goes only 3/4 of the way around the pot, but I still check the cartridge frequently.

Since you haven't got experience on usage yet, I'd suggest that you take a large (8 oz.) canister, plus a second canister just in case.

After you have some experience with the usage, you'll have a better basis for making your own decisions about whether the second canister (or a smaller second canister) is necessary.

Some tips you may want to consider.
Most stoves will use about 30% less fuel to boil the same amount if used at about half power . (mostly because at full power the heat is lost up the sides)
A large bottom pot is more efficient than a narrow one.
You do mot need to get a roaring boil for tea/coffee/chocolate. When you see a few bubbles that is hot enough.
(that is if you do not need to purify your water)

Franco

m
I see you are a newbie, welcome. You may have a great deal of experience, but if you did you wouldn't be asking this question. Though your intent is to do minimal cooking, without experience at it, plus maybe you underestimate your need for hot drinks, and perhaps you should double your minimum at first to try it out. I drink coffee, so I have gone thorugh a cannister per day in warm weather alone.
Jim

Jim speaks the truth. That's a lot of coffee though jim.

Anyway, I would add that an 8-day trip with new gear is probably not the most advisable recommendation. I would suggest a 2-3 day (max) trip with the new stove to see how it works for you under real conditions. from there you will see how much *you* use for your meals and can then make an informed decision. Absent the shakedown trip, I concur with Jim... take double.

Pika

Are you cooking out of a bulk store of food? How do you set up those menus?

Steadman

This question is sort of like the ones asking how much water to carry or how much food to bring. All are very difficult to answer accurately due to the large number of variables.

The answer to your question depends on the ambient air temperature, the temperature of the water when you start, the volume of water your meals require, the wind speed (if any) when you heat the water, the boiling point for water at your altitude, the efficiency of your pot, and I'm sure I'm leaving out one or more.

If I had to give you an answer it would be three. But maybe you'll only need one. It is impossible for anyone here to tell you how much fuel you will consume. Better to have too much than not enough.