(Updated 9/9/2016)

There has been a lot of discussion over the past few years over the actual efficiency of alcohol stoves. These stoves are ultra light, as low as 8 grams. When these first became all the rage, people were praising them for simplicity and weight. The talk more recently has shifted to efficiency. The fuel is about half as efficient (heat generated per weight) as the gold standard compressed butane/propane burner. The down side there is of course the weight of the steel cylinder, and inability to take only as much fuel as needed. They are only sold in 4oz, 8oz, and 16oz cans. Despite this, several articles have noted that there is a point (usually expressed as a number of days) where the average packed weight of the butane/propane setup is actually less than an alcohol setup. The numbers look good, and their method was sound. I took it, and ran with it. Got a super light titanium burner, and stocked up on 4oz cans in preparation for a month hiking the North Cascades.

I leave in 3 days. This week I’ve been packing my resupply boxes. 7 and 8 days in a USPS Large Priority Mail box. My initial thought was to send along a 4oz fuel can in each. Unfortunately, they can’t be sent Priority, as they have to go ground. Even more unfortunately, I waited too long to be able to ship USPS ground, and the post office doesn’t take kindly to FedEx and UPS packages coming “General Delivery”. So I started reconsidering my fuel options. The cities I know I’ll be stopping at may have fuel, or may not. They’ll most likely have the 8oz cans, but 4oz is more than enough for me for a week (14 days if I’m lucky). I know I can get alcohol! I can burn anything with a high enough concentration. Hardware stores have denatured alcohol. Gas stations have Heet. Liquor stores have everclear, or 151. Each fuel has pro and cons, but they will all boil water. Only backpacking stores carry backpacking fuel cans. The only thing I needed to find out was how much was needed. I tossed a bottle of water in the fridge, and headed out to pick up a bottle of Heet. I first tried 20 grams (yes by weight, easier than explaining to my wife why I’m using her measuring spoons with fuel line treatment). Turns out 20 grams was far too much to bring my 10 oz of water to a near boil (see Freezer Bag Cooking and Creamy Parmesan Ramen). 8 grams was about right. 1 tsp is about 4 grams of fuel. So I’ll bring 8 grams of fuel per day, for 10 days (I don’t mind the buffer, in case I spill a little fuel or heated water, or possibly even have to melt snow). That’s 80 grams of fuel, plus I’ll estimate 20 grams for the empty PET “water” bottle to store it (mark this clearly!), we’re at 100 grams. My 4 oz (much harder to source) fuel can is over 200 grams! I was surprised. Most articles had told me 3 or 4 days was the point where the two are even (average packed weight wise). Their mistake was the casual assumption how much water one needs to boil. Their calculations were 3 to 5 cups of water boiled daily. That’s as much as 4x the water I’m boiling, and I don’t need to simmer! I’d be pushing 3 weeks easily on 200 (180+20) grams alcohol.

 

UPDATE:

In real world conditions, this didn’t work out as well as I’d hoped. My bottle of fuel easily lasted a week, but not likely longer than 10 days. It was likely a combination of spillage, overfills. wind, and altitude. After my first week on the trail, I switched back to my butane/propane cylinder and never looked back. One of the major deciding factors was the ability to somewhat safely cook inside my tent (before you lecture me or cook in your tent, read “Can I Cook in My Tent?“). The alcohol stoves take a long time, the bugs were brutal, and I do not pack a chair. Ultimately the decision was simple. Being able to retire to my tent at the end of a 15-20 mile day made it one of the best gear choices I made. I considered deleting this post, but decided to leave it up as a learning experience. Things don’t always work out as you plan!