Because of popular demand, and because I want to know, I'll be comparing a few different stoves. So far the models will include the Peak1, Esbit, tuna can stove, Esbit Army stove, can stove, and dryer vent can stoves.
A great source of homemade stove designs are found on Wings homemade stove archives.
All stoves will be evaluated in the following areas:
2. Fuel type
4. Set up time
5. Boil time, using two cups water in the same titanium pot (except for Army Esbit stove). This is a semi-boil, characterized by some bubbles forming at the bottom and coming up, but not a rolling boil. This starts at 175 degrees
6. True Boil as determined by thermometer or thermocouple and multimeter. This is when there is a constant rise of bubbles. 212.5 degrees at sea level.
7. Burn out time at high
8. Simmer times
9. Fuel efficiency, based on a standard cooking schedule of 2 hot meals per day made with 1 pint of water boiled at each meal.
10. Durability and ease of repair. 10 = tough as nails, 1 = fragile and not worth taking.
A rating system to decide which is best will not be done, that is for the hiker to decide. A Peak 1 may be better for someone that needs to fix big meals and melt snow, and Esbit may be better for a slack packer that doesn't want fuel bottles to worry about, and an alcohol may be the best for normal solo hiking. We will see.
* A true boil could not be achieved even at this weight of fuel.
For Weight over time comparison chart, go here.
More scientific tests of the Pepsi Can Stove and the Cat Stove.
***Note - I have had to modify this report on August 31, 2002. I used some incorrect data on volume and weight of alcohol in the initial report and have gone back through to fix this***
After reading the article at Thru-Hiker.com
comparing the Triangia alcohol stove to the Snowpeak and Gaz canister stoves, I
knew that a poor performer was used to test against the canister stoves. So I
volunteered to test my Cat Stove to show what a better performance stove could
do. As a comparison I also tested the Pepsi can stove.
The test really opened my eyes to the performance of my stove. I honestly thought that I was achieving a boil when bubbles formed and floated up to the top of my water. Now I have a more objective opinion of my stove's performance.
Instructions for the cat stove can be found at: http://www.hike.f2s.com/gear/homemade/rrstove.htm
Instruction for the Pepsi Can can be found at: http://www.pcthiker.com/pages/gear/pepsistove.html
2 cups of water at room temperature – 75 degrees.
Pot used is a Snow Peak 720ml titanium pot without lid.
Both stoves used the same windscreen and hardware cloth pot stand.
Alcohol was tested in 6 ml increments, starting at 12 ml
Each amount was double checked using a scale. The weight of one fluid
ounce of alcohol is .82 avoirdupois ounces.
Each Test was repeated three times, the average was used.
Starting time was when the stove was lit.
Stoves were allowed to completely cool between tests.
Barometric pressure here was 30.15, the boiling point was determined to
be 212.43 degrees.
Altitude is 90 meters above
Thermometer used is an Ecko deep fat fryer thermometer, probe was ¼”
below water surface using a camera tripod.
Air temperature was 75 degrees with the stove fan running to simulate a
13. Scale used was a Royal EX3.
Tested weight: 1.8 ounces with stand and wind
Tested weight: 1.6
ounces with stand and screen.
Bubbles forming isn't a good indication of boil, this starts at about
175*. Although the water at the pot surface may be at a boil, the water isn't
necessarily very hot throughout.
The more the alcohol used, the longer it takes to vaporize completely,
thus longer times to each temperature at each successive fluid level test.
the top of the water temperature didn't normally reach 212 degrees, the pot was
definitely at a roiling boil by 200 degrees.
The Cat Stove outperforms the Pepsi at the lower end of fuel consumption
in the area of heat achieved and time to achieve it.
5. Although the Cat Stove reaches boil faster, the Pepsi can stove maintains a high temperature for a longer period when using 1 fluid ounce or more of fuel. So it may take you twice as long to boil a dinner, but your food will also boil for twice as long using a Pepsi stove.
6. The Pepsi stove may eventually reach the higher temperatures of the Cat Stove with more fuel added, but I didn't find it necessary to test beyond 30 ml of alcohol. The Pepsi Stove maintained a very long roiling boil with 1 ounce of alcohol compared to the Cat Stove. If I had thought ahead, I would have recorded the number of seconds each stove maintained a temperature above 200 degrees.
So what would I choose?
If I was only wanting to boil water fast, and get by on the least amount of alcohol a day, then the Cat Stove will be a great choice. If you only need to boil 2 pints of water a day, then you could make it on 36 ml a day with the Cat Stove.
If I wanted to cook meals thoroughly and didn't mind slower heating times and larger fuel consumption, then the Pepsi stove is the way to go. It is lighter by .2 ounces, and you could boil 2 pints of water a day with 48 ml of alcohol per day. But you could boil you meals for a long time, ensuring they got completely cooked and were very hot as soon as they came off the stove.
I did some research and found that Propane has 21,600 BTUs per pound, Butane has 21,300 BTUs per pound, and Ethyl Alcohol has 13,160 BTUs per pound. This makes sense seeing that it takes about twice the alcohol in the cat stove to boil the same amount of water using a canister stove. A canister stove will need a lower amount of fuel weigh to boil the same amount of water as alcohol - winner is a butane/propane canister.
At the end of this test I started seriously looking for a canister stove, something like the MSR Pocket Rocket. I almost ordered one from REI the same day. Researching MSR IsoPro canisters, I found that a 8 ounce fuel canister actually weighs about 12.9 ounces, 4.9 ounces for an empty canister.
MSR Pocket Rocket
Base weight of a MSR is 3 ounces, but add another 4.9 ounces for the empty fuel canister, total of 7.9 ounces for a base. The standard MSR canister has 8oz of fuel. Since the MSR needs .3 ounces of fuel to boil a pint of water based on excellent research done by Russell Ray, I would need about .6 ounces of fuel a day. One canister would boil about 24-27 meals.
So, for a start weight of 15.9 ounces, you could go backpacking for 13.5 days using an MSR Pocket Rocket.
A Cat Stove with a base weight of 1.8 ounces with a 20oz soda bottle would have a base weight of 2.7 ounces. To boil two pints of water a day, you would need 36 ml of alcohol, weighing 1.0 ounces per day. For 13.5 days, you would need 486 ml of fuel weighing 13.5 ounces.
So for a start weight of 16.2 ounces you could go backpacking for 13.5 days using a Cat Stove.
A Pepsi stove with a base of 1.6 ounces with a 32 ounce water bottle for fuel, would have a base of 3.1 ounces. To boil two pints of water a day, you would need 48 ml of alcohol, weighing 1.3 ounces per day, for 13.5 days, you would need 648 ml of fuel weighing 17.6 ounces.
So for a start weight of 20.7 ounces you could go backpacking for 13.5 days using a Pepsi Stove.
So, I figured for $35 I was saving .3 ounces of pack weight to replace my Cat Stove with a MSR Pocket Rocket.
But then I started thinking about how I really pack, weight efficiency after the first day, price efficiency, and fuel availability.
1. How I really pack: For starters, I usually only hike 4 to 5 day sections even on a long hike, carrying just enough food to get me to each re-supply, and filling up whatever container I use for fuel at each stop when possible. Lately it is a 12 ounce water bottle weighing .6 ounces. My total stove + fuel + fuel bottle weight is only 11.9 ounces, less than a full MSR fuel canister. And it can take me 8 days to use up that much fuel - with 1 to 2 re-supply stops to look for more fuel.
2. Weight efficiency: Back to the MSR base weight vs. the Cat Stove base weight. If I compare the start weight at the beginning of 2 week hike, the MSR is 2.3 ounces lighter. But as the hike progresses, the Cat Stove user ends up carrying lower and lower amounts until the MSR stove user is carrying about 5.5 ounces more weight. The Pepsi stove starts high and stays high until the very end of a trip.
Red = Worst Performer
Yellow = Middle Performer
Green = Best Performer
3. Cost efficiency: My Cat stove costs about $6 to build, and that is a high estimate because of hardware cloth coming in such huge rolls. A realistic estimate is $2.50 to build at home if you use a coat hanger as a pot stand. That beats the base cost of the Pocket Rocket by $32.50. If you were to go buy a really expensive model like the Primus Titanium model, you save about $122.50. Soda cans can be even cheaper.
Fuel for the Canister models is about $5 for a canister large enough for 2 weeks camping - and is about the normal size you will find. I have bought 12oz bottles of alcohol for 98 cents, and 32 ounce cans for less than $3. So fuel is also cheaper.
4. Fuel availability: From my experience, alcohol is about #2 behind white gas when comparing to availability on the trail at re-supply stores. But you can also find alcohol at auto parts stores, quickie marts, hardware stores, and big chain stores like Wal-Mart and K-Mart. Canisters are not as easy to find in my experience.
If the base weight of the canister could be reduced to about 3 ounces then I would be very interested in switching to a canister stove. At 3 ounces, the overall weight efficiency for a 2 week trip would shift by a small fraction to the canister stove. But until they figure out how to make a 3 ounce or less fuel canister, the Cat Stove still has the advantage, but barely.
For sections shorter than 14 days, the canister weight would have to drop dramatically for the weight difference to be worth it. If a canister would weigh 2 ounces empty, then the Canister would rule even down to 8 day sections.
So, I think I'm going to buy a MSR Pocket Rocket. The performance as I've seen it is so close, it is worth a try. I've been doing some research, and the GAZ 270 gram cartridge is supposed to weigh 9 ounces, and has 7.8 ounces of fuel. If this is true and it works with the Pocket Rocket, then It definitely meets the above criteria. I'll test it for myself and decide.