alcohol stove efficiency

[mauiarcher]

So I have been using canister stoves (jet boil, MSR, kovea, etc.) that I have been really happy with and no real desire to change. However, local conditions have forced me to explore alky stoves. I have made about a dozen (penny, can, AL beer bottle, etc.) and had thought they were all about the same...until I used a caldera cone. That stove that comes with it is about twice as efficient as my efforts thus far. In an effort to stand on the shoulders of others, what fuel sipping stoves have you come across? Thank you in advance.

[Gambit McCrae]

I guess my comment is more of my short story of transition
I had only ever used pocket rocket, screw on canister type stoves. Just as an effort to save weight, I transitioned to an Fanceefeest, made by zelph for 12 bucks and man o man is it awesome. to boil 2 cups of water takes 5 minutes, and 3/4 oz of heet. with some fuel left over still burning after im done boiling. It reduced my entire kitchen weight not including fuel to about 8oz-Pot, stove, lighter, windscreen - Everything about 8oz.. Mine came with a simmering ring which reduced consumption of fuel time greatly. I am very happy with my change over

[SWODaddy]

So I have been using canister stoves (jet boil, MSR, kovea, etc.) that I have been really happy with and no real desire to change. However, local conditions have forced me to explore alky stoves. I have made about a dozen (penny, can, AL beer bottle, etc.) and had thought they were all about the same...until I used a caldera cone. That stove that comes with it is about twice as efficient as my efforts thus far. In an effort to stand on the shoulders of others, what fuel sipping stoves have you come across? Thank you in advance.

I haven't found anything that beats the 12-10 stove coupled with a caldera cone. The Zelph Starlyte is very nice (I prefer it if I'm going fry something) but the 12-10 is perfect for fast efficient boil times.

[Uncle Joe]

I've only really wished I had a canister stove once. I was trying to light my alcohol stove in about 15F weather with a bit of a breeze. My campmates had already boiled water by the time I got mine going. I now own a Pocket Rocket and will carry it when it gets cold, most likely. As well as on any high elevation hikes just to be sure I have the ability to cook. I'm sure others will chime in that they've cooked just fine at elevation and in cold and I'm not doubting that. All said, I use my alcohol stove all the time. In fact, my MSR is new and I've yet to cook with it.

[HooKooDooKu]

I've only really wished I had a canister stove once. I was trying to light my alcohol stove in about 15F weather with a bit of a breeze. My campmates had already boiled water by the time I got mine going. I now own a Pocket Rocket and will carry it when it gets cold, most likely. As well as on any high elevation hikes just to be sure I have the ability to cook. I'm sure others will chime in that they've cooked just fine at elevation and in cold and I'm not doubting that. All said, I use my alcohol stove all the time. In fact, my MSR is new and I've yet to cook with it.

Canister stove for 15ºF ?
Sounds risky. I've run into issues using a SnowPeak MaxLite in temperatures in the mid 30's.
From what I understand, it's not impossible to use canister stoves at temperatures below freezing, but there are apparently various tricks you must employ to make it work.
http://bushwalkingnsw.org.au/clubsites/FAQ/FAQ_Mixtures.htm

[atraildreamer]

For the committed "stovie":


http://www.whiteblaze.net/forum/show...ncy?highlight=

[QiWiz]

So I have been using canister stoves (jet boil, MSR, kovea, etc.) that I have been really happy with and no real desire to change. However, local conditions have forced me to explore alky stoves. I have made about a dozen (penny, can, AL beer bottle, etc.) and had thought they were all about the same...until I used a caldera cone. That stove that comes with it is about twice as efficient as my efforts thus far. In an effort to stand on the shoulders of others, what fuel sipping stoves have you come across? Thank you in advance.

A Caldera Cone's efficiency is because of the excellent wind protection and concentration of the stove's heat on the pot. It's not the stove, it's the Cone. A well designed windscreen and having your pot at the optimal height above an alcohol burner will come close, but not equal it, in my experience. However, the Cone is a relatively heavier method of wind protection, so that aspect an be considered in the whole sorting out of options.

[swisscross]

Another old thread.
http://www.whiteblaze.net/forum/show...ghlight=Copper

[Odd Man Out]

It really makes little sense to ask which stoves are efficient. A stove, wind screen, pot, and pot stand all work together as a system, so you need to ask what systems are efficient (how much fuel needed to boil). Of course the other parameters people worry about are power (how many minutes needed to boil) and total system weight. For stoves that require a pot stand, if you stand is too high or too low, efficiency suffers. You need to do some testing if your goal is to optimize your system. Some stoves work better with wide pots and some work better with narrow pots, so pot choice can also be important. As you observed, the windscreen is a key component. It's job is not just to block wind. It also directs air/heat flow, controls oxygen input, and facilitates heat transfer. If you see someone using a crumpled up sheet of aluminum to block the wind, you can bet their system has not been optimized. That's not necessarily a bad thing; for some people it's not important. But if optimization is your goal, then always think about systems and how all the components work together.

In general, it will be easier to get high efficiency with low power stoves. Getting high efficiency and power together is trickier. I spent years measuring, testing, and experimenting to get a system I like (BTW, ease of use and safety are two other parameters I have considered during development). My system uses an eCHS stove with an Olicamp XTS pot and a minimal aluminum flashing windscreen/pot stand combo (not a cone). It boils two cups of room temp water with less than 15 mL (1/2 oz) methanol in less than 4 minutes. Well optimized cones can do the same with the same stove. I suspect this is reaching the limit of what is reasonable in power and efficiency with an alcohol system. The biggest drawback of my system is the Olicamp XTS is bigger and heavier than an ultralighter may like (but that's less of a concern for me). But it is bombproof and very nice to cook in and eat from (I boil food in the pot and then cook it in a pot cozy).

[mauiarcher]

A Caldera Cone's efficiency is because of the excellent wind protection and concentration of the stove's heat on the pot. It's not the stove, it's the Cone. A well designed windscreen and having your pot at the optimal height above an alcohol burner will come close, but not equal it, in my experience. However, the Cone is a relatively heavier method of wind protection, so that aspect an be considered in the whole sorting out of options.

That is what I thought, then used my other stoves with the cones. It just seemed like my stoves burned hotter but quicker (both in more fuel consumption and boil time). I got a slower boil time with the 10-12 stove but used way less fuel. It is like the right mix of heat and burn rate. I don't mind a couple extra minutes of boil time as I am setting up my tarp or whatever. When I get back, I will modify my can stoves with less burn holes to see if I can get them more efficient.

Sent from my SM-G935V using Tapatalk

[Uncle Joe]

Canister stove for 15ºF ?
Sounds risky. I've run into issues using a SnowPeak MaxLite in temperatures in the mid 30's.
From what I understand, it's not impossible to use canister stoves at temperatures below freezing, but there are apparently various tricks you must employ to make it work.
http://bushwalkingnsw.org.au/clubsites/FAQ/FAQ_Mixtures.htm

All I know is the guys with Jet boil type stoves were done before I was.

[MuddyWaters]

. As you observed, the windscreen is a key component. It's job is not just to block wind. It also directs air/heat flow, controls oxygen input, and facilitates heat transfer. If you see someone using a crumpled up sheet of aluminum to block the wind, you can bet their system has not been optimized. That's not necessarily a bad thing; for some people it's not important. But if optimization is your goal, then always think about systems and how all the components work together. <br>

Bingo

Heating a pot is a competition between making heat and transferring to pot, and losing heat to surroundings.

You can get on order of 0.4 -0.5 fl oz alcohol for 2 cups boil with a simple setup. I do it with an open cup from small tealight , it doesnt get any simpler. No stupid priming, waiting to bloom, etc. Fill, light,.

Most alcohol stoves are just .....simplicity made difficult. Making a bunch of little flames instead of one big one...for looks, not performance.

The trick is to have tight windscreen to retain heat, optimized air intake, burner to pot distance to put hottest part of flame on pot, pot bottom area that matches flame . you want the bottom of pot covered by spread flame, but not going up sides. Wide shallow pots are far supior because they have more heating area.. But most importantly....be willing to slow down. 1/2 to 3/4 of heat is being lost to environment, make heat faster than pot absorbs it, and this innefficiency goes up.

Boiling water in 4 min vs 7 isnt worth worrying about when requires carrying extra wt. Excess air reduces the flame temperature , and reduces heat transfer. Think 3/8" gap between heat shield and pot, all way around ft or a small 2 cup pot, with air holes sized just so flame isnt rich (orange and sooty viewed in dark).

If your not willing to slow down, you need help to lose less heat to ambient...heat exchanger, pot insulation, heat shield that totally encloses pot, etc.

The best feature of caldera cone is wind resistance imo. But , just be willing to slow down a bit, use handy items to make windbreak( water bottles, foodbag, etc), and you can have efficiency for a lot less weight. My pot, stove, potstand, windscreen weigh total of .....1.9 oz. When I see people carrying 7oz caldera setups, i have to wonder ...why??? My cannister setup is only 6.8 oz, including the 3.5 oz weight of empty small cannister. But to each their own.

[Deacon]

That is what I thought, then used my other stoves with the cones. It just seemed like my stoves burned hotter but quicker (both in more fuel consumption and boil time). I got a slower boil time with the 10-12 stove but used way less fuel. It is like the right mix of heat and burn rate. I don't mind a couple extra minutes of boil time as I am setting up my tarp or whatever. When I get back, I will modify my can stoves with less burn holes to see if I can get them more efficient.

Sent from my SM-G935V using Tapatalk

How much less fuel? With my Fosters can Caldera setup, I've found I need 20ml
(.75oz.) alcohol to boil 2 cups of 70 degree ambient water with the 10-12 stove. I'd be curious to know what you've found.

I still go back to using Esbit, as I can boil the same amount of water with a 0.5oz cube, have the ability to blow it out, and have about 30% of the cube left. This using the gram cracker stove that weighs all of 4 grams.

[Odd Man Out]

...But most importantly....be willing to slow down. 1/2 to 3/4 of heat is being lost to environment, make heat faster than pot absorbs it, and this innefficiency goes up....

Yes, the conflict between efficiency and power is true in most energy transfer systems. Sprinters run fast (more power), but only for short distances (inefficient). Marathoners are the opposite. If I race against a Dodge Viper (power) in my Toyota Prius (efficient), I loose for sure in the 1/4 mile, but give us both a gallon of gas for a 40 mile race, I win.

[Secondmouse]

Bingo

Heating a pot is a competition between making heat and transferring to pot, and losing heat to surroundings.

You can get on order of 0.4 -0.5 fl oz alcohol for 2 cups boil with a simple setup. I do it with an open cup from small tealight , it doesnt get any simpler. No stupid priming, waiting to bloom, etc. Fill, light,.

Most alcohol stoves are just .....simplicity made difficult. Making a bunch of little flames instead of one big one...for looks, not performance.

The trick is to have tight windscreen to retain heat, optimized air intake, burner to pot distance to put hottest part of flame on pot, pot bottom area that matches flame . you want the bottom of pot covered by spread flame, but not going up sides. Wide shallow pots are far supior because they have more heating area.. But most importantly....be willing to slow down. 1/2 to 3/4 of heat is being lost to environment, make heat faster than pot absorbs it, and this innefficiency goes up.

Boiling water in 4 min vs 7 isnt worth worrying about when requires carrying extra wt. Excess air reduces the flame temperature , and reduces heat transfer. Think 3/8" gap between heat shield and pot, all way around ft or a small 2 cup pot, with air holes sized just so flame isnt rich (orange and sooty viewed in dark).

If your not willing to slow down, you need help to lose less heat to ambient...heat exchanger, pot insulation, heat shield that totally encloses pot, etc.

The best feature of caldera cone is wind resistance imo. But , just be willing to slow down a bit, use handy items to make windbreak( water bottles, foodbag, etc), and you can have efficiency for a lot less weight. My pot, stove, potstand, windscreen weigh total of .....1.9 oz. When I see people carrying 7oz caldera setups, i have to wonder ...why??? My cannister setup is only 6.8 oz, including the 3.5 oz weight of empty small cannister. But to each their own.

I agree boil time is irrelevant on the trail and my entire focus is on efficiency.

I'm very interested in your statement "Most alcohol stoves are... just simplicity made difficult"... I've been playing with different alcohol burners to find my favorite but if what you say - open burning in the tin from a tealight candle is as efficient as anything else - then you've opened my eyes to a whole new world in alcohol.

discussing windscreens being tight around the pot, do you also think it is necessary that they go very much up above the pot/flame juncture?..

[Odd Man Out]

I agree boil time is irrelevant on the trail and my entire focus is on efficiency.

I'm very interested in your statement "Most alcohol stoves are... just simplicity made difficult"... I've been playing with different alcohol burners to find my favorite but if what you say - open burning in the tin from a tealight candle is as efficient as anything else - then you've opened my eyes to a whole new world in alcohol.

discussing windscreens being tight around the pot, do you also think it is necessary that they go very much up above the pot/flame juncture?..

I also agree. I expect that most alcohol stoves have the same "efficiency" measured in heat produced per gram of fuel burned. What we define as efficiency is how much of that heat gets delivered to the water. What fancy stove designs may accomplish over a simple tea light burner is generate more power. But without the system to capture the heat, it is lost. And if power is not a concern of yours, more powerful stoves are also not important. This is why there is no system that is "best". Each person has their own parameter priorities. If you are looking for a simple but low power burner that has many advantages and commercially available, I recommend the Zelph StarLyte. I used this with good success before switching to the more powerful eCHS stove. I like the one without the integrated pot stand and the cap. This way you can store excess fuel in the stove for next use. This increases effective efficiency with is something many people ignore to consider.

If you have to burn off excess fuel after each use, you are actually burning much more fuel than necessary, greatly decreasing the effective efficiency as it is used in the field. An important way to increase effective efficiency as you actually use the stove is to have one that can be extinguished when done and excess fuel either stored or recovered. I don't like it when my ability to guess accurately the amount of fuel needed is a key determining factor in the efficiency of fuel consumption.

[SWODaddy]

Wide shallow pots are far supior because they have more heating area.

IME, I don't think this is true for a Caldera setup, which envelops the sides of the pot, coupled with the 12-10 stove that has a very narrow flame. My wife has an Evernew 640ml "tall" pot caldera setup. I have a Evernew 900ml squat caldera setup. We never timed it, but she can boil 2 cups of water considerably faster than me.

[Secondmouse]

IME, I don't think this is true for a Caldera setup, which envelops the sides of the pot, coupled with the 12-10 stove that has a very narrow flame. My wife has an Evernew 640ml "tall" pot caldera setup. I have a Evernew 900ml squat caldera setup. We never timed it, but she can boil 2 cups of water considerably faster than me.

the Cone is obviously a great optimizer due to its blocking wind and containing the heat against the entire surface of the pot.

I don't know enough about it to speculate beyond that but it still doesn't make sense that heat contained against the sides of a tall pot is more efficient than heat applied directly to the bottom of a shorter/wider pot. maybe height above the flame has something to do with it?..

[gbolt]

Bingo

Heating a pot is a competition between making heat and transferring to pot, and losing heat to surroundings.
Most alcohol stoves are just .....simplicity made difficult. Making a bunch of little flames instead of one big one...for looks, not performance. The trick is to have tight windscreen to retain heat, optimized air intake, burner to pot distance to put hottest part of flame on pot, pot bottom area that matches flame. If your not willing to slow down, The best feature of caldera cone is wind resistance imo......1.9 oz. When I see people carrying 7oz caldera setups, i have to wonder ...why??? My cannister setup is only 6.8 oz, including the 3.5 oz weight of empty small cannister. But to each their own.

Your Killin Me Muddy Waters! Lol. However, I can't disagree with you. However, I did take the liberty of cutting out sentences from your quote to create a paragraph to help me sell my Caldera Cone Cooking System in the For Sale Section.

One update I can provide is the state 7 oz Caldera Set Up weight. That is based on whether you carry the Plastic Container/ Canister that doubles as a cup and holds the cook system. My alcohol stove and caldera cone w/o the container is 99g 3.45 oz. The container is 3.3 oz and so together they are 6.75 oz 192g. (Close enough to your 7oz)

I hate slowing down and much prefer the ease of the Canister Stove over the Alcohol. Had I not switched from the old MSR Whisperlite to the newer Micro Rocket before playing with the Caldera System, I might not feel the need to sell the Alcohol Stove. Like you I will trade weight for the canister setup for my confidence and preference.

[SWODaddy]

the Cone is obviously a great optimizer due to its blocking wind and containing the heat against the entire surface of the pot.

I don't know enough about it to speculate beyond that but it still doesn't make sense that heat contained against the sides of a tall pot is more efficient than heat applied directly to the bottom of a shorter/wider pot. maybe height above the flame has something to do with it?..

I think (speculate) it's a couple things:

1. Less volume inside the caldera cone...ie, less air and metal to heat up.
2. The taller pots sit deeper in the caldera cone. So the cone is able to heat up the sides of the pot (which are in contact with the water since it's a narrow pot).