Most efficient alcohol stove system currently?

Basically. There are lots of stove designs n setups which give 15ml/2 cup boils at home.  You won’t get much better due to the fuel energy capacity.    Especially in the field (wind etc).  I assume 20ml when packing for a trip which gives leeway.

I’ve played with many stove n pot/windshield combos over the years and sadly also measured time/efficiencies. ;)

I’ve got 15ml efficiency for a 2 cup boil with various setups

Field results are more variable due to wind and uneven ground (flame gap can vary if stove not the potstand too).

I have always got best results with :

A Caldera Cone or more often, home made Cone. It’s a no brainer to me. Maximum heat is retained in a well designed setup ( airflow obviously needs tweaking for optimum system performance),  and it’s got inherent stability.

In terms of speed + efficiency a short wide pot.E.g. AGG 3 cup, Trangia, or Evernew 600 or 900. Has performed best.  MSR Titan Kettle also ok. Taller narrower mug types a little less effective IME.  ( marginal though).

Stove has mattered less, I’ve had 15ml boils many times with a standard Starlyte . ( modified not necessary for wide pots in my experience – just slower)

<span style=”line-height: 1.8;”>My first efficient UL stove was the Zenstove mini chimney (red bull/V8 can) – good performance with the AGG pot and a cone(homemade).  I switched to Starlyte in 2010 as it has several advantages.  </span>

Best/consistent setup is the Evernew 600 with a Caldera Sidewinder and Starlyte.

Mostly use an Evernew 900/cone/Starlyte at present if with my partner or cold weather.  We just used it for a 2 week trip in the Pyrenees.  Perfect size for boil only use.

Basically. There are lots of stove designs n setups which give 15ml/2 cup boils at home.

I have a Trail Designs 12-10 stove, paired with one of their Caldera Cones and a Toaks 850ml pot. I have been using it this pass week whilst riding the Holland Track in Western Australia. Some days I was boiling water in “destructive winds”.  The water water was at ambient temperature been collected from rock pools.  My “real world” experience was 13 to 15ml to boil around 250-300ml and 30 ml to boil around 500 to 600 ml.

Interested in the Toaks stove if it could be used with my Caldera Cone.

I agree with Mole. Most alky stoves are about the same with only a couple grams of difference. Mostly, it is a matter of fuel heat density. Methanol is not the best fuel but works well. Ethanol is about the easiest to get with a fairly high density heat content. Denatured alcohol (methanol/ethanol blends) also are fairly easy to get and work pretty well. The overall heat content can vary about 1/3 between pure methanol and pure ethanol. Unfortunately, fuel type is often not given.

For short two to five day trips, light alcohols remain the most weight efficient fuel. It burns easily. But, due to the OH (you can think of it as partially combusted) it lacks heat density. On longer trips, it is overtaken by the higher fuel heat densities of the butane/isobutane/propane blends, even longer trips/larger groups by white gas/kerosene because they don’t require a pressure vessel except while heating. Few take three week, unsupported trips, though. IFF you are extremely careful, snuffing and recovering unburned fuel in a high efficiency burner, alcohol can match canister gas, but it is a lot of fussing. Some of the SUL people get really good efficiency out of really simple alky stoves. Canisters are the easiest to use, but unless you have a remote stove, it is difficult to use a high efficiency wind screen.

My guess would be a Caldera Cone system. I always measure 15ml but only usually boil 12oz water at a time (occasionally 15) and I have no problem even in the wind. I use the evernew 500ml pot.

I have found non cone alcohol stoves as well as regular canister stoves very inefficient in the wind and even jet boils seem to fall short. The msr reactor seemed to handle wind really well.

On a side note I have been unable to find a situation where canister stoves are lighter even on two week trips. I have made spreadsheets using .14oz of fuel used per jet boil “boil” and .45oz per Caldera Cone boil and the heavier stove and fuel canisters always seem to make the jet boil have a higher average weight.

The best fuel efficiency is derived by a number of factors, the stove is not the primary factor

1. Set up – placing your cooking system out of the wind is the primary factor.  Finding a location that is out of the direct wind AND keeping your system on the ground is the best way to reduce the effects of wind.  On a windy day, I have measured the wind velocity from chest height down to the ground and the difference can be 5X to 10X.  Wind causes your alcohol stove to burn faster, shift the flame front off center of your pot/mug and cool the pot/mug down.  This is the case with all stove, alcohol and Esbit burn slower and are more sensitive than canister stoves.
2. Fuel measurement – as stated earlier, a good alcohol stove will boil 2 cups of 70 F water using 15 ml of DA.  Most people add too much alcohol and basically waste a lot of fuel.  Additionally compensating for the water temperature incorrectly.  In general, you need to add 1 ml for fuel for each 10 F below 70 F.  For water at 32 F, you need to add about 4 ml more for a total of 19 ml.  Yeah in know, in the field add a little more, but not that much more.
3. Add a heat reflector – a lot of energy is loss through the ground, adding a foil heat reflector (over snow or wet ground), will reduce your time to boil and help with your fuel efficiency.

Bottom line, an alcohol stove is only as good as your setup and how the system performs together.  My 2 cents.

The most fuel efficient stove that I know of is St. Rock’s Ion stove.  With the right set-up, he was able to boil 2 cups using 12 ml of alcohol in about 8 minutes.   With his design, I got to 13 ml to boil 2 cups, however; I never got the time to boil numbers.

“the more you burn, the more you learn”

Has anyone had a custom Caldera Cone made for the Toaks Siphon Alcohol Stove?   If so, how did it work out for you?

https://www.traildesigns.com/stoves/caldera-stoves

http://toaksoutdoor.com/toakstitaniumalcoholstove.aspx

SGT Rock has a good write-up and building instructions for the Ion Stove on his website (but the order-a-premade-stove links are broken):
http://hikinghq.net/ionstove/

Trail  Designs will make custom screens for different pots not stoves, you can use the 12 10 stove or the starlyte stove for alcohol use with there Cones, they do not recommend other stoves with their Cones, that is not to say people have not tried other stoves .

I just found a somewhat recent Reddit thread discussing this same subject:

Best alcohol stove? (Efficiency and versatility) from Ultralight

there are also many threads on the subject on BPL including this one from a couple weeks ago

HELP WITH COOK KIT .

As Jon pointed out, it’s hard to precisely measure the alcohol you’ll need for current conditions – wind, temperature, water volume, etc. So you add a little more than you need. Most alcohol stoves must burn off all the fuel you’ve added.

Stoves like the Starlyte can be more efficient. Fill it up with alcohol and light. When your water boils, blow out the flame, wait a bit for the stove to cool, and put the lid on. The remaining alcohol stays in the stove.

And you’ve use exactly enough alcohol for that meal under those conditions.

— Rex

Resurrecting an old thread I know, and maybe this toping has been done to death already but I’m finding Tetkoba’s eCHS stove with a few tweaks can boil 2 cups of water outside with 12ml of ethanol. I know thats not the same as methanol/heet but perhaps that gets closer to the answer to this question. I documented an outdoor boil test at cool temperatures here…I can get better performance inside/warmer temps but I don’t feel that is a fair test. I’m keen to hear thoughts of those more knowledgeable than me on the topic.

First of all, good job.  I did review your video and I think that there are some minor corrections that need to be made regarding the calculations.

0.95*21.49+.05*24.88=21.99   The number has to be higher than the LHV Ethanol as you are adding a higher value of Iso to it.

Please explain where the 96% comes from.

All good, just needs a little tweaking and refinement.  My 2 cents.

Hi Jon thank you very much for your reply and review of my numbers. I really appreciate it.

I made a mistake carrying over the text from excel to the video. It was meant to be ethanol LHV of 21.148 kJ/ml * 0.95

so it should carry to my same result of 21.33 . Thanks  good catch!

The 96% of the fuel used to boil…i just took the time used for the boil divided by the total burn time. I was doing that when e.g. I had much more fuel left over but maybe in this case where the fuel ran out right after it is just splitting hairs though.

5:06/5:19 = 306sec/319sec = 96%

I shall make some updates to the caption tonight. Thanks for that.

So, the most fuel efficient alcohol stove system that I know about is Sgt, Rock’s Ion Stove.  It was able to boil 2 cups of water using 10-12 ml of alcohol.

http://hikinghq.net/ionstove/build.htm

It is system dependent, I got it down to 13 ml but no lower.  People have verified that it works in some system.

FYI, I would recommend that run the test 6 times and look at the average and standard deviation numbers as a sample size of 1 can be a roll of the dice.  I am not saying that you are wrong, just that the statistcal strength of a sample size of 1 is relatively low.  My 2 cents.

Pardon my ignorance on the subject, as many here know way more than myself since I don’t cook on the trail unless I need to melt snow.

But, wouldn’t one eventually just go to Esbit if they are looking for the best weight ratio for cooking? Alcohol is more versatile in which fuels you can use and where to get them, but if Esbit is easy to access, isn’t it preferred in terms of weight? I don’t cook, but I can melt 32 ounces of water out of 25*F snow with 1 once of Esbit with a setup that isn’t even close to maximum efficiency. Is that a good ratio?

@ Johan – good question.  Esbit (and other Solid Fuels) can be more efficient than alcohol on an energy per unit weight basis.  Solid fuels have several issues that sometimes can be dealt with.

Quantized fuel volume.  Esbit I believe comes in 4, 7 and 14 g blocks.  I think that there are some that are mega sized, but I’ll ignore those.  I can easily boil 3 cups of water with a single Esbit tablet, but I usually only heat up 2 cups.  Some people blow out and re-use Esbit, others don’t like to do that.  If you don’t recycle, efficiency will drop.

Burning alcohol smells, to me Esbit smells far worse.  It depends upon your tolerance.  Outside backpacking, I find it tolerable, but not desirable.

I have actually come to the conclusion that when you add in ambient wind, an Isobutane stove with an HX pot can be more efficient than either system.  My 2 cents.

Esbit (and other solid fuel) will leave a residual soot on your cookware.  Big deal for some, not for others.

Thanks for the reply Jon. Makes sense. I can see how the Esbit smell isn’t ideal when cooking. I only melt snow, so I can just walk away for a minute while it melts, and don’t have to worry about losing my appetite. I also eat sardines on a daily basis at home, so bad smells don’t really hit me as hard as other people. LOL Still though, I think Esbit is way better smelling than camp fire wood smoke, that’s for sure.

My experience with alcohol stoves is dated… I switch to primarily esbits in 2009 (canister when fire regulations require it). Back then  there was a fair range of stove efficiency.  The Vargo Triad Alcohol Stove was one of the least efficient stoves I tried. Sgt Rock’s Ion was the most efficient. In the field I would use 12-15grams to boil 20oz of water… but it was S*L*O*W … around 14 minutes.

Thanks all of you for your replies. Jon thanks for the recommendation to look into the ion. I noticed your Cat-Ion stove after you mentioned the ion and will try my hand at making one. It might be more of a warm-weather stove option though with a lower output

I did as Jon suggested and repeated my tests, setup exactly as shown in the youtube video above. My results are below for 6x runs, in both metric and US units. Runs were spaced between 2 days and 1 hour apart (to ensure everything cooled). I used the same calculations as previous. Stove was left alone outside for 1 hour before filling for any testing. Where the stove boiled the water in the pot before it ran out of fuel I continued to time and assumed that the % of time spent getting the water to boil equated to the % of fuel used to boil, for the “thermal efficiency” column.

I like what I’ve found – I think what I’ve ended up with is a very efficient (by the accounts of other very efficient stove fuel usages), relatively fast/high power for an alcohol stove system (5 mins to boil 2 cups of water on under 12ml fuel), and fairly fuss-free setup that works at the described performance near freezing temps. I will test it further sub-freezing later this winter.

I’m very happy to hear any more comments/thoughts/advice/critique.

The results look very good (FYI- the picture is hard to read unless you download it).  What is this biofuel that you are using: is it commercially available or your own mixture?  I ask because the results look good, however the fuel looks uncommon.  We rarely see denatured alcohol with isopropyl in it.  To replicate your results, I would have to hand mix the fuel mixture as it is not available in the US (that I know of).  I myself would be interested to see a few test runs using just ethanol (and a little water).  This would be a baseline that would easier to compare.  Keep up the excellent work.

Thanks Jon,

The fuel is relatively new, sold in Canada as e-NRG bioethanol and a quick google suggests they are based in California. It is marketed as safe to burn (in an “ethanol fireplace”) indoors and it seems since I discovered it, lots of hotel chains have added their name to the webpage as named clients…I found its lack of any other (more) toxic stuff attractive as a fuel. I imagine you could buy it in the USA. I think its a really good option and maybe a newer less toxic fuel to use in the future, but probably less easy to find in trail towns so far.

The SDS lists 80-100% ethanol and 1-20% isopropyl alcohol but I called around and got the response “about 5%” for the isopropyl portion. A quick play, if I max out the isopropyl ratio to 20% my efficiency calc drops from 68.1% to 66.4%

I sometimes have access to some lab grade ethanol. I’ll see if I can get a few tests done with that in the next few weeks to give you a more meaningful comparison.

lots of hotel chains have added their name to the webpage as named clients…
I wonder whether the hotel chains know their names are on the web site?
Did they buy, or were they sent free samples?

Cheers

I understand the need to calibrate your fuel use, so that you bring the right amount on a trip. But I’m having a hard time understanding why it’s important to optimize use to the mL. Even if one used an extra 10mL per day, wouldn’t that be only 2 ounces of extra weight for a week-long trip? Or is this more of a theoretical discussion?