Are you taking into account the number and weight of the containers required for butane and other fuels? Plus the inconvenience of packing an odd-dimensioned containeer that you cannot decant from?

It's OK to carry on about fuel efficiency, but there are other trade-offs. What the fuel is carried in counts as much as anything else.

This is a nebulous statement. Just what does "well within what I would expect for comparison to hydrocarbon fuels"?

You likely would have discovered this information if you had researched sufficiently.

Say wha...?

You can't burn a lower heat content fuel at twice the rate and transfer heat faster by just making the pool of fuel larger. First, the fuel has a specific amount of heat per mass. If it has less heat per mass, you have to burn more of it to transfer that heat. If you make a large pool of it, you just lose more of the heat to the surroundings. You also have mass transport problems with larger pools of fuel. The yellow flame of your picture and the sooted bottom of the pot indicate that you aren't burning the fuel efficiently because the fuel isn't getting enough oxygen.

There are natural laws that you simply can't violate which dictate how much heat a substance has and how fast that heat can be delivered. You can't break them or even bend them. You may think you have bent them but you really haven't. You are likely comparing caulk to cheese by doing a poorly controlled experiment. You can compare the fuels and the heating rates but you need to use equipment that is the same or at least similar enough to give you a meaningful comparison.

Let's not wander off into silly territory. Sticking to the point of liquid fuels used for camp stoves, there is definitely a difference in the energy transfer between ethanol and kerosene and the equipment used to burn the fuel. For example, kerosene used in a Trangia would provide more heat than ethanol because it has a higher amount of energy to give up. In an open burn situation, however, the amount of oxygen getting to the fuel would be limited and it would burn cool. It would produce lots of unburned carbon which is an indication energy loss. Pressurize it, atomize the fuel and efficiently mix it with oxygen and you can capture nearly all of the energy the fuel has to offer.

On the other hand, if you were to do the same with ethanol, i.e. pressurize it, atomize it and efficiently mix it with oxygen, you would see a gain in capturing energy but there isn't as much to gain as hydrocarbon fuels. Your fuel is partially oxidized and therefore doesn't has as much energy to give up.

I hate to break this to you, but most of the alcohol fuels you are likely to use, outside of something like Everclear, are produced from petroleum. Drinking ethanol is made by biological processes and has been for millennia. But commercially produced ethanol that is use in denatured ethanol is made through refining and cracking and treating oil.

Yes the -OH is on the middle carbon atom, my high school chemistry is a bit rusty, the way I learned it was to put the number of the carbon atom next to the functional group hence propan-2-ol and propan-1-ol

When I got away from alcohol stoves, it felt good to be no longer so cramped and limited by their incapabilities. Glad I'm out.

To convey something of what it felt like making the transition, this comes to mind as a reasonably good approximation:

The only short coming of alcohol over butane/isopronanol is the lesser energy density and as far as the stoves go its the inability of most alcohol stoves to adjust the heat output.
Alcohol stoves are simpler and lighter for trips where you're away from resupply for up to a week, longer and I'd start to consider a canister. Also whatever the energy density the efficiency of your cooking system is going to depend on other factors that contribute to the transfer of energy from the fuel to your food or water. The base weight and volume overhead of a canister stove is larger than that of an alcohol stove, but for multiple people and weeks away from resupply that vcan be overcome.

I've heard that some people like Windows and some people like Macintosh computers. Luckily, those folks never argue about that. :rolleyes:

Sorry, I've been away for a bit, out chasing some mountain lions down.

This would require a bit of explanation. I may start a thread in case there might be others who would be interested but are not following this thread.

But I want to get to some other things right now, and might not get to it right away.

The idea allows me to do my favorite types of touring (forest service roads, trails, high desert, middle of nowhere, middle of everywhere sorts of trips that take me away from stores and other places where one might find the usual sorts of fuels being sold) without having to interrupt those fine sequences of days and weeks in the wilderness, with the mountain lions and the prairie falcons.

And the moon and the sun, and the hot springs, and the sky and clouds, and trees and rivers and hummingbirds and eagles and wild horses.

Niles, have you been munching on those mushrooms again?

As a matter of incredible coincidental serendipitous fact, yes -- just found a very unusual bonanza of honey mushrooms and the delectable lion's mane, which is a real delicacy.

If I use a pot stand so the upper ring of jest on the Evernew stove ignite I get boil times of 4 mins for 2 cups of water. However this uses 0.75 oz of ethanol, so I just sit my mug on top of the stove, blocking off the upper ring of jets and giving me a 5 to 7 min boil for 0.5 oz of ethanol. This shows that stove configuration is as important in energy density when figuring out efficiency.

Well that certainly clarified things

Soda can percolator! Teach me, please. I made the Jurey penny 2 stove recently. Works pretty well. I boiled 2 cups of water at a high boil. I was wondering about coffee, though a filter seems easier.

I'm using ever clear. I like that is not poisonous.

You are assuming that the stoves project their heat from only the burning pool. They don't, as was explained to you earlier.

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In Australia (we don't just talk about the US in these forums), bioethanol is produced from organic products including sorghum and sugar cane. Petroleum is not used as the base. It never has been, as far as I am aware -- the plant would be readily identifiable as there are only a handful of petroleum refineries in the country, and Caltex seems likely to close one soon.

Certainly the chemical plant in Alberta that Machka worked for that dealt with ethylene used its gas and oil supplies to produce plastics. Nope, no ethanol there, either.

I also did a google search that stated that only 5% of the world's production of ethanol came from the petroleum source in 2003.

Then, Wikipedia (the go-to for all discussions like this, eh?) stated that the TCX Technology was invented by Celanese and was launched in only 2010. Celanese expects to produce from three new plants (two in China, one in Texas) 300 million gallons of TCX ethanol by 2016. There was no mention of volume petroleum production in Brazil or Argentina, which have high ethanol usage, but there was some mention of exports from the Middle East of some petroleum-based ethanol.

The other methods of obtaining ethanol from petrochemical feedstocks are virtually obsolete, with Lyondell-Basell Industries being the only company to still use one of them. The article said that petroleum ethanol was used only as an industrial feedstock.

Methylated spirits also is not taxed in the same way as gasoline, and therefore the production and make-up of methylated spirits is tightly controlled by various governments.

So where does the rest of the petroleum-based ethanol that you allude to come from?

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The shortcomings of alcohol stoves have been mentioned time and again, not only in this thread, but in previous ones where you have slapped down posters with all sorts of theory... and that's just what it has been, because you admitted in this thread that you haven't done enough practical research to provide a realistic and balanced critique of the equipment and fuel source.

But ultimately, the same defence you use for the integrity of your chosen stove applies here -- it's up to the user to beware the issues and to act appropriately.

By the way, I was in an outdoor supplier at the Grand Canyon today and looked at the Whisperlite stove (complex and I can understand how it can go wrong), the Jetboil (a bulky package if the jug is included, and you still have to buy the plastic base to create any sort of stability, plus tote around the cannisters), the PocketRocket (which I am already familiar with because I own one), and the fuel cannister to power the Jetboil and PR (and those weigh a fair bit). Then I looked at the can of denatured alcohol and thought, yep, even here you can get something to power your Trangia.

Denatured alcohol is denatured with all kinds of things. I do french polish, and you have to be careful as to the brand, some are really nasty for skin contact. If you search out FP threads you will get all kinds of stuff. I wish we could get everclear cheap.

Denatured alcohol is sold as such up here, but far more common is that it is in a bottle named fuel line anti-freeze. Even in summer. At one point they seemed to vary the labels by season, but now it often is sold as anti-freeze all year round.

Yes actually I am taking that into account. I have not done the calculation lately because alcohol is the slam dunk winner for both weight and availability on pretty much any bike tour I have done.

Alcohol is also likely to be the weight winner for short backpacking trips, but by a lesser margin. I forget the exact length of time between restock where butane started to have a weight advantage when I last did the calculation, but I think it was at about a week between restocking. Of course that will vary with the particular stoves and fuel containers.

If I go more off of the beaten path for a week or more I'll take butane or white gas, but I usually only do that on wilderness canoe trips.

I do have a planned backpacking trip where I am still undecided on fuel. It is 3-4 weeks long and I am trying to figure out fairly frequent mail drops so I can go light. If the mail drops work out frequently enough I'll go with alcohol.

I'm looking for an alchol stove for camp mug water boiling, the 2 cup size. seen lots of designs, built and used many of them, but still after the perfect combo. For me, that would be a stove that has a center flame (as opposed to side jets) that does not need a pot stand and is stable on uneven ground. I user a super cat stove for my wide bottom tea kettle, which works great, but for a small diameter cup, the flame pattern is lost around the sides. This would be for backpacking where volume in the pack is at a premium. Anyone?

I took an engineer's tour of the Coors brewery in Golden, CO. The plant engineer leading the tour showed us a couple of rail tanker cars full of ethanol, a byproduct of the beer process. He told us they add "a few gallons" of gasoline to each car to "denature" (poison) it before shipping. It's much cheaper that way, he said, because of taxes on drinking alcohol.

All this circular discussion does for me is make me pleased I found a way to free myself from cooking on bike tours and backpacking trips. But I'm sure glad I learned how to make and use alcohol stoves before I quit cooking. They're a thing of beauty in design and utility. And I still have my old Whisperlite (neither of which is true).

The Evernew TI stove with the 2 cup Evernew TI mug. It needs to be on flat ground and is a side burner, but the jet pattern is well matched to the base of the mug. The boil is gentle so the mug handles stay cool. I actually seldom bother bring water to a rolling boil as I end up waiting for my tea or soup to cool down. If I am cooking something like couscous I'll bring the water to around 180 F (lots of bubbles and a bit of a shimmer in the water), add my couscous and set it aside for 10 mins and use a T-shirt as a cozy. Experience has shown me that 0.25oz of ethanol is sufficent to get 2cups of water nicely hot (not boiling), 0.5oz will boil water in between 5 to 7 mins

http://bikeforums.net/attachment.php...hmentid=286797

:)
In the field, I've used coffee filters, instant coffee and tea bags filled with coffee. I initially built this as kind of a lark and to see if I could do it. Well, it worked so well, I've taken on a few trips.
I built it very much like a soda can stove. It takes three can bottoms; two fit together to hold the coffee and one as the stand at the bottom. The middle shaft or percolation pipe is a piece of an aluminum wind chime.
In constructing it, these are the points I tried to keep in mind:
1) The bottom end of the pipe has to stay off the bottom of the pot (so water can percolate up through it).
2) The the holes in the very top portion of the coffee holder are smaller than the ones in the bottom of it so that all water that percolates in can flow through. Preventing it from backing up. I made these holes with tiny tack nails and a hammer.

If any of the holes for the pipe to go through the middle are too big, cut a small strip of aluminum and wrap it around the pipe. It should snug right up. It needs to be pretty tight since the aluminum will expand when heated and you don't want the top portion sliding down onto the base.

It holds about two tablespoons of ground coffee and letting it percolate for about 4 minutes makes 16oz of fairly strong coffee. Just experiment a few times and you'll find your sweet spot.

Way off topic, but this confuses me. Why would they have so much ethanol from making beer? Shouldn't it be IN the beer, and how do they extract it? WTH? ASFAIK the main by product of the beer process is CO2.

Ethanol can be removed from beer by filtration (e.g. reverse osmosis) to make non-alcoholic beer, for those who drive cars instead of bikes ;)

Blasphemous



From what I can tell they are using the waste, or spent grains and trub, to then create ethanol.....interesting

Anyway, back to the great stove debate of 2012, looking forward to next year ;)

I didn't read the whole thread, so apologies for repeating anything that has been said already. Here's my take:

I have a Trangia 27 set with the alcohol burner that came with it. Simmer ring and all. It has served me well. At first I used normal PET soda bottles (with the soda texts taped over) for fuel but bought the dedicated fuel bottle for one non-solo trip, to reduce the risk of an unsuspecting touring companion taking a sip out of my fuel bottle. The dedicated Trangia fuel bottle is marginally easier to operate, but no big difference there.

The simmer ring is cumbersome but it works. Having three hands would help. This is one of the reasons I sprung for the Trangia "butane" burner, so now I have both. The butane burner is faster and easier to control - and noisy beyond belief, at least when compared to the completely silent alcohol burner. It also doesn't work well, sometimes not at all, in winter, unless you carry the fuel canister close to body. I've seen people heat up their fuel canisters with candle flame. A bit too hardcore for me.

The alcohol burner tends to get more use, mainly because I really prefer peace and quiet when I'm in the forest. I'd be OK using the butane burner in a camping area, or roadside stop, but in the woods it seems just so wrong. :)

--J