Simple, Featherweight Alcohol Stoves for Camping
I take occasional backpacking camping trips in the mountains of the northeast U.S. I have a large backpack, and used to simply stuff into it or lash onto it whatever camping gear I had on hand: heavy tent, heavy sleeping bag, heavy air mattress and pump, and relatively heavy stove. My load could exceed 50 pounds (23 kg), including food (hot dogs & fixings) and water for the family.
Today I could still stagger along under this weight, but it would no longer be fun. Therefore, I am lightening up my camping gear. Unfortunately, lighter usually means more expensive. A down-filled sleeping bag was lighter but more costly than a similar bag using synthetic polyester fill. For 2-person tents, I looked longingly at the nice, taut, lightweight (4.5 lb = 2 kg ) MSR Hubba-Hubba but could not swallow the $ 330 price tag. I settled for the Kelty Gunnison 2.1, which has two large vestibules, sells for $160 through www.campmor.com and weighs 5.5 lb = 2.5 kg.
In my younger days I was happy to sleep on a cheap, lightweight closed-cell foam pad like a RidgeRest. I later graduated to a self-inflating ThermaRest. This has an open cell foam pad inside an air mattress that is about ~ 1 inch (2.5 cm) thick. It is sturdy and insulates well, but starts to get heavy and expensive if you want a full-length ThermaRest that is thicker. Even with the thickest (1.5”) versions, I find that irregularities in the ground bother me, especially when I lie on my side. To keep comfortable, I want an air mattress which is at least 2.5” (7.2 cm) thick. These are available for backpacking, but again less weight means more cash. The NeoAir (Regular size) weighs only 1.2 lb and offers superior insulation from the cold ground, but costs $120. I settled for the Kelty Recluse ($ 70 at Campmor) at 2.0 lb.
2016 gear update: Due to aging body, I had to shed yet more weight from our packs. Also, my wife wanted a slightly larger tent for us in order to not feel claustrophobic. I went with the MSR Freelight 3 at 3.5 lb. This is a nice-looking sort-of freestanding comfortable 2-person or squashed 3-person tent, with lots of mesh. Not meant for gale-swept mountainsides. List price is horrific, though I was able to catch it on sale on Campmor for a bit less. The Six Moons Lunar Duo gives about the same amount of room (and more headroom) for less weight and less money, but we weren’t quite ready to make the leap to a single-wall shelter with a slippery silnylon floor.
Also, I replaced our old exterior frame backpacks (about 5 lb = 2.3 kg each) with Osprey Exos interior frame packs (~$180 each), weighing 2.2-2.5 lb. The Exos packs have a full rigid frame and taut cool mesh patch against your back, so you can just throw gear into them any old way and the weight gets transferred nicely to the cushy hip belt. Some other packs in this weight range are floppy, so you have to load them carefully and cinch them tight to get rigidity, and they have sweaty foam pads against your back.
One area where the price/weight relationship can go the other way is for stoves. Here are two common petroleum-based backpacking stoves:
On the right is a MSR Whisperlite Internationale. Today a comparable model, the Whisperlite Shaker Stove, with fuel tank, sells for about $100 and weighs about 1.2 lb (0.55 kg). This stove uses “white gasoline”, known in the U.S. as Coleman fuel. It has a fuel tank, a pump to pressurize it with air, a valve to control the fuel flow, and a hose that connects to a burner/pot-stand. The fuel passes through a metal tube next to the burner flame to get vaporized; the vaporized fuel then shoots through a narrow jet, mixes with air, and emerges in the burner proper to combust in a strong blue flame. This is what they take to melt snow for drinking water when assaulting Mt. Everest. It is very powerful and fairly reliable, even in cold weather. It does take a minute of nasty, sooty flaming at first, to preheat (“prime”), and with all those components, it can break or clog, so the wise hiker brings along a repair kit. The MSR Dragonfly model is heavier and more expensive, but burns almost any petroleum-based liquid (white gas, auto gasoline, diesel fuel, etc.).
The stove on the left is a “canister” stove. A simple burner/pot-stand screws to the top of a butane canister. Operation is simple: open the valve and light the burner. These are fairly light and cheap, but managing the canisters can be a hassle: a trekker might have to cart along several extra metal canisters to guard against not being able to purchase them in remote locations. It is not obvious how much fuel is left in a canister, they are not generally re-filled, and (unmodified) their performance falls off in cold weather.
Alcohol Stoves Are Both Cheap And Light
In reading about backpacking cooking gear, I discovered the world of lightweight stoves that burn alcohol instead of gasoline or butane. They are both lighter and cheaper than stoves burning white gas or butane. These alcohol stoves are so simple that you can make one yourself out of a beer can or cat food can – – that means both light and cheap. Or you can buy one pre-made for around 15 to 35 dollars. They typically weigh only 1-2 oz.
One survey showed that over 50% of Appalachian Trail though-hikers end up using a soda-can type alcohol stove. According to Roland Mueser (Long-Distance Hiking: Lessons from the Appalachian Trail), alcohol was the only stove type with a zero percent failure rate. These are super-light, have no moving parts, and use fuels that can be purchased in any American small town. The recommended fuels are methanol, ethanol, or mixtures of the two. A common way to buy methanol is as the yellow bottle of “HEET” deicer, sold in automotive parts stores. Another common form of alcohol fuel is “denatured alcohol” paint thinner (e.g. “SLX” brand) sold in hardware stores. This is mainly ethanol, which has been made undrinkable, often by adding some methanol to it. It is called “methylated spirits” in the U.K. Liquor (a renewable biofuel!) with very low water content, such as Everclear (190 proof = 95 % ethanol) can also be used in alcohol stoves. Ethanol has about 33% higher energy per gram for combustion than methanol, so it is a more efficient fuel to carry. Ethanol reported can put a plasticky coating on your pot bottom which is very hard to remove, so you might first want to coat your pot bottom with soap before using ethanol to keep that coating from sticking.
Gasoline or Coleman fuel should never be used. Also, isopropanol (“rubbing alcohol”; red bottle of HEET) is best avoided; it burns with yellow, sooty flame.
I wanted to better understand the world of alcohol stoves, so I read several on-line reviews and purchased four very different stoves that each had positive reviews by users. I also made a simple stove from a cat food can. I will briefly review these five stoves: the Brasslite Turbo II-D, the Gram Weenie Pro, the Thermojet, a SuperCat, and a Penny Stove. I conducted tests on them all, such as filling them with exactly 1 ounce (~30 ml) of methanol and timing how long the stove burned and how long it took to bring 2 cups ( 0.5 liter) of water to a boil in a 0.9 liter Primus LiTech aluminum pot (4.5 inch or 11.4 cm diameter) designed for camping. A typical backpacking dinner consists of a foil envelope of freeze-dried food, into which you pour 2 cups of boiling water, and then let it rehydrate for a few minutes to produce quite palatable meals. For some stoves I also loaded them with 1.25 oz methanol, and timed how long it took to bring 4 cups = 1 quart of water to boil in a kitchen saucepan with an outside diameter of 5.2 inches.
Brasslite Turbo II-D
The picture above shows the Brasslite Turbo II-D on the right, and Gram Weenie Pro on the left, with no fuel in them. In the photo are also two accessories I made for them, as explained below. The picture below shows them burning, with pots on them. The Turbo II-D has my “standard” 0.9 liter Primus pot, while the Gram Weenie Pro has my 0.6 liter Optimus Terra Solo pot.
The $32 Turbo II-D (2.8 oz / 80 g) is the largest of several models available from Brasslite. The stove’s designer, Aaron Rosenbloom, is a clinical psychologist (“It’s in my nature to help others feel better”), with a background in jewelry design. He has created a product that is handsome enough to grace a mantle, and also is effective at cooking. The stove consists of an inner cup that holds the alcohol, in an outer shell which has air inlet holes around the bottom and a central flame outlet hole on the top. A ring of stainless steel mesh on top supports the pot.
To operate the stove, you fill the inner cup, and also add a little fuel to the rim around the base, then light the inner part and the rim to help the stove warm or “prime”. You can put the pot on the stove immediately. The flame comes up through the central hole, and strengthens as the stove warms up and starts boiling up more alcohol.
An innovative feature of this stove is the “simmer ring”, which you can rotate to cover up some of the air holes in order to reduce the flame size. This can adjust the heat for controlled cooking, and of course save fuel. It does work quite well to control the flame. The problem is the simmer ring is sticky to move, and too hot to touch once the stove is heated. You have to pin the stove to the ground with the pot, then use something to poke at the tab on the simmer ring to get it to move. This is not user-friendly. However, I made a simmer-ring-pusher (in photo above) by bending a thick piece of wire, which enabled me to easily move the simmer ring. If the tab is at the 12-o’clock position, the ring-pusher can pull it to the right and simultaneously push in on the ring at the ~ 3-o’clock position, which helps skooch it along. Some high-temperature graphite-based lubricant might help here.
With this stove, air enters the holes around the bottom, flows up around the inner cup, and carries alcohol vapor out the hole on top, in a laminar flow. The flame under the pot can be seen in the picture above. It looks like there is a stagnant layer of air beneath the pot that is perhaps 0.25 inch (6 mm) thick, between the flame and the bottom of the pot, so heat transfer is not optimal, yet the flame covers the whole bottom of the pot. The Turbo II-D boiling times (see Tables 1 and 2 below) were about average.
Several other stoves have the same general design. The “12-10” burner that is used with a “Caldera cone” windscreen/pot holder is this type. Directions by Roy Robinson for making your own stove like this from two cat food cans are given here . His design, which includes a wick inside the inner cup, is known as the “cat stove.” More on the cat stove is here. The Featherfire stove is much like the Brasslite Turbo II-D, with a more convenient simmering adjustment, as reviewed in the Adventures In Stoving blog. Bottom line on the Turbo II-D: Elegant, average performance. The variable simmer is a bit balky, but is nice if you want do cooking other than boiling water.
Gram Weenie Pro
The Gram Weenie Pro (0.7 oz / 19 g) comes from End2End Trail Supply which is headed by George Carr. Other hikers on the internet have noted that George is a nice guy to deal with. The Gram Weenie Pro (in photos above) was the cheapest of the stoves I purchased and also the smallest and most robust. For $12.50, I got the stove, a small square of thickish aluminum foil to go under it, and a little plastic cup for measuring the fuel. As usual with these stoves, 1 ounce (30 ml) is the typical load. I also purchased from End2End some fuel bottles with neat closing spigots in the caps, and a thick foil windscreen. The stove is only 1.75 inches (4.4 cm) in diameter, and is made of fairly thick aluminum. You could stick it in your pocket without worry. It is a complete system, including pot support, though as usual with alcohol stoves you’d have to add some sort of windscreen. A long, folded-over piece of foil bent in a large circle will work for that.
To operate it, put the alcohol into the inner chamber. Some alcohol will flow into the outer annular chamber. Also dribble a little alcohol on the foil square that the stove sits on, and light it as well as the inner chamber. After a minute or less, the alcohol in the annular chamber will start to boil, and blue jets of flame will squirt out of the little side holes. It’s pretty impressive when seen for the first time. Then put the pot on top of the stove. This blocks fuel vapor from exiting from the central chamber, so all the flame is from the side jets. The photo above shows this stove burning, with a pot on it. As noted above, that is my small 0.6 liter pot, which is 3.75 inch diameter. The Gram Weenie Pro worked OK with this pot, though it took longer to get to boil (see table of boiling times below). This was the only one of the stoves I tested that would work well with such a small pot. The others had flames or pot stands that were too wide to handle this pot. Even with my 0.9 liter pot, with 11.4 cm diameter, most stoves had part of the flame spilling up the sides of the pot. If I get another pot, I’d get one that was lower and wider (e.g. 5″ = 12-13 cm for a 0.9 liter pot).
This stove took a little longer than most to boil, but maintained its flame the longest before burning out. Much of the flame action is below the pot, and only at the outer edges of the flame does it really contact the pot. There is no simmering option. Since its diameter is so narrow, it can be tippy with larger pots or if it is not on a smooth, level surface. I remedied this by making an auxiliary pot support out of “hardware cloth”, i.e. wire mesh with 0.5 inch wire spacing, and made just a hair shorter than the height of the stove. It can unhook at the ends and flatten out for storage. In use, this auxiliary pot support would encircle the stove, though in the photo above it is sitting behind the Gram Weenie Pro so as not to block the camera view.
Bottom line on the Gram Weenie Pro: Cheapest, smallest, and sturdiest. Potentially tippy. No simmering. Good for solo minimalist hiker, or as rugged spare stove.
This stove comes as a complete package: the alcohol burner plus a combination windscreen/pot stand, all weighing 2.5 oz. This is shown on the left in the photo below. On the right is a home-made “SuperCat” stove, which will be discussed later.
This next photo shows just the burner (lit) for the Thermojet on left, and the SuperCat stove burning on the right with a pot on it.
The Thermojet was the most convenient stove for outdoors use. To use it, you first assemble the windscreen by hooking its ends together to make a large cylinder, then insert two steel rods through holes in the sheet-metal to form the pot support. The stability of the windscreen/pot-stand was outstanding – -it made every other stove seem rickety by comparison. Its stability is similar to the Caldera Cone stove, which also has a wraparound windscreen/pot-stand.
The burner was very easy to use: just pour an ounce of fuel into the large central chamber, set it down in the midst of the windscreen, and light it. As with the Gram Weenie Pro, fuel flows into an outer chamber which has jets near the top. You can put the pot onto the pot-stand rods as soon as the burner is lit, and walk away to do other things. The burner is made of very thin aluminum and self-primes within about 30 seconds. A bunch of little flame jets shoot upward around the rim with good air mixing to help burn the vapors that also come up out of the central chamber.
The windscreen comes with an extra strip of sheet-metal wrapped around its outside. This “simmer ring” (not shown in the photo above) can be slid down to cover the main air intake holes at the base of the windscreen. This is supposed to restrict air flow enough to reduce flame size and fuel usage, for extended simmering. It would work if the stove were on a perfectly smooth surface (the manufacturer suggests carrying along a square of ¼” plywood to set the stove on, which is unappealing) and if your pot is big enough to nearly fill the top opening of the windscreen. But I found this simmer ring to be completely ineffective, and so have other reviewers on the internet. I was able to get a simmering effect by taking an empty small can (4.25 oz can of Hormel meat spread), turning it upside down, and punching some holes down low on the side to let air in, and in the center of what is now the top to let vapor/flame out. This restricted total air flow, and moved the flame further from the liquid fuel to reduce the heat transfer to the liquid and thus decrease the rate of vaporization. I don’t even bring the original “simmer ring” with me to the field. I do bring a small rectangle of folded foil to sit on the upwind side of the somewhat porous main windscreen to more fully block the wind. The windscreen can make it impossible to use a frying pan with its larger diameter and low handle.
The $40 Thermojet uses a special, thin, springy aluminum for the windscreen, and comes with a carry bag and a fuel bottle. Bottom line on Thermojet: Easiest to use, by far the most stable. This is what I bring for just boiling water or soup. May need to make an accessory can-with-holes to get simmering.
[2021 Postscript: It seems the Thermojet guy is not making these stoves anymore. Normally I prefer to support designesr by buying from them, rather than saving a few $$ by making my own copy of his concept, but in this case I suggest the reader consider making their own version using lightweight aluminum flashing and 1/16” steel rods from coat hangers or hardware store. I am guessing that a small Red Bull can or something like that was used for the actual themojet burner. It looks like a pretty typical soda can type, but smaller. Or…just buy a Caldera Cone sytem, which likewise integrates windscreen and pot support, and comes with matched alcohol stoves. ]
The simplest stove to make that I am aware of is the SuperCat stove designed by Jim Wood. His article gives complete explanations and building instructions, as well as discussion of safety with alcohol stoves. Here is another rave on this type of stove, with directions for making, by Andrew Skurka.
Pictures of my SuperCat are shown above. I started with a 3 oz aluminum can of Fancy Feast cat food. After removing the top, emptying the contents and washing it out, I used a simple paper punch to punch two rows of holes, spaced per Wood’s instructions. To use the stove, you pour in the alcohol, light it, give it 30 seconds to heat up, then place the pot directly on top of the can. The boiling alcohol will push vapor out the holes, creating a bunch of large, slow flame jets. This stove seemed a bit less efficient than the others (un-vigorous flame contact with pot, longer time to boil, shorter time till burnout), and seemed the most vulnerable to the slightest air currents (so would require very effective windscreen). However, it would do the job of boiling water for dinner and is something you could quickly make on the trail if needed. In a trail test, I found in a mild breeze and with a 3/4 circumference wind screen, this stove failed to boil 2 cups of water. I may try again with a 360 degree wind screen. In fairness, my pot diameter of 4.5 inches is probably just a little too small for this stove.
The “penny stove” is the brain-child of Mark Jurey. Jurey designs various stuff , including solar homes and low-impact landscapes. He has posted instructions for making the penny stove here. I was able to buy one pre-made but now you will have to make one yourself from one or two cans, or persuade someone else to make it for you. This might take an hour or two, if you have the tools but have never done it before.
The penny stove appears in the two photos above. The main part of the stove consists of a fuel cup piece, with a burner piece inserted in the top of it. The burner has six jet holes spaced around its rim, and (typically) four more holes drilled close together in the center, where they are covered by a penny. In the upper photo (stove unlit), the “simmer ring” is sitting to the left of the main part, the top / snuffer is behind and to the left. The lower photo shows it lit, with flame jets shooting upward.
To use it, remove the penny and pour fuel through the central holes into the fuel cup. Then cover these holes with the penny, pour more fuel on top of the burner plate, and light. The heat from the burning fuel on top will (if all goes well) eventually heat the alcohol in the bottom of the fuel cup enough to get it boiling, at which point six flame jets will shoot out the top of the burner plate. The penny serves as a kind of regulator – if the fuel boil-up gets excessive, it will push vapor up through the central holes and past the penny. This vapor will burn, but will not push much heat back down the walls of the fuel cup to the liquid fuel.
This burner requires a separate pot stand, which Jurey suggests making from two U-shaped rods, joined together with a piece of tubing. The penny stove I received had a pot-stand of this general type, made with thinner rod (copper-coated 3/32 inch steel). It has a little wobble, but does the job. The penny stove lends itself to placing the simmer ring on top of it to moderate the heat. This pushes the flame up off the fuel cup enough to slow heat transfer to the alcohol. All reviewers agree this simmer ring works well. The top piece can be used to extinguish the flame, and unused fuel can be easily poured out of this stove back into your fuel bottle.
This can be the most powerful of the five stoves reviewed here. The strong, upward-pointing jets make great contact with the pot bottom. On the other hand, it is the most complicated stove, with several pieces to keep track of. While the simmer ring works great, it can be tricky to get it on and off the stove without burning your fingers. Hiker joke: “How can you get the simmer rink onto your penny stove without burning your fingers?” Answer: “Ask your buddy to do it”.
The priming was iffy. Sometimes it does not come to full jetting, so you may have to (carefully) make sure the fuel on top has completely burned out, then add some more fuel and relight. If there is not a perfect seal between the fuel cup and the rim of the burner plate, alcohol vapor can squirt up between them making something of a flame-thrower; you can fix this by tapping/pulling out the burner plate, wiping a thin film of “J B Weld” high-temperature epoxy down inside the fuel cup where the burner plate seats, and replacing the burner. There is a sizeable vapor space in the fuel cup underneath the burner plate; if an alcohol/air mixture accumulates there before full priming, it can give a mild explosion and pop the burner plate off if it was not epoxied on. This can be prevented by completely filling the fuel cup all the way up to the burner plate before lighting it.
In the table below, I included two realistic extremes of performance with the penny stove. In one case, I tried to prime it by just letting the alcohol sitting above the burner plate burn. After a minute, this alcohol had burned out, but without starting up the jets. So I added more alcohol on top, re-lit, and this time the jets did start at about the two-minute mark. The times to boil were then about the same as times for the other stoves but with 2 minutes added, and it continued burning for a very long time.
In a second test, I took perhaps 10% of the 1 oz alcohol load and sprinkled it around the base of the stove, which was sitting on a piece of aluminum foil. After lighting this alcohol as well as the alcohol on top, I got large flame jets shooting out the top; because they were so hot, they put more heat into the stove and kept the fuel inside boiling vigorously, which (in a positive feedback loop) kept the flame jets large. In this mode, the water (see table below) boiled far faster than with any other stove, although the flame died out the soonest as well. The penny stove was a powerhouse in the test with 1 quart of water, where again I used alcohol at the base to prime it: it brought 1 quart to boil to a rolling boil in 7 min, then after I added the simmer ring, it continued to boil for 11 more minutes, for a total of 18 min burn on 1.25 ounce of fuel. Bottom line on penny stove: Can give outstanding performance, but takes more care than others to operate properly.
Later note on the penny stove: After the comparative stove testing was done, I realized why I had problems with priming it. In my comparisons, I was using only 1 or 1.25 oz of fuel, which left the dangerous (might explode) vapor space above the fuel in the stove and made it harder for the heat to get down to the fuel to get it evaporating.
The best, and only safe, way to operate this stove is to fill it all the way with fuel, so the alcohol just covers the penny but does not quite block the outer holes. This pool of alcohol on top of the stove is then lit, and burns long enough to get the stove going properly. This makes for easy, reliable start-ups. The slight disadvantage here is that, depending on the size of your penny stove, you may have to fill it with more fuel than you consume. Thus, after snuffing it and letting it cool, you have to pour the remaining alcohol into your fuel bottle. This is fine as long as your fuel bottle has a wide mouth.
[2021 Postscript: I saw a comment on the internet that rang true – – many folks agree that the penny stove is a superior performer, and ultralight. It once saved the day for me on a windy day when I did not have a great windscreen – – this jetted stove boiled my water when my SuperCat stove could not. However, the fussiness of using the penny stove causes most users to eventually leave it home in favor of simpler stoves. ]
Table 1. Results for test boiling 2 cups (0.5 l) water in 0.9 liter 4.5” diameter pot, using 1.0 oz methanol. Times in minutes:seconds.
Stove To start boil To Rolling boil Burnout
Turbo II-D 5:40 6:30 8:50
Gram Weenie Pro 5:50 7:00 10:40
(same, 0.6 l pot) 6:30 7:40 10:25
Thermojet 5:30 6:00 9:00
SuperCat 6:10 7:00 9:30
Penny [failed prime] 8:00 9:30 15:20
Penny [prime beneath] 4:30 5:00 8:00
The results of the main boiling test are shown in Table 1 above. Each stove does the job of boiling 2 cups of water. Below are results for heating 1 quart of water. The Turbo II-D and Gram Weenie Pro did not bring 1 quart to a full boil. For the penny stove, I added the simmer ring after rolling boil at 7 minutes, and continued a moderate boil till 18 minutes.
Table 2. Results for test boiling 4 cups = 1 quart (0.95 l) water in 5.2” diameter pot, using 1.25 oz methanol. Times in minutes.
Stove Start steaming To Rolling boil Burnout
Turbo II-D 10 NOT 11
Gram Weenie Pro 10 NOT 11
Thermojet 9 10 11
Penny [prime beneath] 4 7 18 (w/simmer ring)
Trangia Stove (not tested here) – This is a venerable alcohol burner, in production for over 50 years (shown below). Made of brass, it is a little heavy at 3.8 oz without windscreen or pot support, compared to the other stoves discussed here. However, it is sturdy and versatile, earning many favorable reviews. It is less prone to getting crushed than a stove made of soda cans. It come with a snuffing lid and a simmer ring that works well. Also, a lid with an o-ring that makes a seal on the top of the stove. Thus, you can fill it with alcohol at home, cap it, open it and cook with it, snuff it and recap it. All other stoves here require pouring in alcohol in the field, and pouring out any unconsumed alcohol back into the fuel storage bottle. (Over time, the seal on the cap can fail, so for long transport or storage it is advised to pour fuel back into the fuel bottle). Reportedly it can boil a liter of water in 8 minutes. Esbit and Solo and other brands make roughly equivalent stoves, with perhaps more convenient handles on the simmer plate.
Starlyte and Kojin Non-Spill Wick Stoves [2021 Postscript – not tested here]
A different type of stove has gotten some popularity in recent years. These stoves are basically a shallow cat food can, filled with some absorbent fiber batting. The batting holds the alcohol, so it does not spill out, even if the stove is tipped. This is a great safety and convenience factor. Both stoves come with a tight-fitting lid, so you can just snuff the stove, let it cool, cap it, and throw it in your pack, without pouring unused fuel back into a bottle.
The Starlyte stove is available here. It can have a built-in pot stand and is used with a variety of windscreens and stands. It seems that the Kojin stove is optimized for the Caldera Cone windscreen/pot support, since it needs a lot of space between the stove and the bottom of the pot. It boils 1-2 cups of water fast and with low fuel consumption. Comparisons on the internet suggest that the Kojin burns hotter/faster than the Starlyte, and the Kojin lid is more robust long term.
Safety With Alcohol Stoves
With alcohol stoves the flame is nearly silent, and is completely invisible in bright daylight. So always check for heat (slowly lower hand from above) before adding fresh fuel. And be mindful that if one of these little stoves is knocked over and the burning alcohol splashes out, there can suddenly be a sizeable pool of nearly invisible flames on things and on people.
Also, though I have not heard of it as a problem, it is possible that someone could mistake methanol (methyl alcohol or “wood alcohol”) with ethanol (ethyl alcohol or “grain alcohol”), and drink some. 1 to 4 oz (30-120 ml) of methanol can be fatal, and as little as 10 ml can cause permanent blindness. Over several hours, methanol migrates to the liver, where an enzyme metabolizes it to formic acid, which damages the nervous system. Drinking ethanol is an antidote – the ethanol preferentially binds to the enzyme, keeping it from converting the methanol.
If you want to cook some dish that needs to sit in near-boiling water for say 20 minutes, an alternative to trying to throttle down the flame of an alcohol stove is to use just enough fuel to get your pot boiling, then put some insulation on or around your pot to keep it hot. Just placing a hat on a pot can keep it warm for a while. Making a “pot cozy” out of closed-cell foam mat (directions here) can keep your meal warm for over an hour. For car camping, you can pour your rice and boiling water into a big thermos, and just let it stew in there without having to keep it simmering over a fire for half an hour.
The alcohol stoves and their light plastic fuel bottles are lighter than white gas or canister stoves. However, the energy density of alcohols is around 60% of Coleman fuel. Thus, you have to carry more alcohol fuel. Most comparisons find that an alcohol-based cooking system is lighter for trip that last less than two weeks, but after that the greater energy density gives petroleum stoves the edge. Some campers supplement their main petroleum stove with an alcohol stove as backup or a second burner.
The discussion here has focused on backpacking, but an alcohol stove may have a place in a general emergency preparedness kit. I read of a man on the U.S. Gulf Coast after a hurricane took out electricity and normal store deliveries for weeks. After all the local propane and Coleman fuel had been sold out, he was able to keep cooking with an alcohol stove, buying paint thinner that no one else was hoarding. Also, alcohol stoves are used on boats, because an alcohol fire can be readily doused with water.
Finally, since it is so easy to make your own alcohol stove, you can tinker away and try to improve on what is already out there. These stoves are fascinating from a technological point of view, since there are infinite variations that utilize the basic principles of heat transfer, mass transport, and chemical reaction. Some science and design principles are found here and here. Some gear-heads really get into this. For instance, Jim Babour owns over 100 backpacking stoves of all types, and posts several several times a month in his Adventures in Stoving blog. Here is a thread with lots of stovie talk. And this fellow confesses on YouTube to being addicted to making little alcohol burners, with two workbench tables filled with gear. Happy stoving!
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