Boiling 8 oz. 2X vs. 16 oz. 1X
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 Simon Wurster (Einstein) - F Locale: Big Apple Boiling 8 oz. 2X vs. 16 oz. 1X on 06/20/2010 11:38:03 MDT Assuming alcohol stove, 14-16 oz boiling water for meals, same vol. for hot beverage (using separate larger cup). Boil 8 oz, pour out, refill, boil next 8 oz. Assume 16 oz pot and 8 oz pot are the same diameter.Aside from wait times (con) and carrying a smaller/lighter pot (pro), are there any cons that would make this impractical? Is there an untapped fuel efficiency or glaring fuel inefficiency? Edited by Einstein on 06/20/2010 11:57:03 MDT.
 Bob Gross (--B.G.--) - F Locale: Silicon Valley Re: Boiling 8 oz. 2X vs. 16 oz. 1X on 06/20/2010 12:10:28 MDT Every alcohol stove is a little different, so it is impossible to say. Some are so tiny that bringing 8 oz. of water to boil is a big task. Some are so hot that 16 oz. or more is not a problem. Some are great when used in still air, but as soon as you have a good stiff breeze, they will get puny despite the windscreen. You have to test with your own stove to figure out what it will do.Besides the water in the pot, there are trade-offs with the dimensions of the pot within the windscreen. You have to test.Besides all that, you have to find the best type of alcohol.--B.G.-- Edited by --B.G.-- on 06/20/2010 12:11:08 MDT.
 James Byrnes (backfeets1) - M Locale: Midwest.... Missouri boil times.. on 06/20/2010 13:13:22 MDT There is a lag/preheat period for the stove to come up to speed plus the energy needed initially to heat the mass of the pot, and the lost heat in removing replacing the wind screen ect. Weather this is measurable in a practical sense??? I would guess you loose some fuel to the process.
 Simon Wurster (Einstein) - F Locale: Big Apple Re: boil times.. on 06/20/2010 13:59:20 MDT I guess the question "boils down" to this: are alcohol stoves typically optimized for 16 oz, and is the efficiency (with less volume) and inefficiency (with more volume) linear from this point? I've tried boiling more than 16 oz with dismal results, and had faster per-ounce boil times with 12-14 oz, so I was wondering--until I can fire up my stove next weekend--if anyone boils smaller volumes multiple times as a matter of course.
 Bob Gross (--B.G.--) - F Locale: Silicon Valley Re: Re: boil times.. on 06/20/2010 19:59:44 MDT Again, it varies from stove to stove. You need to test your own stove to see what you have. Some middle-of-the-road alcohol stoves seem to give good boil time performance for 16 ounces of water, but there are many much weaker than that and many much faster than that.There are several basic designs of alcohol stove. Some are optimized for fast boil times, but they use a lot of fuel. Some are specifically designed to be very economical on fuel, but they are fairly slow.You will see lots of variation just based on the type of alcohol you use. In general, denatured alcohol with high percentage of ethanol, or else almost-pure ethanol is what you seek for maximum heat to weight.--B.G.--
 Brad Groves (4quietwoods) - MLife Locale: Michigan Re: Boiling 8 oz. 2X vs. 16 oz. 1X on 06/22/2010 11:32:08 MDT It seems like I get better efficiency boiling one batch of water (to a point). I don't have numbers in front of me, or in my head right now for that matter, but it seems like I save a bit boiling one batch... Ie, if I boil ~28 ounces of water I use ~20-25ml of alcohol, but if I boil ~16oz I use ~15ml.
 Steven McAllister (brooklynkayak) - MLife Locale: Atlantic North East Re: Boiling 8 oz. 2X vs. 16 oz. 1X on 06/24/2010 12:44:02 MDT Also, some stoves have flames that shoot out the side. These can be less efficient with narrower pots and mugs as much of the flame can spread beyond the bottom.A tight windscreen can help keep the flame in close.My most efficient stove is also the slowest.
 Bob Gross (--B.G.--) - F Locale: Silicon Valley Re: Re: Boiling 8 oz. 2X vs. 16 oz. 1X on 06/24/2010 13:17:03 MDT "My most efficient stove is also the slowest."For many practical stoves, that is correct. A few people have teeny tiny stoves that are so slow and produce so little heat that they can't get a pot of water up to boiling point. So, with all that efficiency they shoot themselves in the foot.The bottom line is that each person must test and optimize their own stove, fuel, cook pot, and windscreen for their trips.--B.G.--
 Dan Durston (dandydan) - F Locale: IntoCascadia.com Boiling on 06/25/2010 04:53:09 MDT My FeatherFire alcohol stove boils 32oz for about 50% more fuel than it takes to boil 16oz, so it's much more efficient at 32oz. I imagine any alcohol stove would be more efficient with larger quantities up to a certain point where it can barely boil the water, and then the efficiency would drop off. I imagine most alcohol stoves can boil 16oz fairly easily, so doing 8oz x 2 would likely be less efficient with almost any alcohol stove.The nice thing with the FeatherFire is that you can adjust it with the simmer adjustment, so if you want increased efficiency you can turn it down and wait longer or vice versa. Edited by dandydan on 06/25/2010 04:54:01 MDT.
 Piper S. (sbhikes) - F Locale: Santa Barbara (Name: Diane) Re: Boiling 8 oz. 2X vs. 16 oz. 1X on 06/26/2010 08:13:32 MDT Being practical-minded rather than scientific, I would boil two 8oz batches of water if I were going to eat two different courses for dinner. I would boil one 16 oz batch of water if my dinner was a single course.Being only intuitively scientific, I would think that for any stove it would be more efficient fuel-wise to boil one 16 oz pot of water because that 2nd 8oz of water starts out warm, while with the 2 8oz pots, both start out cold.