## Jet Boil fuel question

Expand Messages
• How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods
Message 1 of 19 , Jun 1, 2011
How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods because I ran out of fuel. :)

Ewa
• On Wed, Jun 1, 2011 at 6:14 AM, Ewa Bialkowski wrote: How much extra fuel would you think I need to bring to account for altitude and
Message 2 of 19 , Jun 1, 2011
On Wed, Jun 1, 2011 at 6:14 AM, Ewa Bialkowski wrote:

How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods because I ran out of fuel. :)

I'm not sure you need to bring any.  While fuel is less efficient at higher altitudes and your starting water is colder that the REI test protocol, the boiling point is also lower at higher elevations (193 degrees at 10k feet).  I'd guess in the 0 to 10% range.  My experience at altitude has been that I can cook 24 one-person meals (with a fair amount of steeping and re-simmering) in a JetBoil PCS on a 110 gram container.  And most of those "tests" have been at altitude with cold water.

REI tests -- if memory serves --  heated 11 L of water with 100 grams of fuel with water going from 60 degrees to 212 (150 degree gain).  From 35 to 193 would be a 158 degree gain (5% more gain).  And in the added range of temps (from 35 to 60 degrees) you wouldn't be losing much, if any, heat to the surrounding air.

That said, I start with pre-warmed water when I can, if I'm on a trip where I am stretching my fuel capacity to the limit. I put a partly full water bottle in the sleeping bag overnight and use it for breakfast.  And I have a water bottle wrapped in black tape that will warm up (some) in the sun before dinner.

1616 Castro Street
San Francisco, CA  94114-3707
415-648-9279

• I doubt many of you would want to buy one. but I was shocked to see a Svea 123 stove for sale at one of the local stores last week.
Message 3 of 19 , Jun 1, 2011
I doubt many of you would want to buy one. but I was shocked to see a Svea 123 stove for sale at one of the local stores last week.

To: johnmuirtrail@yahoogroups.com
Sent: Wed, June 1, 2011 10:03:32 AM
Subject: Re: [John Muir Trail] Jet Boil fuel question

On Wed, Jun 1, 2011 at 6:14 AM, Ewa Bialkowski wrote:

How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods because I ran out of fuel. :)

I'm not sure you need to bring any.  While fuel is less efficient at higher altitudes and your starting water is colder that the REI test protocol, the boiling point is also lower at higher elevations (193 degrees at 10k feet).  I'd guess in the 0 to 10% range.  My experience at altitude has been that I can cook 24 one-person meals (with a fair amount of steeping and re-simmering) in a JetBoil PCS on a 110 gram container.  And most of those "tests" have been at altitude with cold water.

REI tests -- if memory serves --  heated 11 L of water with 100 grams of fuel with water going from 60 degrees to 212 (150 degree gain).  From 35 to 193 would be a 158 degree gain (5% more gain).  And in the added range of temps (from 35 to 60 degrees) you wouldn't be losing much, if any, heat to the surrounding air.

That said, I start with pre-warmed water when I can, if I'm on a trip where I am stretching my fuel capacity to the limit. I put a partly full water bottle in the sleeping bag overnight and use it for breakfast.  And I have a water bottle wrapped in black tape that will warm up (some) in the sun before dinner.

1616 Castro Street
San Francisco, CA  94114-3707
415-648-9279

• God, they are pretty Loved mine and used it for years [image: 240px-Svea_123R.jpg] More info than you d ever want at http://en.wikipedia.org/wiki/Svea_123 I
Message 4 of 19 , Jun 1, 2011
God, they are pretty

Loved mine and used it for years

http://en.wikipedia.org/wiki/Svea_123

I will cede my small share of traditionalist-in-chief title to anyone who carries it.

May not be safe to re-light it while still hot, so it is hard to use with the simmer-and-steep cooking I have come to prefer.

1616 Castro Street
San Francisco, CA  94114-3707
415-648-9279

On Wed, Jun 1, 2011 at 8:08 AM, Kim Fishburn wrote:

I doubt many of you would want to buy one. but I was shocked to see a Svea 123 stove for sale at one of the local stores last week.

To: johnmuirtrail@yahoogroups.com
Sent: Wed, June 1, 2011 10:03:32 AM
Subject: Re: [John Muir Trail] Jet Boil fuel question

On Wed, Jun 1, 2011 at 6:14 AM, Ewa Bialkowski wrote:

How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods because I ran out of fuel. :)

I'm not sure you need to bring any.  While fuel is less efficient at higher altitudes and your starting water is colder that the REI test protocol, the boiling point is also lower at higher elevations (193 degrees at 10k feet).  I'd guess in the 0 to 10% range.  My experience at altitude has been that I can cook 24 one-person meals (with a fair amount of steeping and re-simmering) in a JetBoil PCS on a 110 gram container.  And most of those "tests" have been at altitude with cold water.

REI tests -- if memory serves --  heated 11 L of water with 100 grams of fuel with water going from 60 degrees to 212 (150 degree gain).  From 35 to 193 would be a 158 degree gain (5% more gain).  And in the added range of temps (from 35 to 60 degrees) you wouldn't be losing much, if any, heat to the surrounding air.

That said, I start with pre-warmed water when I can, if I'm on a trip where I am stretching my fuel capacity to the limit. I put a partly full water bottle in the sleeping bag overnight and use it for breakfast.  And I have a water bottle wrapped in black tape that will warm up (some) in the sun before dinner.

1616 Castro Street
San Francisco, CA  94114-3707
415-648-9279

• There used to be a guy at the Berkeley REI that had a scared face from a fire. I was told it was from a Svea 123 exploding. Its something that could happen
Message 5 of 19 , Jun 1, 2011
There used to be a guy at the Berkeley REI that had a scared face from a fire. I was told it was from a Svea 123 exploding. Its something that could happen with a lot of stoves if not used properly.

Kim

P.S. Remember those days when the Berkeley REI was the only REI in Northern CA? The days when they had a sale there was a line the length of the side of the building waiting for someone to leave so they could get in. The line for the cash registers was about 100 ft long and the last person held a pole with a sign on it that said "Line Forms Here," and they had 23 (I counted them) cash registers going. At least the line moved fast. They'd never be able to have a sale that than anymore. They had so many racks out someone in a wheel chair wouldn't have been able to get around. I even had trouble squeezing between some of the racks of clothing.

To: johnmuirtrail@yahoogroups.com
Sent: Wed, June 1, 2011 10:22:13 AM
Subject: Re: [John Muir Trail] Svea 123 Stove

God, they are pretty

Loved mine and used it for years

http://en.wikipedia.org/wiki/Svea_123

I will cede my small share of traditionalist-in-chief title to anyone who carries it.

May not be safe to re-light it while still hot, so it is hard to use with the simmer-and-steep cooking I have come to prefer.

1616 Castro Street
San Francisco, CA  94114-3707
415-648-9279

On Wed, Jun 1, 2011 at 8:08 AM, Kim Fishburn wrote:

I doubt many of you would want to buy one. but I was shocked to see a Svea 123 stove for sale at one of the local stores last week.

To: johnmuirtrail@yahoogroups.com
Sent: Wed, June 1, 2011 10:03:32 AM
Subject: Re: [John Muir Trail] Jet Boil fuel question

On Wed, Jun 1, 2011 at 6:14 AM, Ewa Bialkowski wrote:

How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods because I ran out of fuel. :)

I'm not sure you need to bring any.  While fuel is less efficient at higher altitudes and your starting water is colder that the REI test protocol, the boiling point is also lower at higher elevations (193 degrees at 10k feet).  I'd guess in the 0 to 10% range.  My experience at altitude has been that I can cook 24 one-person meals (with a fair amount of steeping and re-simmering) in a JetBoil PCS on a 110 gram container.  And most of those "tests" have been at altitude with cold water.

REI tests -- if memory serves --  heated 11 L of water with 100 grams of fuel with water going from 60 degrees to 212 (150 degree gain).  From 35 to 193 would be a 158 degree gain (5% more gain).  And in the added range of temps (from 35 to 60 degrees) you wouldn't be losing much, if any, heat to the surrounding air.

That said, I start with pre-warmed water when I can, if I'm on a trip where I am stretching my fuel capacity to the limit. I put a partly full water bottle in the sleeping bag overnight and use it for breakfast.  And I have a water bottle wrapped in black tape that will warm up (some) in the sun before dinner.

1616 Castro Street
San Francisco, CA  94114-3707
415-648-9279

• Interesting about water temperature. I ve never thought much about it. Most of the time it feels like it just came off a chunk of ice unless it s from a
Message 6 of 19 , Jun 1, 2011

Interesting about water temperature.  I've never thought much about it.  Most of the time it feels like it just came off a chunk of ice unless it's from a lake. This is something I'll have to study on the trail this year--water temps.
But enough of the silly mental musings.
This blatantly stolen quip comes from a study on the subject and may shed light on your question.

## How Does Altitude Affect Cooking Time and Fuel Consumption?

As you ascend in elevation, atmospheric pressure decreases and water boils at a lower temperature. For every 18 °F drop in the boiling point of water, it doubles the time to cook food. For example, the boiling point of water drops from 212 °F at sea level to 194 °F at 10,000 feet. It takes twice as long to cook raw food at 10,000 feet than it does at sea level. So, if you are planning to cook raw food at higher elevations, be sure to bring extra fuel. For boiling water and rehydrating foods, altitude doesn't make much difference. It actually takes a little less time and fuel to boil water (since it boils at a lower temperature), but rehydration will take a little longer, which balances it out.

To: johnmuirtrail@yahoogroups.com
From: ewa.bialkowski@...
Date: Wed, 1 Jun 2011 06:14:53 -0700
Subject: [John Muir Trail] Jet Boil fuel question

How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods because I ran out of fuel. :)

Ewa

• So...additional question on jet boil...I m considering a jet boil (Sol Ti) (8.5 oz) as opposed to my Snowpeak Giga Power Stove with Piezo (3.75 oz) for the
Message 7 of 19 , Jun 1, 2011
So...additional question on jet boil...I'm considering a jet boil (Sol Ti) (8.5 oz) as opposed to my Snowpeak  Giga Power Stove with Piezo (3.75 oz) for the advantage of bringing less fuel.  Are the .9 oz stabilizers necessary?  And the pot support?  Is that just if you use a pot instead of the cup that comes with?

Is everybody's experience more or less the same--24 one-person meals out of a 110 gram containerwith steeping and starting with pre-warmed water when possible ?  My longest resupply is 8 days, and since I don't cook breakfast, or lunch, I figure the most I will actually need is 8 one person meals. (rehydrate/steep)...so should have plenty to spare...shouldn't need more than 2  (110g) containers for my whole trip (29 days).  Does that sound right?

Cheryl
"Xtra Credit"

In a message dated 6/1/2011 8:03:56 A.M. Pacific Daylight Time, johnladd@... writes:

How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods because I ran out of fuel. :)

I'm not sure you need to bring any.  While fuel is less efficient at higher altitudes and your starting water is colder that the REI test protocol, the boiling point is also lower at higher elevations (193 degrees at 10k feet).  I'd guess in the 0 to 10% range.  My experience at altitude has been that I can cook 24 one-person meals (with a fair amount of steeping and re-simmering) in a JetBoil PCS on a 110 gram container.  And most of those "tests" have been at altitude with cold water.

• ... Until I knew my personal results, I tended to bring a spare. You have to be quite careful about fuel consumption to get 24 meals from 110 grams. I.e., no
Message 8 of 19 , Jun 1, 2011
On Wed, Jun 1, 2011 at 10:57 AM, wrote:

Is everybody's experience more or less the same--24 one-person meals out of a 110 gram container with steeping and starting with pre-warmed water when possible ?  My longest resupply is 8 days, and since I don't cook breakfast, or lunch, I figure the most I will actually need is 8 one person meals. (rehydrate/steep)...so should have plenty to spare...shouldn't need more than 2  (110g) containers for my whole trip (29 days).  Does that sound right?

Until I knew my personal results, I tended to bring a spare.  You have to be quite careful about fuel consumption to get 24 meals from 110 grams.  I.e., no extra water for tea or for cleaning, and never let anything just sit there boiling or simmering.  Turn it off as soon as it comes to a bare simmer.  (After the simmer, you aren't using fuel to heat water any more, just using it to turn water into more steam).

But that said, if you are only need to bringing (say) 16 oz of water to a simmer and then immediately pour it into something like a bag where it will steep (or pour the dehydrated food into the pot) and not doing any extended simmering, re-heating or re-steeping, you should get something exceeding 24 days on a single container, so that your second canister won't come out until you are starting to approach Whitney.  29 days times 16 oz equals 464 oz. of water which equals 13.7 liters.  Since REI says you can simmer 11 L in various JetBoil versions per 100 grams (if that is the right number for your stove) you will need only 124 grams of fuel, or just over the first 110 gram container.

(Note: I don't use freeze-dried or similar foods, so I'm making an assumption here that the kinds of directions I see on the packages -- typically something like pour hot water into a bag ans wait -- actually work in practice.)

But you do need to be careful.  The one time I ran out of fuel with a canister stove was when I couldn't buy a 110 or 100 gram canister at TM (they were out) and I bought a 200 or 220.  I thought I had lots of fuel to spare, since I was on a 7-day leg, so started splurging by heating water to wash up, hot water to sip, etc.  Ran out with my last breakfast 3.4 cooked.  My fuel consumption rate must have tripled.

Results vary so much that the only way to know for sure is weighing a fuel canister before and after x days of travel under similar conditions.  Divide the weight loss on the canister by the number of days and you get your consumption rate per day -- in ozs. or grams (1 oz = 28.3 grams).  Since your fuel consumption may be as little as an oz. per week, at the way you are cooking, you need a pretty accurate scale (which you can often find in a post office).  You could just test it at home, starting with ice water and simmering, say, 16 oz. 10 times over and then re-weighing the canister.

John
• I don t need the pot support, it s for using a pot other than the Jetboil pot I think. Nor do I use the stabilizer; after all I don t use one or my snow peak
Message 9 of 19 , Jun 1, 2011
I don't need the pot support, it's for using a pot other than the Jetboil pot I think.  Nor do I use the stabilizer; after all I don't use one or my snow peak giga power cannister either. It's a nice touch tho if you're not counting ozs. So, the stove, pot, and pot  kid come to 8.5 ozs, and the cover/cup for the bottom of the pot another oz.  The stabilizer and pot support come included tho.

Barbara

On Jun 1, 2011, at 10:57 AM, Calbirder@... wrote:

So...additional question on jet boil...I'm considering a jet boil (Sol Ti) (8.5 oz) as opposed to my Snowpeak  Giga Power Stove with Piezo (3.75 oz) for the advantage of bringing less fuel.  Are the .9 oz stabilizers necessary?  And the pot support?  Is that just if you use a pot instead of the cup that comes with?

Is everybody's experience more or less the same--24 one-person meals out of a 110 gram containerwith steeping and starting with pre-warmed water when possible ?  My longest resupply is 8 days, and since I don't cook breakfast, or lunch, I figure the most I will actually need is 8 one person meals. (rehydrate/steep)...so should have plenty to spare...shouldn't need more than 2  (110g) containers for my whole trip (29 days).  Does that sound right?

Cheryl
"Xtra Credit"

In a message dated 6/1/2011 8:03:56 A.M. Pacific Daylight Time, johnladd@... writes:

How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods because I ran out of fuel. :)

I'm not sure you need to bring any.  While fuel is less efficient at higher altitudes and your starting water is colder that the REI test protocol, the boiling point is also lower at higher elevations (193 degrees at 10k feet).  I'd guess in the 0 to 10% range.  My experience at altitude has been that I can cook 24 one-person meals (with a fair amount of steeping and re-simmering) in a JetBoil PCS on a 110 gram container.  And most of those "tests" have been at altitude with cold water.

• Same as John. I still have mine in a trunk somewhere. To pretty to dump. From: johnmuirtrail@yahoogroups.com [mailto:johnmuirtrail@yahoogroups.com] On Behalf
Message 10 of 19 , Jun 1, 2011

Same as John.  I still have mine in a trunk somewhere.  To pretty to dump.

From: johnmuirtrail@yahoogroups.com [mailto:johnmuirtrail@yahoogroups.com] On Behalf Of John Ladd
Sent: Wednesday, June 01, 2011 8:22 AM
To: johnmuirtrail@yahoogroups.com
Subject: Re: [John Muir Trail] Svea 123 Stove

God, they are pretty

Loved mine and used it for years

http://en.wikipedia.org/wiki/Svea_123

I will cede my small share of traditionalist-in-chief title to anyone who carries it.

May not be safe to re-light it while still hot, so it is hard to use with the simmer-and-steep cooking I have come to prefer.

1616 Castro Street
San Francisco, CA  94114-3707
415-648-9279

On Wed, Jun 1, 2011 at 8:08 AM, Kim Fishburn <outhiking_55@...> wrote:

I doubt many of you would want to buy one. but I was shocked to see a Svea 123 stove for sale at one of the local stores last week.

To: johnmuirtrail@yahoogroups.com
Sent: Wed, June 1, 2011 10:03:32 AM
Subject: Re: [John Muir Trail] Jet Boil fuel question

On Wed, Jun 1, 2011 at 6:14 AM, Ewa Bialkowski <ewa.bialkowski@...> wrote:

How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods because I ran out of fuel. :)

I'm not sure you need to bring any.  While fuel is less efficient at higher altitudes and your starting water is colder that the REI test protocol, the boiling point is also lower at higher elevations (193 degrees at 10k feet).  I'd guess in the 0 to 10% range.  My experience at altitude has been that I can cook 24 one-person meals (with a fair amount of steeping and re-simmering) in a JetBoil PCS on a 110 gram container.  And most of those "tests" have been at altitude with cold water.

REI tests -- if memory serves --  heated 11 L of water with 100 grams of fuel with water going from 60 degrees to 212 (150 degree gain).  From 35 to 193 would be a 158 degree gain (5% more gain).  And in the added range of temps (from 35 to 60 degrees) you wouldn't be losing much, if any, heat to the surrounding air.

That said, I start with pre-warmed water when I can, if I'm on a trip where I am stretching my fuel capacity to the limit. I put a partly full water bottle in the sleeping bag overnight and use it for breakfast.  And I have a water bottle wrapped in black tape that will warm up (some) in the sun before dinner.

1616 Castro Street
San Francisco, CA  94114-3707
415-648-9279

• John, thank you so much for your advice. I ve been battling the question of boots vs trail runners for weeks now. For the past 3 years I ve been backpacking in
Message 11 of 19 , Jun 1, 2011
John, thank you so much for your advice. I've been battling the question of boots vs trail runners for weeks now. For the past 3 years I've been backpacking in very light footwear with no problems at all. This year's conditions made me reconsider. I have tried hiking and backpacking at least 4 different pairs of boots, which in the store felt super comfortable but after a few hours on the trail became unbearable to wear. (love REI for their patience with me) I am not giving up hope yet but I am getting a bit discouraged by how my feet react to heavier footwear.
Thanks again.

Ewa

On Wed, Jun 1, 2011 at 10:57 AM, wrote:

Is everybody's experience more or less the same--24 one-person meals out of a 110 gram container with steeping and starting with pre-warmed water when possible ?  My longest resupply is 8 days, and since I don't cook breakfast, or lunch, I figure the most I will actually need is 8 one person meals. (rehydrate/steep)...so should have plenty to spare...shouldn't need more than 2  (110g) containers for my whole trip (29 days).  Does that sound right?

Until I knew my personal results, I tended to bring a spare.  You have to be quite careful about fuel consumption to get 24 meals from 110 grams.  I.e., no extra water for tea or for cleaning, and never let anything just sit there boiling or simmering.  Turn it off as soon as it comes to a bare simmer.  (After the simmer, you aren't using fuel to heat water any more, just using it to turn water into more steam).

But that said, if you are only need to bringing (say) 16 oz of water to a simmer and then immediately pour it into something like a bag where it will steep (or pour the dehydrated food into the pot) and not doing any extended simmering, re-heating or re-steeping, you should get something exceeding 24 days on a single container, so that your second canister won't come out until you are starting to approach Whitney.  29 days times 16 oz equals 464 oz. of water which equals 13.7 liters.  Since REI says you can simmer 11 L in various JetBoil versions per 100 grams (if that is the right number for your stove) you will need only 124 grams of fuel, or just over the first 110 gram container.

(Note: I don't use freeze-dried or similar foods, so I'm making an assumption here that the kinds of directions I see on the packages -- typically something like pour hot water into a bag ans wait -- actually work in practice.)

But you do need to be careful.  The one time I ran out of fuel with a canister stove was when I couldn't buy a 110 or 100 gram canister at TM (they were out) and I bought a 200 or 220.  I thought I had lots of fuel to spare, since I was on a 7-day leg, so started splurging by heating water to wash up, hot water to sip, etc.  Ran out with my last breakfast 3.4 cooked.  My fuel consumption rate must have tripled.

Results vary so much that the only way to know for sure is weighing a fuel canister before and after x days of travel under similar conditions.  Divide the weight loss on the canister by the number of days and you get your consumption rate per day -- in ozs. or grams (1 oz = 28.3 grams).  Since your fuel consumption may be as little as an oz. per week, at the way you are cooking, you need a pretty accurate scale (which you can often find in a post office).  You could just test it at home, starting with ice water and simmering, say, 16 oz. 10 times over and then re-weighing the canister.

John

• Cheryl: I played with mine on the back patio (it s new to me too) and it seemed a bit top heavy without the stabilizers. Also when I packed it up with the 110
Message 12 of 19 , Jun 1, 2011

Cheryl:

I played with mine on the back patio (it’s new to me too) and it seemed a bit top heavy without the stabilizers.  Also when I packed it up with the 110 gm canister in it the canister rattled around without the pot support to center and hold it.  I might put an extra paper towel around it instead to cut the noise and give me the extra clean up towel.

I am also interested in the fuel life.  I am currently planning three canisters for 23 days but base on what you guys are saying maybe one and one at my drop at Charlotte Lake RS would be fine or overkill.  I also only do Freeze dried and Mac and Cheese.

Joe

From: johnmuirtrail@yahoogroups.com [mailto:johnmuirtrail@yahoogroups.com] On Behalf Of Calbirder@...
Sent: Wednesday, June 01, 2011 10:58 AM
To: johnmuirtrail@yahoogroups.com
Subject: Re: [John Muir Trail] Jet Boil fuel question

So...additional question on jet boil...I'm considering a jet boil (Sol Ti) (8.5 oz) as opposed to my Snowpeak  Giga Power Stove with Piezo (3.75 oz) for the advantage of bringing less fuel.  Are the .9 oz stabilizers necessary?  And the pot support?  Is that just if you use a pot instead of the cup that comes with?

Is everybody's experience more or less the same--24 one-person meals out of a 110 gram containerwith steeping and starting with pre-warmed water when possible ?  My longest resupply is 8 days, and since I don't cook breakfast, or lunch, I figure the most I will actually need is 8 one person meals. (rehydrate/steep)...so should have plenty to spare...shouldn't need more than 2  (110g) containers for my whole trip (29 days).  Does that sound right?

Cheryl

"Xtra Credit"

In a message dated 6/1/2011 8:03:56 A.M. Pacific Daylight Time, johnladd@... writes:

How much extra fuel would you think I need to bring to account for altitude and very cold water? 10%, 20% I would hate to have to eat dry freeze dried foods because I ran out of fuel. :)

I'm not sure you need to bring any.  While fuel is less efficient at higher altitudes and your starting water is colder that the REI test protocol, the boiling point is also lower at higher elevations (193 degrees at 10k feet).  I'd guess in the 0 to 10% range.  My experience at altitude has been that I can cook 24 one-person meals (with a fair amount of steeping and re-simmering) in a JetBoil PCS on a 110 gram container.  And most of those "tests" have been at altitude with cold water.

• Have you tried Lowa brand? I am on my 2nd pair of Renegades, but they also do a lower (lol) boot. I find them comfy out of the box, and I have major feet
Message 13 of 19 , Jun 1, 2011
Have you tried Lowa brand?  I am on my 2nd pair of Renegades, but they also do a lower (lol) boot.  I find them comfy out of the box, and I have major feet issues (surgery, bunions, neuromas , ick!).  Vasque were too narrow, Keens and Merrill I could feel every little pepple.  I've heard Montrail are good but ntvsure if REI sells the.  A 16 does. Good luck,

Barbara

On Jun 1, 2011, at 12:21 PM, Ewa <ewa.bialkowski@...> wrote:

John, thank you so much for your advice. I've been battling the question of boots vs trail runners for weeks now. For the past 3 years I've been backpacking in very light footwear with no problems at all. This year's conditions made me reconsider. I have tried hiking and backpacking at least 4 different pairs of boots, which in the store felt super comfortable but after a few hours on the trail became unbearable to wear. (love REI for their patience with me) I am not giving up hope yet but I am getting a bit discouraged by how my feet react to heavier footwear.
Thanks again.

Ewa

On Wed, Jun 1, 2011 at 10:57 AM, wrote:

Is everybody's experience more or less the same--24 one-person meals out of a 110 gram container with steeping and starting with pre-warmed water when possible ?  My longest resupply is 8 days, and since I don't cook breakfast, or lunch, I figure the most I will actually need is 8 one person meals. (rehydrate/steep)...so should have plenty to spare...shouldn't need more than 2  (110g) containers for my whole trip (29 days).  Does that sound right?

Until I knew my personal results, I tended to bring a spare.  You have to be quite careful about fuel consumption to get 24 meals from 110 grams.  I.e., no extra water for tea or for cleaning, and never let anything just sit there boiling or simmering.  Turn it off as soon as it comes to a bare simmer.  (After the simmer, you aren't using fuel to heat water any more, just using it to turn water into more steam).

But that said, if you are only need to bringing (say) 16 oz of water to a simmer and then immediately pour it into something like a bag where it will steep (or pour the dehydrated food into the pot) and not doing any extended simmering, re-heating or re-steeping, you should get something exceeding 24 days on a single container, so that your second canister won't come out until you are starting to approach Whitney.  29 days times 16 oz equals 464 oz. of water which equals 13.7 liters.  Since REI says you can simmer 11 L in various JetBoil versions per 100 grams (if that is the right number for your stove) you will need only 124 grams of fuel, or just over the first 110 gram container.

(Note: I don't use freeze-dried or similar foods, so I'm making an assumption here that the kinds of directions I see on the packages -- typically something like pour hot water into a bag ans wait -- actually work in practice.)

But you do need to be careful.  The one time I ran out of fuel with a canister stove was when I couldn't buy a 110 or 100 gram canister at TM (they were out) and I bought a 200 or 220.  I thought I had lots of fuel to spare, since I was on a 7-day leg, so started splurging by heating water to wash up, hot water to sip, etc.  Ran out with my last breakfast 3.4 cooked.  My fuel consumption rate must have tripled.

Results vary so much that the only way to know for sure is weighing a fuel canister before and after x days of travel under similar conditions.  Divide the weight loss on the canister by the number of days and you get your consumption rate per day -- in ozs. or grams (1 oz = 28.3 grams).  Since your fuel consumption may be as little as an oz. per week, at the way you are cooking, you need a pretty accurate scale (which you can often find in a post office).  You could just test it at home, starting with ice water and simmering, say, 16 oz. 10 times over and then re-weighing the canister.

John

• My Jetboil experience (JMT 2009 and 2010): I go by quarts of water boiled -- 25+ quarts = 250gram container -- have not used the 110 gram container but to be
Message 14 of 19 , Jun 1, 2011
My Jetboil experience (JMT 2009 and 2010):

I go by quarts of water boiled -- 25+ quarts =  250gram container -- have not used the 110 gram container but to be safe I would allow for 10+ quarts.

Bruce

On Wed, Jun 1, 2011 at 12:37 PM, John Ladd wrote:

On Wed, Jun 1, 2011 at 10:57 AM, wrote:

Is everybody's experience more or less the same--24 one-person meals out of a 110 gram container with steeping and starting with pre-warmed water when possible ?  My longest resupply is 8 days, and since I don't cook breakfast, or lunch, I figure the most I will actually need is 8 one person meals. (rehydrate/steep)...so should have plenty to spare...shouldn't need more than 2  (110g) containers for my whole trip (29 days).  Does that sound right?

Until I knew my personal results, I tended to bring a spare.  You have to be quite careful about fuel consumption to get 24 meals from 110 grams.  I.e., no extra water for tea or for cleaning, and never let anything just sit there boiling or simmering.  Turn it off as soon as it comes to a bare simmer.  (After the simmer, you aren't using fuel to heat water any more, just using it to turn water into more steam).

But that said, if you are only need to bringing (say) 16 oz of water to a simmer and then immediately pour it into something like a bag where it will steep (or pour the dehydrated food into the pot) and not doing any extended simmering, re-heating or re-steeping, you should get something exceeding 24 days on a single container, so that your second canister won't come out until you are starting to approach Whitney.  29 days times 16 oz equals 464 oz. of water which equals 13.7 liters.  Since REI says you can simmer 11 L in various JetBoil versions per 100 grams (if that is the right number for your stove) you will need only 124 grams of fuel, or just over the first 110 gram container.

(Note: I don't use freeze-dried or similar foods, so I'm making an assumption here that the kinds of directions I see on the packages -- typically something like pour hot water into a bag ans wait -- actually work in practice.)

But you do need to be careful.  The one time I ran out of fuel with a canister stove was when I couldn't buy a 110 or 100 gram canister at TM (they were out) and I bought a 200 or 220.  I thought I had lots of fuel to spare, since I was on a 7-day leg, so started splurging by heating water to wash up, hot water to sip, etc.  Ran out with my last breakfast 3.4 cooked.  My fuel consumption rate must have tripled.

Results vary so much that the only way to know for sure is weighing a fuel canister before and after x days of travel under similar conditions.  Divide the weight loss on the canister by the number of days and you get your consumption rate per day -- in ozs. or grams (1 oz = 28.3 grams).  Since your fuel consumption may be as little as an oz. per week, at the way you are cooking, you need a pretty accurate scale (which you can often find in a post office).  You could just test it at home, starting with ice water and simmering, say, 16 oz. 10 times over and then re-weighing the canister.

John

• ... This law is on shaky grounds. Have you dug into the reasoning behind it? Or are you merely reposting what you read, without giving the source.
Message 15 of 19 , Jun 1, 2011
--- In johnmuirtrail@yahoogroups.com, Don Amundson <amrowinc@...> wrote:
>
>
>

> But enough of the silly mental musings.
> This blatantly stolen quip comes from a study on the subject and may shed light on your question.
>
> How Does Altitude Affect Cooking Time and Fuel Consumption?
> As you ascend in elevation, atmospheric pressure decreases and water
> boils at a lower temperature. For every 18 ï¿½F drop in the boiling point
> of water, it doubles the time to cook food. For example, the boiling
> point of water drops from 212 ï¿½F at sea level to 194 ï¿½F at 10,000 feet.
> It takes twice as long to cook raw food at 10,000 feet than it does at
> sea level.

This "law" is on shaky grounds. Have you dug into the reasoning behind it? Or are you merely reposting what you read, without giving the source.

http://www.rod.beavon.clara.net/Q10.htm
------------------------------- Quote ----------------------
"Q10 â" rubber-stamp âthinkingâ.

âReaction rates double for every 10C rise in temperatureâ â" I expect that youâve heard this statement. It is, for some reason, very popular with those studying biology; it is there that you find Q10, the ratio of reaction rate at temperature T to that at T + 10. The doubling is usually offered as a fact of chemical (or biochemical) life; such a pity, then, that it isnât true.

As originally promulgated in university texts it was âReaction rates roughly double or tripleâ¦â; but in the (ever-increasing) sanitising found in A level texts a number of fairly important words were jettisoned. Like âroughlyâ, âdouble or tripleâ. (Yes, guilty; if youâve read my Nelson texts there are numerous omissions there, and no, I donât like that.) A number of other important caveats disappeared too, so letâs examine the ideas further."
---------------- End Quote ---------------------------

He then goes into details of the Arrhenius equation from which one can attempt to derive the conditions under which a 10 degree (Centigrade) temperature change will double the reaction rate..

Note that the original intent of the academic quote was to give a "Rule of Thumb" ( "roughly", "double or tripple the rate" ) which is requoted here as a "RULE OF ABSOLUTES". Just like one would expect of someone who never read the original, nor sensed the meaning of the original text.

http://antoine.frostburg.edu/chem/senese/101/kinetics/faq/temperature-and-reaction-rate.shtml

Does a 10Â°C temperature rise double reaction rates? [10C=18F]

This web page provides the basic equations and a calculator for reaction rate doubling using the standard Arrhenius Reaction Rate relationship.

Something called the "Activation Energy" for the substance reacting must have a specific value for the "Doubling every 10C (18F)" to occur.

Does your food have these requirements met? Have you ever inquired about the activation energy involved in cooking? But you quote a result based upon a specific activation energy.

Well, no. Did you know that cooking proteins often involves denaturing, but cooking carbohydrates involves other chemical processes, and heaven forbid that we know about fats and cooking chemistry.

The "Rule of Thumb" is useful as a rough guide to what to expect.

You will find, if you search, that the adjustments for cooking at altitude generally start with the boiling temperature of water vs altitude, and then veer off into other empirical observations of what works, and they avoid frightening the cook with any chemistry or science beyond the boiling of water.

There are a few exceptions to the last sentence, but very few.
• This law is on shaky grounds. Have you dug into the reasoning behind it? Or are you merely reposting what you read, without giving the source. Don s quote
Message 16 of 19 , Jun 1, 2011
This "law" is on shaky grounds. Have you dug into the reasoning behind it? Or are you merely reposting what you read, without giving the source.

Don's quote came from backpackinglight - their FAQ about canister stoves written by a staff member with a science background (Ph.D. in Ecological Physiology and Biochemistry from the University of Arizona).  The FAQ does not give the chemistry behind the statement.  I assume it is based on field experience.

I don't like backpackinglight philosophically, but I've found they are pretty reliable on science-related issues (when published by staff), at least within the realm of practicality

http://www.backpackinglight.com/cgi-bin/backpackinglight/canister_stove_faq.html

The FAQ author's bio is here - it doesn't make him right, but suggests you can probably rely on him absent contrary evidence.

http://www.backpackinglight.com/cgi-bin/backpackinglight/will_rietveld_bio.html

1616 Castro Street
San Francisco, CA  94114-3707
415-648-9279

On Wed, Jun 1, 2011 at 4:43 PM, JamesB wrote:

--- In johnmuirtrail@yahoogroups.com, Don Amundson <amrowinc@...> wrote:
>
>
>

> But enough of the silly mental musings.
> This blatantly stolen quip comes from a study on the subject and may shed light on your question.
>
> How Does Altitude Affect Cooking Time and Fuel Consumption?
> As you ascend in elevation, atmospheric pressure decreases and water
> boils at a lower temperature. For every 18 ï¿½F drop in the boiling point
> of water, it doubles the time to cook food. For example, the boiling
> point of water drops from 212 ï¿½F at sea level to 194 ï¿½F at 10,000 feet.
> It takes twice as long to cook raw food at 10,000 feet than it does at
> sea level.

This "law" is on shaky grounds. Have you dug into the reasoning behind it? Or are you merely reposting what you read, without giving the source.

http://www.rod.beavon.clara.net/Q10.htm
------------------------------- Quote ----------------------
"Q10 â€" rubber-stamp â€˜thinkingâ€™.

â€˜Reaction rates double for every 10C rise in temperatureâ€™ â€" I expect that youâ€™ve heard this statement. It is, for some reason, very popular with those studying biology; it is there that you find Q10, the ratio of reaction rate at temperature T to that at T + 10. The doubling is usually offered as a fact of chemical (or biochemical) life; such a pity, then, that it isnâ€™t true.

As originally promulgated in university texts it was â€˜Reaction rates roughly double or tripleâ€¦â€™; but in the (ever-increasing) sanitising found in A level texts a number of fairly important words were jettisoned. Like â€˜roughlyâ€™, â€˜double or tripleâ€™. (Yes, guilty; if youâ€™ve read my Nelson texts there are numerous omissions there, and no, I donâ€™t like that.) A number of other important caveats disappeared too, so letâ€™s examine the ideas further."
---------------- End Quote ---------------------------

He then goes into details of the Arrhenius equation from which one can attempt to derive the conditions under which a 10 degree (Centigrade) temperature change will double the reaction rate..

Note that the original intent of the academic quote was to give a "Rule of Thumb" ( "roughly", "double or tripple the rate" ) which is requoted here as a "RULE OF ABSOLUTES". Just like one would expect of someone who never read the original, nor sensed the meaning of the original text.

http://antoine.frostburg.edu/chem/senese/101/kinetics/faq/temperature-and-reaction-rate.shtml

Does a 10Â°C temperature rise double reaction rates? [10C=18F]

This web page provides the basic equations and a calculator for reaction rate doubling using the standard Arrhenius Reaction Rate relationship.

Something called the "Activation Energy" for the substance reacting must have a specific value for the "Doubling every 10C (18F)" to occur.

Does your food have these requirements met? Have you ever inquired about the activation energy involved in cooking? But you quote a result based upon a specific activation energy.

Well, no. Did you know that cooking proteins often involves denaturing, but cooking carbohydrates involves other chemical processes, and heaven forbid that we know about fats and cooking chemistry.

The "Rule of Thumb" is useful as a rough guide to what to expect.

You will find, if you search, that the adjustments for cooking at altitude generally start with the boiling temperature of water vs altitude, and then veer off into other empirical observations of what works, and they avoid frightening the cook with any chemistry or science beyond the boiling of water.

There are a few exceptions to the last sentence, but very few.

• Though I usually refer all matters of law to my lawyer I thought in this case I would answer your inquiry directly. Question #1: No Question #2: Yes To:
Message 17 of 19 , Jun 1, 2011
Though I usually refer all matters of law to my lawyer I thought in this case I would answer your inquiry directly.

Question #1:  No   Question #2:  Yes

To: johnmuirtrail@yahoogroups.com
From: jdbuch123@...

This "law" is on shaky grounds. Have you dug into the reasoning behind it? Or are you merely reposting what you read, without giving the source.

• ... Cooking and temperature can be deceptive. You can cook a turkey in, say, 6 hours at 350F. But turning up the oven 18F to 368F doesn t cook it in 3 hours.
Message 18 of 19 , Jun 2, 2011
>
> This "law" is on shaky grounds. Have you dug into the reasoning behind it?
> Or are you merely reposting what you read, without giving the source.
>
> Don's quote came from backpackinglight - their FAQ about canister stoves
> written by a staff member with a science background (Ph.D. in Ecological
> Physiology and Biochemistry from the University of Arizona). The FAQ does
> not give the chemistry behind the statement. I assume it is based on field
> experience.
>
> I don't like backpackinglight philosophically, but I've found they are
> least within the realm of practicality
>
> http://www.backpackinglight.com/cgi-bin/backpackinglight/canister_stove_faq.html
>
> The FAQ author's bio is here - it doesn't make him right, but suggests you
> can probably rely on him absent contrary evidence.
>
> http://www.backpackinglight.com/cgi-bin/backpackinglight/will_rietveld_bio.html
>
> 1616 Castro Street
> San Francisco, CA 94114-3707
> 415-648-9279
>
>

Cooking and temperature can be deceptive.

You can cook a turkey in, say, 6 hours at 350F. But turning up the oven 18F to 368F doesn't cook it in 3 hours.

You need to apply rules of thumb with some understanding of when they do and don't apply.

Pasta (carbohydrates) and meat (proteins and fat) cook by different chemistry and kinetics.

PhD in science .... hell, I thought everyone had one. I got one, where's yours?
• ... I cook my freeze dried chicken on the JMT in the time it takes to heat the water, plus a few minutes of soak time. The food is already cooked, so this
Message 19 of 19 , Jun 2, 2011
>
> You can cook a turkey in, say, 6 hours at 350F. But turning up the oven 18F to 368F doesn't cook it in 3 hours.
>

I "cook" my freeze dried chicken on the JMT in the time it takes to heat the water, plus a few minutes of soak time. The food is already cooked, so this debate is completely meaningless, unless you're up there cooking fresh marmot meat until tender.

as long as the food you're "cooking" can be consumed with just rehydration, the hot water is just a matter of taste. All you're doing at elevation is heating up water to a lower boil point, which actually works in your favor regarding fuel consumption. The colder water will cost you some fuel - in my testing with 58F and 35F water the Jetboil Sol needed about 20 seconds more time and 0.7 grams more fuel to boil 0.5L at 900 F elevation. It takes 5.5 grams to boil 0.5L of ice water, so a 110g canister will do about 10 liters.
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