For my West Coast Trail trip, I decided to use a stove that works with compressed isobutene/propane canisters instead of my usual MSR whisperlite stove that uses a white gas fuel bottle. The burner plus gas canister represents a significant size and weight savings over my MSR setup.
Prior to my trip, I wanted to understand how much fuel I would likely need so that I could buy the appropriately sized canister. Additionally, I wanted to determine which of my two cooking pots would be best given the particulars of the trip. I would only be cooking for myself, and I would only boil enough water for dehydrated meals (max 2 cups at a time). The Olicamp pot has a higher capacity than the SnowPeak pot (~34 fl oz vs 28 fl oz), but it is also more than twice the weight of the SnowPeak pot (190g vs 85g). The Olicamp pot has ‘heat exchanger’ fins around the bottom, while the SnowPeak does not.
Materials:
SnowPeak Hybrid Summit cookset, Qty 1
Olicamp XTS hard anodized aluminum pot, Qty 1
Extech Instruments EX330 DMM with thermocouple input, Qty 1
K type thermocouple (8” rigid metal probe), Qty 1
Ring stand with 3 prong adjustable clamp, Qty, 1
Digital watch, Qty 1
Soto Windmaster burner, Qty 1
Coleman Isobutane/propane fuel canister, 250g size, Qty 1
Ozerti digital scale, ZK14-S (5100g limit) , Qty 1
Aluminum foil, ~6” x 6”, two layers thick
Measuring cup, 1C capacity
Procedure
The starting weight of the fuel canister was measured using the digital scale and recorded, along with the empty weights of the pots (without lids).
The ambient air temperature was measured using the Extech DMM and K-type thermocouple and recorded. Two cups of tap water were added to the SnowPeak pot, and the mass of the pot + water was measured and recorded.
The Soto burner was fitted onto the gas canister and placed on a stable surface (patio paver). The ring stand and clamp were positioned relative to the stove so that the thermocouple could be held in the water without touching the sides or bottom of the pot under test. The thermocouple was inserted through the center of the aluminum foil square – the foil served as a replacement lid for both pots. The SnowPeak pot was placed on the burner and the thermocouple was positioned so that the tip of the probe was in the center of the pot, in about half the depth of the water. The aluminum foil was then fitted to the top of the pot. The starting temperature of the water was measured and recorded, and then the burner was ignited following the manufacturer’s instructions. Temperature data was recorded every 15 seconds until the water reached a temperature of 200°F. When the water reached the specified temperature, the burner was immediately turned off. The set up was taken apart, and the burner removed from the gas canister. The mass of the canister was measured and recorded again, allowing the amount of fuel used to be calculated.
This process was repeated for the Olicamp stove, with the exception that the amount of water added to the pot was determined by the mass instead of volume alone. This was to ensure that the two pots contained the same amount of water – the digital scale being much more accurate/repeatable than the measuring cup.
Results
The SnowPeak pot used 8 grams of fuel and took 3:49 to get the water to 200°F. The Olicamp pot used 4 grams of fuel and took 2:07 to get the water to 200°F.
Based on these results, I calculated the estimated fuel I would need for the duration of my trip. The calculations included:
· An efficiency adjustment based on the theoretical vs. actual fuel used in this experiment
· A greater delta in starting and ending water temperatures (i.e. I expected the starting water temp to be lower than what I used and would need to bring it to 212°F)
· Figuring on 6 boils instead of 5 (in case we had to be on the trail for a day longer than expected)
· A safety factor of 1.5
Even with all of these elements factored in, the amount of fuel required to use the SnowPeak pot for the trip was less than the smallest capacity canister that I could buy. This meant that the choice of pots could be made solely on their respective weights, and the SnowPeak was the clear choice.
[ATTACH=full]288377[/ATTACH]