On the Trailspace forum I was asked a question “Had your tests been performed with a GCS pot, I think you would have seen very different results. The GCS’s heat exchanger is fully exposed and therefore far more vulnerable to wind.”
So on the weekend I ran some wind tests on the Jet Boil Group Cooking System (GCS).
These test were done slightly different than the PCS tests as I ran the remote canister in upright configuration, I decided to do this to try and get better consistency in the tests, to do this I put a adjustable valve on the canister and ran the JetBoil stove until the flame at a high level and was stable I then only used the valve on the canister to turn the stove on and off. My STD 0.5 liters of water were used. The wind speed measured was around 12-15 kph.
Test 1, GCS pot and remote canister JetBoil stove, no wind and no windscreen/
Fuel used in grams per 80ºC = 5.0g
Test 2, wind with windscreen, stove was lit then windscreen placed around stove, then fan turned on.
Fuel used in grams per 80ºC = 5.5g
Test 3, wind, no windscreen, During this test it was obvious that it this system is greatly effected by wind and to raise the water to 95ºC was going to take some considerable time and fuel, I stopped the tests at the same time as the no wind test and as the heating rate is usually linear I extrapolate the results.
Fuel used in grams per 80ºC = 25.4g
Heating rate graph, pink line no wind/ no windscreen, blue line, wind/windscreen, yellow line wind/no windscreen
Discussion of results.
As can be seen from the fuel used in the wind/no windscreen test the GCS stove efficiency is affected quite a lot by wind but the use of a windscreen does improve the efficiency and possibly if the windscreen is setup properly wind may have no effect, the difference between the results of the no wind and wind/windscreen tests is very small this difference could be considered in normal testing error.
Unlike the PCS stove the GCS stove system efficiency is greatly affected by wind but the use of a good fitting windscreen can greatly improve efficiency to the point that the wind may have little or no effect.