Estimate camping stove fuel needs.
Stove fuel is a thermodynamics problem with two big correction factors. Heating one litre of water from 10 C to boiling takes about 377 kJ, which is fixed physics. What varies is how much of the fuel's energy reaches the water: an integrated heat-exchanger system captures nearly 80 percent, a bare upright canister stove around 55 percent, and an alcohol burner only about 35 percent. Alcohol is doubly penalised because its energy density is roughly half that of butane. Wind is the other multiplier and it is severe — an exposed stove without a windscreen can burn 50 percent more fuel for the same boil.
Energy per litre
kJ = 4.186 x (100 - start temp C)
Fuel per litre
Grams = kJ per litre / (fuel kJ per g x stove efficiency) x wind factor
The fins bonded to the pot base capture heat that would otherwise escape around the sides, and the integrated windshield stops convective loss. That lifts efficiency from around 55 percent to nearly 80, which on a week-long trip can be the difference between two canisters and one.
Two reasons compound. Cold water starts further from boiling, so more energy is needed per litre. Separately, canister pressure falls as the gas chills, weakening the flame and lengthening boil times — which is why liquid fuel stoves are preferred for winter and alpine use.