Just as a point of clarification, butane and propane are both very similar gases derived from petroleum refining.
Butane has a little more heat in it because it has more bonds to break when burning. (Butane is C4H10, whereas propane is C3H8).
Different gas fuels intended for different uses can be more of one and less of the other, or vis-a-vis. Sometimes there blended in order to accomodate low ambient temperatures in the winter to avoid solidification.
Butane is used more in small, non-reusable or refillable appliances to have more energy in less space, e.g. lighters of various types and small stove/lantern canisters.
Propane is used more for applications where bulk transfer and storage volume are not as much an issue, i.e., home heating, RV heating/refrigeration/cooking, etc.
I much prefer propane cooking and heating aboard a boat for ease of operation. One just has to take all the precautions, have quality equipment and safety devices, and the knowledge and perseverance to make it work.
Joe.
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