A petrol tank cannot be used to contain butane or propane. A separate tank, like those used for domestic appliances, has to be fitted. This adds weight, and takes up space, usually in the boot or the back of a truck, less commonly on the roof of the cab. It is filled in the same way as domestic tanks are filled.
Propane has a higher calorific value than butane and when used in equipment to produce heat (as in a vehicle), uses less than butane for the same result.
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