Propane burns hotter than natural gas, but the difference is not significant. Both fuels burn at the same temperature of 3,560˚ Fahrenheit. However, propane generates more heat per unit than natural gas. One cubic foot of propane generates approximately 2,520 BTUs (British Thermal Units) of heat, while one cubic foot of natural gas generates only about 1,012 BTUs of heat. This means that you need more natural gas than propane to get the same amount of heat. For example, a 100,000 BTU natural gas furnace will burn approximately 97 cubic feet in one hour, while a propane furnace will burn only 40 cubic feet in the same amount of time. In summary, propane burns hotter than natural gas, but the difference is not significant, and both fuels are great options for grilling and heating.