[MtnClimber]

OOPs. One cubic foot of natural gas is about 1,000 BTU.

From https://www.eia.gov/energyexplained/units-and-calculators/

Btu content of common energy units (preliminary estimates for 20221

1 barrel (42 gallons) of crude oil produced in the United States = 5,684,000 Btu

1 gallon of finished motor gasoline (containing about 10% fuel ethanol by volume) = 120,214 Btu

1 gallon of diesel fuel or heating oil (with sulfur content less than 15 parts per million) = 137,381 Btu

1 gallon of heating oil (with sulfur content at 15 to 500 parts per million) = 138,500 Btu

1 barrel of residual fuel oil = 6,287,000 Btu

1 cubic foot of natural gas = 1,036 Btu

1 gallon of propane = 91,452 Btu

1 short ton (2,000 pounds) of coal (consumed by the electric power sector) = 18,820,000 Btu

1 kilowatthour of electricity = 3,412 Btu

[MtnClimber]

Coal is about $6.50 per mmBtu on the coal futures market, without delivery cost.