At a refinery, the crude oil from underground is separated into natural gas, gasoline, kerosene, and various oils.

Producers grew skeptical of markets and saw an array of potential plots against them, from consumer taxes on gasoline to efforts to replace oil with natural gas and renewable energy sources.

Advocates like the former oil tycoon T. Boone Pickens have also long sought to promote it as a substitute for coal in electricity generation or gasoline in a new generation of natural gas cars.