The history of energy is one of gradual substitutions from inefficient, dirtier, expensive options to cleaner, cheaper, higher-performing fuels. Mills and machines replaced manual labor, and more recently electricity replaced kerosene, which had replaced whale oil for lighting, and coal replaced wood for industry and heating buildings. But what about gases? A century ago, town gas was manufactured by burning coal, producing coke and a blend of methane and hydrogen but also toxic gases such as CO and other pollutants along the way. Later, large reserves of natural gas (primarily composed of methane) were found, which were both cheaper and cleaner, so we stopped manufacturing town gas. As a result of methane’s utility, abundance and affordability, it is used for just about every sector of society. Today that gas is used for heating, cooking, power generation, and as a feedstock to make materials such as chemicals and plastics.