Liquefied petroleum gas Commercially available LPG is currently derived mainly from fossil fuels. Burning LPG releases carbon dioxide, a greenhouse gas. The reaction also produces some carbon monoxide. LPG does, however, release less per unit of energy than does coal or oil. It emits 81% of the per kWh produced by oil, 70% of that of coal, and less than 50% of that emitted by coal-generated electricity distributed via the grid. Being a mix of propane and butane, LPG emits less carbon per joule than butane but more carbon per joule than propane. LPG burns more cleanly than higher molecular weight hydrocarbons because
Gas leak and carbon monoxide present in natural gas. The expression "canary in a coal mine" derives from the historical practice of using a canary as an animal sentinel to detect toxic naturally occurring coal gas. Methane, the primary constituent of natural gas, is up to 120 times as potent a greenhouse gas as carbon dioxide. Thus, the release of unburned natural gas produces much stronger effects than the carbon dioxide that would have been released if the gas had been burned as intended. In the United States, most state and federal agencies have adopted the Gas Piping and Technology Committee (GPTC)