Peak oil

Peak oil is the theorized point in time when the maximum rate of global oil production will occur, after which oil production will begin an irreversible decline. The primary concern of peak oil is that global transportation heavily relies upon the use of gasoline and diesel fuel. Switching transportation to electric vehicles, biofuels, or more fuel-efficient forms of travel (trains, waterways) may help reduce oil demand.

Peak oil is very closely related to the concept of oil depletion; while global petroleum reserves are finite, the limiting factor is not whether the oil exists but whether it can be extracted economically at a given price. Historically, it was theorized that a secular decline in oil production would be caused by eventual depletion of known reserves, though more recently a new competing theory has emerged, that reductions in oil demand may reduce the price of oil relative to the cost of extraction, as might be induced to reduce carbon emissions. Or, demand may be reduced from demand destruction triggered by persistently high oil prices.

Numerous predictions of the timing of peak oil have been made over the past century before being falsified by subsequent growth in the rate of petroleum extraction. M. King Hubbert is often credited with introducing the notion in a 1956 paper which presented a formal theory and predicted U.S. extraction to peak between 1965 and 1971. Hubbert's original predictions for world peak oil production proved premature and, as of 2023, forecasts of the year of peak oil range from 2025 to 2040. These predictions are dependent on future economic trends, technological developments, and efforts by societies and governments to mitigate climate change.