Introduction — The expression ‘peak oil’ refers to the point at which oil production or consumption reaches its highest level before stabilising and then, potentially, declining. It therefore covers two different phenomena: peak supply, linked to resources and investment, and peak demand, influenced by uses, prices and alternatives. Confusing them can lead to mistaken conclusions about markets and energy security.
Key facts
- Peak production: the maximum output reached by a field, a country or global supply.
- Peak demand: the maximum level of oil consumption, followed by a sustained decline or a plateau.
- Scale: a field, a country, a product or the global market can reach its peak at different times.
- Forecasts: they depend on prices, policies, technologies and consumer choices.
What does ‘peak oil’ mean?
A peak is a maximum level observed or anticipated over a given period. In energy debates, the expression has mainly been used to describe the peak of global oil production. It also describes the point at which total oil demand could stop growing. These two peaks do not necessarily occur simultaneously.
The term must always be accompanied by a definition of its scope. Production from a field can peak several years after operations begin and then decline. A country's production may follow a different trajectory because of new discoveries, investment or political decisions. Globally, supply combines conventional resources, unconventional oils and liquids associated with gas. Demand encompasses different uses, such as road fuels, aviation, shipping and petrochemicals.
Peak production: geology and investment
In a reservoir, production depends on pressure, geology, equipment and recovery techniques. As hydrocarbons are extracted, output can decline naturally. Operators can slow this decline by drilling additional wells, injecting water or gas, maintaining pressure or improving facilities. A single field can therefore experience several periods of plateau production or recovery.
Globally, a possible production peak would not be determined solely by the quantity of oil underground. It would also depend on the pace at which new projects are discovered and brought into operation, investment in existing fields, costs, prices, logistical constraints and producers' decisions. Declining fields often need to be offset by new volumes simply to maintain total supply.
The International Energy Agency emphasises that a significant share of recent upstream investment goes towards offsetting decline in existing fields. Its analysis of nearly 15,000 oil and gas fields shows that decline rates vary considerably according to their size, location and technology. This explains why a fall in investment can affect supply even when geological resources remain abundant.
Peak demand: uses and substitution
Demand depends on economic activity and end uses. Road transport has long been a major driver of consumption, while petrochemical products, jet fuel and shipping follow their own trends. Electric vehicles, energy efficiency, biofuels, public transport and rail can reduce certain uses of oil. Conversely, growth in travel, aviation or plastics production can support demand.
In 2025, global oil demand increased by around 0.7%, or 0.65 million barrels per day. This growth was weaker than before the pandemic. Regional trajectories differ: some emerging economies are still increasing consumption, while several advanced economies are recording structural declines in road fuels.
The IEA's projections now place global demand on a trajectory of slower growth, a plateau or a slight decline by 2030, depending on the assumptions used. This is not a certain date. A projection changes if economic growth, policies, prices, infrastructure and technology adoption evolve. Scenarios describe conditional trajectories, rather than a single prediction.
Why do forecasts differ?
Institutions and companies do not use the same scenarios. Some forecasts assume rapid implementation of climate policies and low-carbon technologies; others extend current trends further or give greater weight to growth in emerging economies. Definitions also differ: some measures cover crude oil, while others include natural gas liquids, biofuels or liquid fuels made from other feedstocks.
Prices influence both sides of the market. High prices can encourage efficiency and substitution while making previously costly resources more profitable. Low prices can stimulate consumption in the short term but reduce investment in new projects. Geopolitical shocks or production decisions can also shift volumes without immediately changing underlying trends.
What are the implications for African producing countries?
Peak demand is a fiscal issue for states that depend on oil revenues. Slowing global demand does not mean that every country will immediately lose its market: production costs, crude quality, infrastructure, contracts and regional demand influence competitiveness. However, volatility makes revenues harder to forecast and increases the risk of financing permanent expenditure with temporary income.
New projects must be assessed on the basis of their full costs, timelines, emissions, infrastructure requirements and ability to generate local value. Countries can reduce their vulnerability by developing refining where economically appropriate, diversifying public revenues, establishing stabilisation mechanisms and investing in electricity, skills and productive activities.
Peak production presents another challenge: a fall in supply does not guarantee an orderly transition. If demand remains high and investment falls too quickly, prices can rise and supplies become less stable. Planning must therefore account for both the natural decline of fields and the gradual transformation of end uses.
Frequently asked questions
Has peak oil already been reached?
There is no universal answer without specifying whether the discussion concerns production or demand, crude oil or all liquids, and which region. Observed data can confirm a peak only retrospectively; projections remain conditional.
Does peak demand mean the end of oil?
No. A peak indicates a maximum, not an immediate disappearance. Oil may continue to be used for decades in sectors where alternatives are harder to deploy.
Does peak production necessarily cause a shortage?
Not necessarily. Inventories, available production capacity, substitution, demand and producing countries' decisions influence the situation. A production peak can be followed by a gradual decline or by changes offset by other sources.