Fossil fuels (coal, oil and gas) have provided our modern civilisation with abundant, cheap, high-density energy. However, their massive use released considerable amounts of carbon dioxide (CO2) in the atmosphere, changing the global climate. Indeed, each 1000 billion tonnes of CO2 emitted causes a global surface temperature change assessed to be around +0.45°C. About 2400 billion tonnes of CO2 have already been emitted since 1850.
To limit global warming to a given temperature, cumulative emissions should be kept within a carbon budget. This implies that annual emissions should decrease fast and ultimately reach net-zero, i.e., that they become fully balanced by deliberate removals from the atmosphere in addition to capture by natural carbon sinks. Stopping burning fossil fuels is therefore crucial.
Global fossil fuel reserves are at a level comfortably sufficient to meet demand at least until 2050, thus it is not possible to simply wait for their depletion to stay within the remaining carbon budget. A significant part of the world’s fossil fuel reserves must be left in the ground. However, abundant reserves do not necessarily translate into abundant supply, as shown by the ongoing energy crisis. Indeed, production capacities are fixed in the near term by past upstream investments and discoveries, so they can only weakly respond to demand changes. In particular, supply tensions can occur if upstream investment is reduced too quickly.
Demand itself depends on many parameters and, in the short term, it has notably been affected by the Covid-19 pandemics and the ongoing energy crisis. The speed and scale of both the economic recovery and the green transition are hard to foresee. For the first time this year, all the scenarios from BP and the IEA foresee an eventual decline in global oil demand by the mid-2030s at the latest. At the same time, the latest forecast from the IEA expects a new all-time high for coal demand in the next two years, while, until very recently, most scenarios agreed that it would never recover to its 2013 peak level.
The future evolution of fossil fuel demand will mainly depend on our collective ability to bridge both ambition and implementation gaps to make climate pledges appropriately ambitious and turn them into actions. It will require the implementation of strong policies to massively deploy low-carbon energy sources and technologies to fill the gap, as well as reducing the all-fuel energy demand through energy efficiency measures and behavioural changes.