Net Zero: The Remaining Global Market Volume for Internal Combustion Engines in Light-Duty Vehicles under a 1.5 °C Carbon Budget Trajectory

To achieve the goals of the Paris Climate Agreement, decarbonization targets for the global automotive industry are required. We assess the quantity of light-duty vehicles (LDVs) with internal combustion engines (ICEs) that can be manufactured within the identified carbon budget and compare it with the current sales plans of the four largest automobile manufacturers—Volkswagen, General Motors, Toyota, and Hyundai/Kia—as representative of traditional car manufacturers. We first describe the quantification of a carbon budget for LDVs under the 1.5 °C target and a methodology for calculating the market shares that will allow different drive-train technologies to stay within it. The global LDV market for new sales and historic and future vehicle retirement rates are presented, together with assumptions for car usage (in passenger kilometres per year) and fuel efficiencies. We calculate the quantity of ICE LDVs that can be sold before the manufacture of ICEs must cease globally. We then compare this upper global limit with the current sales plans of car companies. The plans of the four manufacturers differ, but all considerably exceed the number of ICE vehicle sales required to meet the 1.5 °C target. This analysis does not forecast the development of the global LDV market, but assesses the gap between manufacturers’ intention and the requirement under a 1.5 °C pathway.