Fuel economy in the United States

In 2019, slightly more than 16 million light-duty vehicles (LDVs) were sold in the United States. With an average fuel consumption of 8.6 litres of gasoline equivalent (Lge/ 100 km) for new LDVs in 2019, the United States is 20% above the global average. While fuel consumption of LDVs decreased on average by 2.1% per year from 2005 to 2017, improvements have slipped backwards with fuel consumption increasing by 0.6% between 2018 and 2019.

The lapse in fuel consumption reductions is reflected in slowing improvements in fuel economy across LDV segments. Despite significant improvments in all segments since 2005, improvement rates have since slowed, and in the case of large SUVs and city cars, fuel consumption has increased on average by 1.8% and 0.5% per year, repsectively since 2017. The market for SUVs/pick-up trucks expanded to a 65% sales share in 2019, though growth has primarily occurred within the small SUV/pick-up segment with sales shares increasing by 7% since 2017. In spite of increasing shares of SUVs/pick-ups, the average weight of LDVs has not increased since 2005 and was 1 768 kg in 2019, which is almost 20% above the global average.

Gasoline LDVs were 88% of LDV sales in 2019 in the United States. Sales shares of flexfuel LDVs continue to decline in the United States, from a high of 20% in 2012 to less than 6% in 2019. Similarly, the market for hybrid vehicles has declined since 2013, reaching a sales share of 2.4% in 2019. In contrast, sales shares of electric and plug-in LDVs are growing. In particular, battery electric vehicles were 0.4% of LDV sales in 2015 and 1.5% of sales in 2019.

The United States introduced fuel economy regulations as early as 1975 with the Corporate Average Fuel Economy (CAFE) standards. The standards in a given model year define the levels that manufacturers' fleets are required to meet in that model year (MY), with specific levels depending on the characteristics and mix of vehicles produced by each manufacturer. In 2020, the Safer Affordable Fuel-Efficient (SAFE) Vehicles Rule set fuel economy standards that were significantly less stringent than previous standards established in 2012. The SAFE rule introduced an annual fuel economy improvement rate of 1.5% for model years 2021-2026, while previous standards required a 4.7% yearly improvement for 2017-2025. SAFE also phased out the GHG credit multiplier for electric vehicles in 2022 and extended the multiplier for natural gas vehicles to 2026.

In January 2021, the new US administration issued an executive order directing the EPA to reconsider the SAFE programme, and in August 2021 a revision was proposed to establish more stringent standards starting in 2023. Compared with SAFE, the proposed standards represent a 10% greater improvement for model year 2023 and a 5% improvement in the years following. The revision proposes removing the natural gas multiplier and extending the credit multiplier for electric vehicles to model year 2025. Final rules will be established in December 2021. 

The United States Environmental Protection Agency is responsible for providing the fuel economy data that is used to label all new cars and light trucks, and periodically updates its methodology to account for changes in vehicle technologies, driving behaviour and/or conditions. The label provides information on vehicle fuel economy and CO2 grams per mile. In 2021, the US administration announced a target for electric vehicles to make up 50% of new passenger car and light truck sales by 2030. Battery electric and plug-in hybrid vehicles purchased in or after 2010 are eligible for a federal income tax credit of up to USD 7 500.