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EPA Issues Automotive Trends Report, Noting Record Improvements in CO2 Emissions and Fuel Economy

To close out 2023, the US Environmental Protection Agency issued its annual Automotive Trends Report, which provides the public with information about vehicle greenhouse gas (GHG) emissions, fuel economy, technology data and innovation, and auto manufacturers’ performance in meeting the EPA’s GHG emissions standards. EPA has been collecting this information since 1975.

According to EPA, new vehicle CO2 emissions and fuel economy had the biggest annual improvement of the last nine years, reaching record low CO2 emissions and record high fuel economy. In model year 2022, the average real-world CO2 emission rate for all new vehicles fell by 10 g/mi to 337 g/mi, the lowest ever measured. Real-world fuel economy increased by 0.6 mpg to a record high of 26.0 mpg. EPA states that this is the largest single year improvement in CO2 emission rates and fuel economy in nine years. Since model year 2004, CO2 emissions have decreased 27%, or 123 g/mi, and fuel economy has increased 35%, or 6.7 mpg. Over that time, EPA notes that CO2 emissions have improved in 15 of 18 years.

The four largest vehicle types are at record low CO2 emissions; however, EPA states that long-term market shifts away from cars and towards sport utility vehicles have offset some of the fleetwide benefits. In this report, vehicles are categorized into five vehicle types: sedan/wagon, car SUV, truck SUV, pickup truck, and minivan/van. In model year 2022, four of the five vehicle types had their lowest CO2 emissions and highest fuel economy ever. Car SUVs decreased CO2 emissions by 27 g/mi, pickups decreased by 18 g/mi, sedan/wagons decreased by 11 g/mi and truck SUVs decreased by 4 g/mi. Minivan/vans, which accounted for less than 3% of new vehicle production in model year 2022, were the only vehicle type that had higher CO2 emissions in 2022 compared to 2021, increasing by 17 g/mi.

In model year 2022, 37% of all new vehicles were cars and 63% of all new vehicles were trucks under EPA’s light-duty GHG regulations. This is the highest percentage of trucks since at least 1975, and is projected to increase further in model year 2023. Further, hybrid vehicles reached a new high of 10% of all production. The combined category of electric vehicles (EVs), plug-in hybrid vehicles (PHEVs), and fuel cell electric vehicles (FCVs) increased from 4% of production in model year 2021 to 7% of production in model year 2022 and are projected to reach 12% of production in model year 2023. EPA expects that this trend will likely continue as EV production is expected to grow across the industry in coming years.

EPA also reported, as readers might expect, that manufacturers continue to use a wide array of advanced technologies. Engine technologies such as turbocharged engines (Turbo) and gasoline direct injection (GDI) allow for more efficient engine design and operation. A growing number of engines can use GDI or port fuel injection (GDPI) depending on conditions. Cylinder deactivation (CD) allows for use of only a portion of the engine when less power is needed, while stop/start systems can turn off the engine entirely at idle to save fuel. Hybrid vehicles use a larger battery to recapture braking energy and provide power when necessary, allowing for a smaller, more efficiently operated engine. The hybrid category includes “strong” hybrid systems that can temporarily power the vehicle without engaging the engine and smaller “mild” hybrid systems that cannot propel the vehicle on their own. Transmissions that have more gear ratios, or speeds, allow the engine to more frequently operate near peak efficiency.

Overall, according to EPA, through the model year 2022 reporting period, all large manufacturers are in compliance with the light duty GHG program requirements. EPA’s GHG program is an averaging, banking, and trading (ABT) program, which means that the standards may be met on a fleet average basis, manufacturers may earn and bank credits to use later, and manufacturers may trade credits with other manufacturers. You can review the entire report here or the executive summary here.