Colorado Becomes First State in Mountain West to Adopt Second-Generation Clean Car Standard

October 20, 2023
Sharyn Stein, 202-905-5718,

(Denver, CO – Friday, October 20) – The Colorado Air Quality Control Commission voted unanimously today to adopt the Advanced Clean Car II (ACCII) standard – second-generation safeguards that will expand sales of new zero-emitting cars and passenger trucks in the state, slash climate and health-harming pollution, and save Coloradans billions of dollars on health care costs and fuel and maintenance for their vehicles.

“The Advanced Clean Car II standard will dramatically cut climate pollution and help clean up the air that Coloradans breathe,” said Larissa Koehler, Director of Vehicle Electrification and Senior Attorney for Environmental Defense Fund. “More zero-emitting vehicles in Colorado also means a more robust market for Colorado consumers, and that will mean even more savings for Coloradans who choose to buy a new zero-emitting car or truck. Today the Air Quality Control Commission took a key step to make the lives of all Coloradans better."

The ACCII standard adopted today will be implemented beginning in 2027 and run through 2032.  During that time, the standard will require increasing sales of new zero-emitting vehicles and will strengthen protections against harmful air pollutants from gas-powered vehicles. Under the new standard, 82% of new passenger vehicles sold in Colorado will be zero-emission in 2032.

The Colorado Air Quality Control Commission also voted to require a state agency to bring a proposal no later than July 31, 2029 for the Commission to consider extending the standard through 2035. EDF advocated for this feasible and important step, which would set a target for 100% sales of new zero-emission cars and passenger trucks and would help move Colorado closer to eliminating all traffic pollution in the state.

With today’s vote, Colorado joins eight other states that have now adopted the Advanced Clean Car II standard – California, Maryland, Vermont, Washington, Oregon, Massachusetts, Virginia, and New York – and becomes the first state in the Mountain West to adopt them. New Mexico and Connecticut are among the states now considering adopting the standard as well.

Colorado adopted the first generation Advanced Clean Car Standard in 2019.  

The Advanced Clean Car II standard will deliver enormous health and climate benefits. Colorado projects they will reduce 109 million tons of climate pollution and thousands of tons of smog-forming pollution through 2040. 

The standard will also expand consumer choice in the state, furthering current trends. Colorado saw a staggering 55% increase in electric vehicle sales between 2021 and 2022. By the end of 2025, automakers will have almost 200 electric vehicle models for sale across the country. That momentum will continue to drive down the price of zero-emission vehicles.

The Advanced Clean Car II standard will also help save consumers money in avoided fuel and maintenance costs. EDF conducted an analysis of the economic savings Coloradans could get from buying a currently available or soon anticipated electric vehicle. Our analysis found that consumers could save as much as $21,000 over the course of 10 years.

Colorado offers $5,000 in tax credits to support the purchase of a new zero-emission vehicle, which can be added to the federal tax credits of up to $7,500 under the Inflation Reduction Act. Under the Advanced Clean Car II standard, the state will also offer voluntary credits for manufacturers who take part in programs that benefit environmental justice communities, including rideshare programs, caps on retail costs for some vehicles, and sales of previously leased vehicles through a financial assistance program.

Today’s vote comes at a time when analyses from the state and EDF show Colorado remains off track from its 2025 and 2030 climate targets. While it makes important progress, in order to achieve the greenhouse gas emission reductions mandated by state statute, the Colorado Air Quality Control Commission needs to swiftly follow this action with the adoption of enforceable standards covering all major pollution sources.

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