California became the first state to approve standards for tire efficiency, aiming to ensure replacement tires match original equipment fuel efficiency. The California Energy Commission unanimously approved a rule with a labeling system using a 'leaf' rating to help consumers identify efficient tires. The regulation could save drivers $1 billion annually and reduce CO2 emissions by 2 million tons yearly, equivalent to taking 400,000 cars off the road.

The rule phases in starting 2029, with stricter standards by 2033, addressing manufacturer concerns. Exemptions include snow and competition tires, though all-weather tires will be tracked for future regulation. Critics like the Consumer Federation of America argued the timeline and exemptions fall short, while industry groups are split—Michelin supports the goals, while SEMA worries about costs burdening working families.

Manufacturers can choose whether to display the leaf label, with a four-leaf tire denoting highest efficiency. The state estimates more efficient tires cost $6 to $26 more per set but save $85 to $153 over their lifetime. Supporters say the rule could boost EV range and ease grid demand, with other states likely to follow.