
The challenges and limitations mentioned regarding the NHTSA's ability to consider electric vehicles (EVs) in setting new mileage standards are largely related to the outdated regulations and the legal framework under which the agency operates. The current regulations and legal requirements do not adequately account for the rapid advancements in vehicle technology, specifically the rise of EVs.
Firstly, the NHTSA is bound by statutory limitations that prevent it from explicitly considering EVs in setting mileage standards. This means that the agency cannot directly incorporate the increasing market share of EVs and their unique characteristics into the development of new fuel-economy standards.
Secondly, the existing regulations were designed primarily for internal combustion engine vehicles, with the aim of promoting energy conservation and reducing dependence on foreign oil. As a result, these regulations may not be entirely suitable or effective for addressing the environmental and energy-related challenges posed by the growing EV market.
Furthermore, the NHTSA's authority to issue vehicle safety standards and its role in regulating fuel economy standards may create conflicts or discrepancies between the agency's safety and environmental objectives. For instance, more stringent fuel-economy standards could potentially lead to compromises in vehicle safety, or vice versa.
Lastly, the industry's transition to electrification may render the traditional mileage standards, which were designed for gasoline-powered vehicles, less relevant over time. As EVs do not have tailpipes or rely on combustion, the conventional methods of measuring fuel efficiency and emissions may not be applicable or useful for evaluating the environmental impact of these vehicles.
In summary, the challenges and limitations facing the NHTSA in considering EVs in mileage standards stem from the outdated regulatory framework, statutory limitations, and the unique characteristics of EVs that make them difficult to incorporate into existing fuel-economy standards.

The new mileage standard for 2031 requires new vehicles sold in the U.S. to average about 38 miles per gallon (mpg) in real-world driving, which is an increase from the current average of about 29 mpg. This new standard is part of the federal rules unveiled by the Biden administration to improve fuel economy and reduce greenhouse gas emissions. The final rule will increase fuel economy by 2% per year for model years 2027 to 2031 for passenger cars, while SUVs and other light trucks will increase by 2% per year for model years 2029 to 2031.

The final fuel economy figures released by the Biden administration differ from the initial proposal in that they are less stringent. Under the final rule, new vehicles sold in the U.S. will have to average about 38 miles per gallon of gasoline in 2031 in real-world driving, up from about 29 mpg this year. The final figures are below the proposal released last year.
The administration gave two main reasons for this adjustment. First, they said that the less stringent requirements will allow the auto industry flexibility to focus on electric vehicles. Second, they argued that higher gas-mileage requirements would have imposed significant costs on consumers without sufficient fuel savings to offset them6.