While economic and foreign policy issues have rightly dominated this year's presidential contest, one area that deserves more scrutiny is where the candidates stand on a key energy security issue: vehicle fuel efficiency.

In 2007, I joined Republican Sen. Olympia Snowe in authoring the Ten-in-Ten Fuel Economy Act, which will increase fleetwide fuel economy to 54.5 miles per gallon by 2025.

This landmark bill was signed by President George W. Bush. To date, this bill is the most significant federal law enacted to reduce carbon emissions, reduce our dependence on foreign oil and slow the warming of the planet.

What does the law do?

  • It requires fuel economy for cars, trucks and SUVs to increase at the maximum feasible rate between 2011 and 2030.
     
  • It created first-of-their-kind efficiency standards for delivery trucks and tractor trailers.

As a result, cars are now more fuel efficient, and the corporate average fuel-economy (CAFE) standards are based on technological feasibility and good science. This is progress.

Unfortunately, Gov. Mitt Romney opposes these increased fuel standards.

In fact, the Romney campaign contends these standards are "extreme," that they "will limit choices for American families," and that better fuel efficiency will cost consumers more money.

Those claims are wrong.

First, the 2007 statute requires that fuel economy standards increase at a cost-effective, technically feasible and safe rate, based on thorough scientific reviews conducted by the federal government and the National Academy of Sciences.

Second, the Ten-in-Ten Fuel Economy Act modified CAFE standards so they are based on the size of the vehicle -- so small cars are compared to small cars and SUVs are compared to SUVs. As a result, automakers are rewarded for making their products more efficient by adding fuel-efficient technology, like turbocharged, direct-injection engines.

Automakers receive no benefit from downsizing their fleet, so there is no basis to assert these standards limit consumer choice.

Third, the Obama administration united three separate regulators -- EPA, the state of California and the Department of Transportation -- behind a single regulatory regime, thereby reducing the burden of regulation on American business.

After a lengthy negotiation, 13 major automakers that sell more than 90 percent of all vehicles -- together with autoworkers, and environmental and safety groups -- endorsed a single, coherent regulatory regime that provided clear rules for the next 13 years. These rules reward innovation and provide the automobile industry with flexibility to increase average fuel economy using technology of its own choosing.

For motorists, the economic benefits of better fuel efficiency will be substantial. Consumers who drive their 2025-model-year vehicle for the length of its operation will save, on average, about $4,400, according to a comprehensive federal analysis.

Consumers who purchase vehicles in 2025 will save enough on fuel to cover the higher vehicle cost in less than three years, a savings that will continue to grow as long as the consumer owns the vehicle.

In other words, fuel savings will more than offset any premium paid for the vehicle. And if history is a guide, the auto industry will invent new, more cost effective ways to improve vehicle efficiency while it deploys existing hybrid technologies to dramatically lower cost.

For the general public and for our country, the environmental benefits will be meaningful. The increased standards will:

  • Reduce oil consumption by 12 billion barrels over the life of the program.
     
  • Reduce oil consumption by more than 2 million barrels a day by 2025 -- as much as half of the oil we currently import from OPEC daily.
     
  • Cut greenhouse gas emissions from cars and light trucks in half by 2025.

The evidence is unassailable: The planet is warming.

The inability of Congress to address climate change is a great disappointment. I hope that will change.

In the meantime, improved fuel efficiency -- developed in a bipartisan manner with input from science and industry -- is a practical approach to lowering oil consumption.

It is imperative for the next president to embrace this progress and continue improving the fuel efficiency of the American fleet.