Automaker lobbyists continue to push back against the stricter fuel-economy and emissions standards scheduled to take effect in the U.S. over the next decade.
Many of their arguments center on costs—not only to the carmakers themselves, but also to car buyers.
Regulators and automakers together acknowledge that complying with tougher standards will add to the cost of making vehicles. Car-company lobbyists claim those costs will be passed onto consumers in the form of higher purchase prices.
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But increasingly strict fuel-economy requirements have not, in fact, adversely impacted car prices over the last 20 years, according to a new report (pdf) from Consumers Union, the parent of Consumer Reports magazine.
Researchers looked at new- and user-car prices over the last 20 years, and found that they have remained largely stable even as fuel economy has improved.
The most affordable vehicle among the top 30 sold in 2015 cost the same (in real terms) as the most affordable top-30 vehicle in 2005, the report found.
1997 Honda Civic coupe
The situation was somewhat different for high-end models, as the price of the most expensive vehicle in the top 30 increased by 40 percent in the same period.
Across all income groups, spending on gasoline has decreased since 2005, according to the report, due in part to lower gas prices over the past few years.
Adjusting for inflation, gas prices have fallen 12 percent since 2005, while fuel economy improved by 25 percent, the report said.
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Based solely on fuel-efficiency gains, the average household saved $523 on fuel annually in 2015 compared to 2005.
Improved fuel economy actually has an outsize impact on low-income household, Consumers Union noted.
Low-income households spend more money putting gasoline into vehicles than on buying them, making them more sensitive to fuel costs.
2017 Honda Civic
The group noted that another recent study concluded savings in fuel costs due to stricter fuel-economy standards made up 4.3 percent of annual income for the lowest-income quintile, as well as 0.9 percent for the highest-income quintile.
An earlier Consumers Union study also found that 2025 fuel-economy standards could save drivers $3,200 and $4,800 per truck.
Those figures were based on today's low gas prices, so savings would increase if gas prices went up.
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Automaker concerns over the cost of compliance with fuel-economy standards also contradict the findings of a Technical Assessment Report released by the Environmental Protection Agency last summer.
The report, which charted the progress of automakers in meeting fuel-economy standards, found that 2025 standards could largely be achieved with currently available technologies and continued improvements to the efficiency of internal-combustion engines.
It said large numbers of plug-in electric cars would be unnecessary, meaning automakers would not have to build and sell tens or hundreds of thousands of costlier plug-in vehicles to cut the fuel consumption of their lineups enough to meet 2025 CAFE goals.