“No vehicle is currently anywhere close to meeting these standards: According to data from the Energy Department, motorcycles come closest, at just shy of 45 miles per gallon, while cars average less than 25 miles per gallon. But the standards are fleet-wide, meaning the average for all of an automaker’s output needs to fall below the minimum. In practice, this means manufacturers must rely heavily on low- or zero-emission vehicles, like battery-powered electric vehicles or plug-in hybrids, to get on the right side of the average.
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The Senate version of the “big, beautiful bill” sets both of these dollar amounts at “$0.00,” effectively rendering it moot: Automakers making cars that don’t adhere to CAFE standards will still technically be in violation of the law, but they would face no reprisal.”