March 17, 2013

Why do European cars have twice the fuel efficiency as in the US?

Dear Senator/Representative:

I use the Mini Cooper Clubman (manual transmission) as a typical example here, and because the Clubman is a larger model. Compare these fuel efficiency figures:

US: 35 mpg hwy, 27 cty, 30 comb.

UK: 50 mpg hwy, 34 cty, 43 comb. (CO₂ emissions 129 g/km, 152 g/mi)
(converted from Imperial to US gallons)

UK: 65 mpg hwy, 53 cty, 60 comb. (CO₂ emissions 103 g/km, 138 g/mi)
(converted from Imperial to US gallons)

These new super-efficient diesel engines (and apparently the regular gas engines, too) are burdened in the U.S. with obsolete particulate emissions rules that severely reduce their efficiency.

Whereas their efficiency ensures very low emissions anyway.

Please do all you can to allow the new-generation diesel engines that Europeans enjoy into the US, without forcing them (or even regular gas engines) to lose their incredible efficiency.

Imagine cutting the greenhouse gas emissions from most of our cars by half!

[comment:  CO₂ emissions are not regulated in either the U.S. or the E.U., and particulate emission limits are similar (and similarly specified as g/mi or g/km), so it is even stranger that high-efficiency diesel-powered cars, common in Europe, are not available in the U.S. Or that those few diesels that are available in the U.S. (e.g., from Volkswagen) get much less mileage than comparable models in Europe.]