Rise of the Itty-Bitty Car: How Green Are the New Uber Compacts?

The media blitz for the New York International Auto Show doesn’t kick into high gear until tomorrow, but automakers are itching to get their new toys out ahead of time. Among the concept cars slated to debut at the show this week is a Toyota Scion “micro-subcompact” that the company has said represents “a new segment for the brand aimed toward the growing urbanization trend.” Wondering what that looks like? Think Smart Fortwo, Tata Nano — or Toyota iQ (s TM), the model now sold in Europe and Japan that may get a Scion badge for the U.S. market and is rumored to be the concept Scion plans to unveil tomorrow.

While these models seem downright beefy compared with General Motors (s GM) and Segway’s new PUMA concept, they’re worlds away from the 16 mpg Hummers of yesteryear. But they also run on gasoline. So does the new breed of itty bitty cars represent a way to prolong our reliance on fossil fuels and distract from work on cleaner technologies — or do their reduced material needs and improved fuel economy make subcompacts shining examples of green transport?

Fuel economy gains aren’t as big as you might expect for these slimmed down vehicles. The most recent U.S. EPA fuel economy ratings give the 2009 Fortwo coupe a combined 36 mpg (33 mpg city, 41 mpg highway). For comparison, the 2009 Toyota Prius gets 46 mpg (48 city, 45 highway) and the Honda Civic comes in at 29 mpg (25 city, 36 highway). According to the EPA, this translates to about a one-ton difference in annual carbon dioxide emissions, with the Fortwo emitting 1.1 tons more than the Prius and 1.2 tons less than the Civic.

There’s potential for much better mileage with these models — Toyota’s iQ has a whopping 54.1 mpg rating under Japan’s system, although it likely won’t test as high on the EPA scale.


It seems the greater potential, in terms of advancing the auto industry toward cleaner technology, lies in what these models might spawn. Based on Daimler (s DAI), Tata Motors (s TTM) and Toyota’s gameplans for their smallest models, the latest subcompacts could pave the road to a much greener generation of vehicles: namely, electric versions of the Fortwo (slated for a U.S. pilot rollout in 2010), Nano (Tata’s entry in this year’s X Prize competition) and iQ (pictured; displayed in concept form as the “FT-EV” at the Detroit Auto Show in January and appearing again at this week’s New York Auto Show). Here’s hoping for progress on shrinking the battery packs — these cars will be awfully cozy with a hefty pack in the back seat.

Photo courtesy New York International Auto Show; MPG graphic courtesy fueleconomy.gov