Thanks to improved designs, lightweight materials, turbochargers, direct injection and even better gearbox design, cars on dealers’ lots today get far better gas mileage than cars made in the past few years. 

But while buyers are keen to buy the latest generation of green, high-mpg cars, some within the automotive industry are warning that demand of fuel-efficient cars will outstrip supply this summer. 

According to Automotive News (subscription required), demand for some high-mpg cars is already so high that four automakers are dramatically-increasing production. Interestingly, all are mid-size cars, not compacts or superminis. 

Volkswagen’s Chattanooga plant, where its 2012 Passat is built, is planning a third shift to allow it to boost annual production from 150,000 cars to 180,000 cars. Volkswagen hasn't disclosed what proportion of the increased production will be reserved for its diesel-powered 2.0-liter TDI passat, which is capable of an impressive 35 mpg combined.  Beyond initial expansion however, the German automaker has already examined the costs to increase U.S. production to 250,000 Passats annually. 

In West Point, Georgia, the Kia factory where the 2012 Optima is built is now running overtime, in part to increase the automakers’ shockingly low vehicle stock.  At the start of June, the Korean automaker only had enough cars to last 25 days of sales. 

 Its most fuel-efficient variant, the 2012 Optima Hybrid, is rated at 37 mpg combined.

2013 Hyundai Sonata

2013 Hyundai Sonata

The story is the same in Montgomery, Alabama, where Kia’s parent company Hyundai builds the 2013 Sonata. With the non-hybrid Sonata managing 28 mpg combined from its 2.4-liter engine, it is currently working overtime on weekdays and Saturdays until a third shift is officially started in September. At the start of June, it reported just 22 days of stock. 

Toyota too, is experiencing a surge in demand for its 2012 Camry. With sales up 44 percent through May, the redesigned, 28-mpg combined car has proven popular with buyers. In response, Toyota has scheduled daily and Saturday overtime at many of its U.S. plants. 

But those looking to buy a fuel efficient car this summer won’t just be hit with a wait for a car: they may have to pay more for it too. 

Dealer - Sale

Dealer - Sale

As the average time a 2012 Toyota Prius Plug-in Hybrid sat on dealer lots earlier this year, cars which get good gas mileage are in so much demand that they don’t spend very long sitting on dealer lots. 

As a consequence, dealers aren’t offering many incentives or price-drops on 2013 model cars, but are offering huge discounts and special deals to anyone willing to walk out with lower-MPG cars from last year.

High demand and low supply also means that some dealers may be tempted to put a markup -- or price-gouge -- popular high-mpg models. 

Our advice?

  • If you’re looking for a high-mpg car this summer, especially a mid-size one, make sure you research the cars you’re looking to buy thoroughly before you head to a dealer. 
  • Be sure to check our buying guide section -- which lists MSRP for each car -- to make sure your local dealer hasn’t overpriced the car. 
  • Be prepared to wait a few extra months, when supplies are larger and dealers will be more willing to give you a discount. 

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