Yesterday we reported on the delay getting range-extended versions of BMW's 2014 i3 electric car to the market, pending the confirmation and fitment of their EPA-approved window stickers.

That wait may not be much longer--and now we know the car's official EPA-rated mileage.

The 2014 BMW i3 REx is rated at 117 MPGe on electric power (29 kWh/100 miles), with a 72-mile all-electric range. On gasoline, once the range-extending engine kicks in, the REx gets combined mileage of 39 mpg.

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For comparison, the all-electric 2014 i3 is rated at 124 MPGe--the highest of any electric car on sale--with an 81-mile range.

The differences between the all-electric and range-extended cars in electric mode can be explained by the latter model's heavier weight--on account of the twin-cylinder gasoline engine sitting below its rear deck.

The window sticker was revealed by EV advocate, i3 buyer and restaurateur Tom Moloughney via the BMW i3 Facebook group.

It also gives the i3 REx a ten-from-ten score on tailpipe greenhouse gas emissions, and a five out of ten tailpipe smog rating. It lists an annual fuel cost of $650--based on 15,000 miles per year at $3.75 per gallon, and $0.12 per kilowatt-hour.

The EPA figures also make the i3 a more efficient car than one of its closest conceptual rivals, the range-extended Chevrolet Volt.

The Volt achieves 98 MPGe (35 kWh/100 miles) on electric power, and returns 37 mpg combined once running on its 1.4-liter range-extending engine.

Hundreds of 2014 BMW i3 REx cars are currently parked up at ports around the country, waiting on their EPA window stickers--also known as a "Monroney" document--before they can be legally delivered to customers.

As of yesterday, May 20, BMW said it foresaw receipt and application of the documents to the cars before the end of this week.


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