Adding the small range-extending engine to the 2014 BMW i3 battery-electric minicar will increase the price by $3,950, the company announced this evening.

The standard 2014 BMW i3 electric car starts at $42,275 including delivery, before any Federal, state, or local incentives.

BMW had announced that price in July; tonight it said the i3 version with the range extender will start at $45,200 $45,300, plus a mandatory $925 delivery fee, for a total of $46,125 $46,225.

The i3 range extender is an optional a 650cc, 34-horsepower motorcycle-derived twin-cylinder gasoline engine that adds an additional 80 or so miles to the car's estimated electric range of 80 to 100 miles.

The EPA has not yet released range or efficiency ratings for the 2014 BMW i3.

All BMW i3 models use a 170-horsepower, 184 lb-ft electric drivetrain powered by a 22 kWh lithium-ion battery pack.

2014 BMW i3, 2013 Frankfurt Auto Show

2014 BMW i3, 2013 Frankfurt Auto Show

The range extender fits under the rear load deck on the car's right-hand side.

Standard i3 performance in electric mode includes claims of a benchmark 0-60 mph figure of "around 7 seconds", and a speed of 35 mph after just 3.5 seconds from rest.

Earlier this year, the company released details of the i3's connectivity and infotainment features, as well its detailed 2014 BMW i3's specifications.

Now, BMW continues its practice of listing the i3's prices without netting out Federal tax credits or local incentives, avoiding the confusing and deceptive "net pricing" tactic adopted by other plug-in makers.

While i3 purchasers will have to finalize that total amount, many eligible buyers may be able to get a lower effective total cost after Federal and state tax credits, purchase rebates, and other assorted incentives.

What remains to be determined is how the BMW i3 will perform in range-extending mode--and how much that may differ from its battery performance.

BMW has warned that the range extender is not for daily use, unlike the powertrain of the Chevrolet Volt, which delivers similar performance in either mode.

[UPDATE: Due to an error in an e-mail from BMW announcing the release of pricing information, we reported that the Range Extender option was $3,950 extra--whereas it is actually $3,850 extra. We have corrected the story to reflect the accurate information, and apologize for the error.]


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