Tesla Motors will shortly announce that it is launching a pilot program next week to test the long-promised battery-pack swapping technology for its Model S electric sedan.

The swapping site will be located at a facility across the street from the Tesla Supercharger site in Harris Ranch, California--184 miles south of San Francisco and about 200 miles north of Los Angeles.

DON'T MISS: Tesla Shows 90-Second Battery Swapping For Model S, Details Rollout Plans (Jun 2013)

Tesla CEO Elon Musk teased the news earlier today in a tweet--as is often his practice--saying that the swap capability was "now operating in limited beta mode."

It will involve an unspecified number of Model S electric-car owners, who will be invited to take part in the test.

Tesla Supercharger stations at Harris Ranch, California, in April 2013 [photo: TeslaTap.com]

Tesla Supercharger stations at Harris Ranch, California, in April 2013 [photo: TeslaTap.com]

Details and qualifications of which owners are eligible won't be worked out for another week or so, Tesla told Green Car Reports.

The company says the battery-swap service will initially be offered by appointment only, at a cost that's less than refilling the gas tank of a premium sedan.

We'd have to ballpark that number at $60 or higher, based on a 20-gallon tank and gasoline at $3 or more a gallon.

ALSO SEE: Tesla Says One Battery-Swapping Site Will Go Live In December (Oct 2014)

Tesla uses careful language in its announcement, saying the pilot program is "exploratory work" that is "intended to test technology and assess demand" for swapping services.

The test is "exploratory technology," it says, that presumably would help the company learn what potential exists for this or future battery swap initiatives.

Better Place Battery Swapping

Better Place Battery Swapping

Tesla CEO Elon Musk unveiled a demonstration of the Model S battery-swap capability at a flashy event held in Southern California in June 2013.

The pitch then was that the company could swap a battery pack in less time than it would take to refill the gas tank of a comparable luxury sedan.

MORE: Why Tesla Launched Battery Swapping (Jul 2013)

In fact, the event suggested, two packs could be swapped in that time--with a 90-second swap time portrayed on stage.

The company says now that "for this specific iteration," the swap process will take "approximately 3 minutes"--due to the need to remove the various shields and plates added last year to shield the battery pack from being punctured by road debris.

The company feels it could cut that time to less than 1 minute with changes to the vehicle and further automation of the process.

The pilot program will help Tesla determine whether it should devote time and effort to making those upgrades, depending on the demand for battery swapping versus Supercharging.

The only other application of battery swapping for electric passenger cars thus far was the now-defunct Better Place project in Israel, which at its height had more than 20 swap stations in operation.


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