Tesla Motors has reached a “fundamental turning point,” the company said in its quarterly earnings statement today, transitioning from a small-volume maker of boutique electric cars to a mass-production company capable of building and selling 20,000 or more electric cars per year.

That’s an optimistic statement, to say the least. If Tesla reaches its 2013 production target, it’ll be two orders of magnitude larger than the company’s third-quarter production: It made just shy of 350 Model S sedans and sold about 250 of them last quarter. It also sold 68 of its Roadster sportscars. Total automobile sales produced gross revenues of about $50 million.

While that number is small (and implies a wallet-flattening average sales price of $200,000 per car), the production was concentrated in the last couple weeks of the quarter, when Tesla says it reached a peak of 200 cars built per week. If it can maintain that rate, it will be able to produce 10,000 cars per year, which it says is the number it needs to become cash-flow positive, assuming it sells those sedans for the expected price of $57,400 and up. If you want to buy a Model S today, however, it’s much more expensive: $95,400, according to a Reuters report.

Tesla has spent much of the past year retooling its main factory in Fremont, Calif., the former NUMMI plant owned by Toyota, a slow and capital-intensive process, assisted by a $465 million loan from the U.S. Department of Energy and a $222 million follow-on offering. (The company initially went public in 2010.) It has also run into competitive trouble, with other automakers filing multiple suits claiming that its manufacturer-owned showrooms are contrary to U.S. law.

Tesla is confident it can reach a production rate of 400 cars per week next month. In other words, in 30 days it will be producing more cars in one week than it did in all of the last quarter. Financial analysis website Seeking Alpha, backed up by a Morgan Stanley report, seems to be confident of Tesla’s ability to deliver on its promises and recommends buying the stock.

That rapid ramp-up is key to the company’s success. In three more months, Tesla will deliver another quarterly report, and then we’ll learn whether its optimism is justified or just an empty promise.

Top photo: Elon Musk watches robot arms in the Tesla factory. Credit: jurvetson via photopin

The New United Motor Manufacturing Inc. facilities in Fremont, Calif. spans 5.5 million square feet and will have to be refitted for production of Tesla’s Model S sedan (pictured below), which is slated to begin in 2012. The new factory marks the company shifting gears to focus entirely on Model S — it will cease production of the Roadster in 2011, though supplies are expected to last through 2012.

The process of retooling the factory has been in the works for some months now, said Tesla spokeswoman Khobi Brooklyn. Workers have been bringing in and installing new equipment, and Tesla is looking to hire and train 500 new workers, a process Brooklyn said is likely to continue into 2011.

Though there’s no set timeline for when the factory will go into production and all of the preparation work will be completed, Tesla will be holding a factory unveiling for press and invited guests on Oct. 27, which CEO Elon Musk will attend.

“We’re continuing to move equipment in, and that will keep going for many months,” Brooklyn said. “We’re really in the initial phase of this.”

Tesla has a Palo Alto manufacturing facility (pictured) that makes battery and motor packs specifically for the Roadster, but the company is refocusing on production and sale of the Model S, an all-electric sedan that has more mass appeal than the Roadster, a racy sports car that costs upwards of $100,000.

The Model S, on the other hand, seats seven, has a 160-, 230- or 300-mile range (depending on the battery pack option) and starts at $49,000 after a $7,500 federal tax credit. The company is taking reservations, which require a refundable fee of $5,000.

“The Model S is the premium sedan evolved. It will raise the bar of vehicle efficiency, meet the highest standards for safety, and provide more cargo space than any other sedan,” wrote Gilbert Passin, Tesla’s vice president of manufacturing, in a blog post detailing the manufacturing process for the sedan.

Car and Driver previously reported the Model S would go into production in the third quarter of 2011, and the company plans to produce them at 20,000 cars a year.

Tesla also previously purchased $15 million in factory equipment from Toyota.

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