More than half a century has passed since an automobile company has launched a large-scale operation in the United States. That’s both daunting and exciting to the folks at Tesla Motors. The Palo-Alto-based company is transforming itself from a low-volume, high-priced maker of luxury electric sports cars to a company that mass-markets more affordable electric vehicles.

Founded in 2003, Tesla Motors launched its first vehicle, the sporty Roadster, in 2008. After selling about 1,500 of the cars, which retailed for more than $100,000, the company is phasing it out to begin production on its new Model S in 2012. The company expects to mass-produce the Model S, which will sell for about half the price of the Roadster.