Union Pacific said Friday it is selling two big chunks of land next to the Tesla Motors (TSLA) plant in Fremont, a decision that bolsters the city's hopes for a technology-oriented transit village near the factory.

The land, 94 acres on the north side of the plant and 53 on the south, could become a hot ticket, local realty agents said.

"It's tough to find any large parcels in Silicon Valley," said Chris Shaffer, a senior vice president with Cornish & Carey Commercial, a realty brokerage. "That will make that site very attractive. And it's a good location."

The property is between interstates 880 and 680 and a short distance from major routes such as Warm SpringsBoulevard. Plus, BART intends to open a Warm Springs station nearby.

In December 2010, rail giant Union Pacific bought the property from New United Motor Manufacturing, the principal owners of the old NUMMI auto factory, and said it planned to develop the property as a freight and railroad complex. That news worried city officials, who saw the land as vital to the city's economic development.

But Union Pacific appears to have changed course. The company has begun to scout for one or more developers that might want the property.

"Though the parcel we own in Fremont would be conducive to a rail facility, we have no definitive plans to build a full scale terminal at this time," said Aaron Hunt, a spokesman for Union Pacific.

Anxious to replace the 4,700 jobs that vanished when the NUMMI factory closed in April 2010, Fremont officials were concerned that a rail-focused complex could thwart its vision of the kinds of jobs that could emerge on the vacant parcels.

"We would like to see some sort of mix of high-density residential and transit-oriented development that would generate employment," said Christina Briggs, an economic development manager with the city of Fremont.

"We want to focus on emerging technologies," Briggs added. "Tesla could be a major anchor for the development of that area."

The recent implosion of Solyndra and the loss of its 1,100 green manufacturing jobs has intensified Fremont's efforts to find new sources of jobs.

Yet Union Pacific won't wait indefinitely for a buyer. The company said it would market the northern 94 acres for 12 to 15 months. It did not set a deadline on the other parcel.

"If a sale is not accomplished in that time, we may move forward with planning to put the property to rail-related uses as originally conceived."

BART stations such as those in downtown Oakland, Pleasanton, Walnut Creek and Pleasant Hill and Concord, along with those in downtown San Francisco, have become magnets for companies whose workers prefer public transit.

Similarly, transit hubs on the Peninsula and in Santa Clara County have beckoned developers and big office tenants.

"The Caltrain line has definitely become a valuable draw," said Craig Fordyce, a senior vice president with Colliers International. "Properties near Caltrain are getting a lot of attention from tenants. You have a lot of younger workers who want to take transit."

If buyers emerge for one or both properties, they will need to have some staying power. That's because the markets remain sour for new residential, office and retail projects.

"If you get a developer with a longer window, once the economy picks up and you get BART in there, this should be a great site," Shaffer said.

Contact George Avalos at 925-977-8477. Follow him at twitter.com/george_avalos.

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