Plans by two out-of-state companies to redevelop Ford Motor Co.'s abandoned Wixom plant into an energy park could help further solidify Michigan's effort to become an alternative energy hub, some industry observers say.

But the $725 million project hinges on Xtreme Power of Austin, Texas, and Clairvoyant Energy of Santa Barbara, Calif., winning federal loans and state tax breaks to refurbish the 318-acre property.

The project could create about 4,300 jobs. It also could establish a North American headquarters in Wixom for Oerlikon Solar, a Switzerland-based leader in thin-film solar technology, said Phil Horlock, chairman and CEO of Ford's real estate division.

Clairvoyant Energy is working with Oerlikon to bring the Swiss company's solar manufacturing technology to the United States. Clairvoyant plans to make utility-size solar panels at the site. Xtreme Power builds large-scale battery systems for storing renewable power.

Michigan lawmakers are trying to bring the deal to fruition. Both companies also plan to seek federal stimulus money with the Department of Energy and are considering sites in other states. They will select a site before Sept. 14, the deadline for applying for a federal loan.

A specialized tax credit tailored to the companies for a maximum of $100 million over four years was unanimously approved by a state House committee Wednesday but no vote was taken.

In a related development, the Senate Finance Committee passed a package Wednesday afternoon that would expand Michigan Economic Growth Authority tax credits this year.

The state is brushing up against its limit on the tax breaks for the year, and Gov. Jennifer Granholm and state economic development officials are pushing for an increase so Michigan does not lose a business attraction tool for the next few months.

Executives for the two energy companies said renovation of the site could begin almost immediately and production could start by late 2011.

"We have a unique opportunity in Michigan," said Carlos Coe, the CEO of Xtreme Power. "The infrastructure is in place there, and we can co-locate with other renewable energy manufacturers."

He said several other states were vying for the project but he declined to name them. Xtreme power develops and manufactures large-scale battery storage systems for use with renewable power sources, such as wind turbines and solar panels.

David Hardee, CEO of Clairvoyant Energy, said the chance to work with other alternative energy manufacturers is the key to the project.

The project is expected to attract other renewable energy companies. A research and development center also will be located at the site and the firms will partner with a Michigan university. The companies are working with University of Michigan, Michigan State University and Wayne State University.

"This could possibly become what Silicon Valley was to California," Wixom Mayor Kevin Hinkley told the House committee.

Creating an industrial park specifically for alternative energy businesses is a novel concept that could help generate some industry buzz for Michigan, said Dan Radomski, vice president of industry services for NextEnergy, a business incubator in Detroit.

"You haven't seen a whole lot of clustering in the renewable energy sector," he said. "If we're able to pull this off, it will be widely recognized as a kind of hub."

Granholm has made growth in renewable energy a cornerstone of diversifying Michigan's auto-centric economy. Earlier this month, Michigan and Detroit's Big Three automakers won more than $1.3 billion in federal grants to support the next generation of batteries and electric vehicles.

Clemente said the bill that passed Wednesday was rushed to committee to help meet the energy companies' mid-September deadline. "Usually we want a longer filtering process but in this economy we expect cooperation," he said.

Establishing a solar manufacturing business can be a risky proposition with countries like China and Taiwan churning out cheaper products on the market, said Adam Krop, a solar analyst for Ardour Capital Investments, LLC in New York.

Still, with the federal government promoting renewable energy, the United States has become the "next frontier" for many global solar companies and thin-film solar technology stands out from more traditional wafer-based equipment, Krop said.