Tucson's veterans hospital is going solar fast, thanks to federal economic stimulus funding.

A 302-kilowatt, sun-tracking photovoltaic array was recently completed at the Southern Arizona VA Health Care System.

And the VA hospital has announced plans to build a 2.9-megawatt, carport-mounted system that is called the largest of its kind in the U.S.

REC Solar Inc., a major provider of large-scale solar systems based in San Luis Obispo, Calif., built the roughly $1.35 million solar tracker array and will begin work on the carport system early next year.

The 2.9 MW carport system, expected to cost about $14 million, will cover seven separate parking areas to become, in aggregate, the largest carport solar system in the country, the company said.

The VA solar systems are part of a renewable-energy push by the agency. The Tucson projects are being paid for from $200 million in funds earmarked for renewable-energy projects through the federal Recovery Act.

The projects, which were competitively bid, are a good investment for taxpayers, said Angiolo Laviziano, CEO of REC Solar.

The carport solar project is expected to pay for itself through avoided energy costs in 10 to 13 years, while the smaller project has a payback period of about 10 years, he said.

The projects also help drive economic development, Lavi-ziano said, citing industry figures that say photovoltaic systems typically create 33 jobs per megawatt of capacity during installation as well as 10 jobs per megawatt during production.

The combined systems at the hospital will significantly offset energy demand from the local utility grid for the more than 900,000-square-foot medical center and cut the equivalent of carbon dioxide emissions from burning more than 420,000 gallons of gasoline annually, REC Solar said.

The 302-kW system, known as a single-axis tracker system, increases overall production by changing its orientation to directly face the sun throughout the day, a first for the VA facilities nationwide, REC Solar said.

Contact Assistant Business Editor David Wichner at dwichner@azstarnet.com or 573-4181.