SANTA CLARA -- For more than a half-century, the San Francisco 49ers' colors have been red and gold. But as the team prepares to move into its new $1.3 billion stadium in Santa Clara next year, a new color is emerging -- green.

Levi's Stadium will have 1,162 solar panels, high-efficiency toilets and sinks that use 40 percent less water than California building codes require, and a 27,000-square-foot "living roof" featuring native plants. The 49ers say their new home will be a model of ecological efficiency that will make fans in environmentally conscious Northern California embrace the project the way that Sierra Clubbers hug old-growth redwoods.

But how much is genuine -- and how much is eco-hype?

It depends on how you look at it.

"It's not window dressing. This is real," said Jack Hill, the project executive overseeing construction. "The 49ers are very proud of it. It's the right thing to do."

More than 75 percent of construction materials are being recycled, Hill said. The stadium is located near light rail and other transit. The team is aiming to serve mostly locally produced food and plans to put sustainable bamboo woodwork in the luxury suites. The field's sprinklers will spray recycled water when the stadium, now 70 percent complete, opens in August.

Critics who never wanted the stadium built, however, say they aren't impressed.

"The whole green thing is kind of a publicity campaign," said Deborah Bress, a spokeswoman for Santa Clara Plays Fair, a group that opposed the project when voters approved it in 2010.

"It's wonderful they are doing the solar and green roof," she said. "But the stadium impact on the environment is so much bigger."

To conserve electricity, the 49ers are installing LED bulbs in 40 percent of the stadium lighting. But team officials canceled plans to put the high-efficiency bulbs in the huge field lights because of concerns from broadcasters that the technology might alter the color of the players' uniforms on TV.

Nobody wants to see a pink-shirted linebacker, no matter how many greenhouse gases his team is offsetting.

Construction workers are now installing 1,162 solar panels on the western roof of the stadium and on the roofs of three bridges across San Tomas Aquino Creek. Those SunPower panels will generate 375 kilowatts of electricity, roughly as much as 100 home rooftop systems.

That, alternative-energy officials say, will make the stadium a solar showplace.

"Given the iconic nature of football stadiums, they end up being wonderful display cases for new technology -- in this case energy technology," said Tom Gros, senior vice president of New Jersey-based NRG Energy, which is installing the solar system.

Still, the solar panels won't provide anywhere near enough electricity to satisfy the stadium's needs on game days. If the electricity needed for a typical game is roughly 3 to 7 megawatts, as expected, that means the solar panels will provide less than 10 percent of the electricity used during game day.

And other NFL stadiums have larger solar arrays. Lincoln Financial Field, where the Philadelphia Eagles play, has 11,000 solar panels, generating eight times as much electricity as the 49ers' solar panels will. Similarly, the Washington Redskins stadium, FedEx Field, has a solar system five times as large as Levi's Stadium.

The main reason is that many of the panels sit on parking lots owned by the Eagles and Redskins. But the 49ers don't own most of the lots their fans will use.

Niner officials, however, emphasize that their stadium will be a "net zero" energy user -- meaning that all the solar power generated in a year will be enough to run the stadium during its eight regular-season home games -- but not playoff and exhibition games or non-game events such as concerts.

But the vast majority of electricity will come from a utility, Silicon Valley Power, and the team hasn't said yet whether it will buy "green power" generated by wind and solar energy. That costs about 10 percent more than standard electricity.

"We haven't determined that yet," said Heath Blount, regional director for BrightWorks, an Oakland company working on the project.

The team is shooting for a very high environmental pedigree. Owner Jed York has said he wants the building to be the first NFL stadium to achieve gold status from the U.S. Green Building Council. Soldier Field, where the Chicago Bears play, is certified silver. So is AT&T Park, home of the San Francisco Giants.

To get the gold, the 49ers have to earn at least 39 points under the council's rigorous scoring system. So far, they have 42, Blount said.

The team is still working on other issues. Hill, for example, says it still doesn't know how many electric-vehicle charging stations it plans to install. And it hasn't yet made available energy comparisons with Candlestick Park, where the team plays now, so that people can compute which stadium has a larger carbon footprint.

Nevertheless, the new green features are winning plaudits from experts.

"When 68,000 people go to a stadium and see the 49ers trying to make a difference, there is evidence, I think, that they will start thinking about sustainability and the environment also," said Jeff Koseff, a professor of civil and environmental engineering at Stanford University.

"And what would you rather be talking about if you were the NFL," he added, referencing the league's recent hazing controversy, "environmental sustainability or Richie Incognito?"

Paul Rogers covers resources and environmental issues. Contact him at 408-920-5045. Follow him at Twitter.com/PaulRogersSJMN.

LEVI'S stadium
GREEN FEATURES
1,162 solar panels
27,000-square-foot "living roof"
Recycled water in toilets and irrigation
High-efficiency LED lighting