WASHINGTON - A key landmark is taking part in going green. The U.S. Capitol is undergoing a massive makeover.

Up on the Hill these days, lawmakers aren't just arguing over green, they're going green.

"I think it's one of the best kept secrets right now in the government," said Allison Rogers with "Green the Capitol."

It's a massive effort to become an environmentally-friendly Capitol and way beyond changing 13,000 light bulbs or double-sided copying.

In the cafeteria, plastic and styrofoam have been banned. Even the water bottles are now made from corn. Everything that gets tossed gets run through "the pulper."

All the waste is shredded into compost. At 240,000 meals a year, that's a lot of future fertilizer.

"It's actually astonishing, how much of a difference you can make," said Perry Plumart with Special Projects.

Three thousand smart strips make sure when computers sleep, the rest of the electronics do too. energy efficient vending machines save $25,000 a year. Also, 100 percent of the Capitol's electricity now comes from wind power.

The system's plant no longer uses coal. Natural gas is what heats and cools Congress these days.

"You get the response of, 'whoa! The government is doing this?'" shared Rogers.

The goal is to cut energy consumption in half over the next 10 years. Updated lighting and water fixtures will save $3.4 million each year.

Recycling already paid for a hybrid truck. While it'll be years, maybe decades before the savings erase the initial costs, there is a message here.

"We can't ask the American people to go green if we don't do it ourselves," said Karissa Marcum with "Green the Capitol."

They're not just greening the Capitol inside. The Dome is getting a new lighting system, too, that'll make it look brighter and show more detail. Though it's got a hefty price tag of more than half-a-million dollars, it'll eventually reduce the annual cost of lighting by almost 70 percent.

 Email To Friend