If you've got an old, clunky refrigerator, washing machine or air-conditioning unit you've been meaning to replace, now's the time to toss the ancient relic for a modern, more efficient one.

The wildly successful Cash for Clunkers model that inspired droves of Americans to replace gas hogs with energy efficient vehicles over the summer is being applied to select appliances.

The federal government is providing American Recovery and Reinvestment Act funds to states to spur the acquisition of more energy efficient appliances. California's share of that is $35.2 million. The California Energy Commission is administering the California Cash For Appliances Program, which, like the car program that inspired it, is expected to run out of money quickly.

California's program kicks off on Earth Day, which is Thursday, and can -- theoretically, at least -- be applied to purchases made through May 23. Claims must be postmarked by June 25.

The rebates are $200 for refrigerators, $100 for washing machines and up to $50 for room air conditioners. Checks should arrive a month or so after claims are filed, the state says.

But rebates are available on a first-come, first-served basis while supplies last, so those who dally risk losing out.

Some states have already begun their programs, and if their experience is any guide, Californians had better get a move on.

"When we started (last) week in Phoenix, stores were really busy and by mid-morning, the money was gone," said Home Depot spokeswoman Kathryn Gallagher. "So my advice to consumers would be to get to the store early."

Urner's plans to open at 6 a.m. on Thursday to be ready for shoppers who want to get an early start.

"We're pretty excited about it," said Urner's marketing director David Perkins. "We hope this will encourage people to take advantage of this, and it's the perfect time because there are so many other incentives right now."

Some manufacturers and utility companies such as PG&E are offering rebates, too, and most Energy Star-rated appliances also are eligible for a federal tax credit.

Those seeking a rebate can't just buy any new appliance. They'll need to choose one from a list of approved Energy Star products. Retailers will be able to direct consumers to the appliances on the showroom floor that qualify, or you can check the list online.

To get the rebate, consumers will have to fill out some paperwork and document that their old appliances were recycled by a California certified recycler.

For free or for a small fee, some stores will deliver the new appliance and haul the old one to an approved recycler. Not all stores offer that service, however, so be sure and ask the retailer before you go. If the store is a "platinum partner" in the program, that means it's a one-stop shop that will handle everything, including providing the documents you'll need to file to a claim.

Stores that sell appliances for the most part are praising the initiative. If they are worried about the bureaucracy that frustrated some auto dealerships during the Cash for Clunkers program, they're not saying so.

Asked if she had any concerns about government red tape, Lowe's spokeswoman Jaclyn Pardini paused a moment, then said diplomatically, "We think that it's really important to educate our customers and provide them with resources to make environmentally conscious decisions, and we think that this program provides those types of resources."