No one's asking you to spend more money just to be planet friendly.

But a national campaign called the Big Green Purse challenges women to shift at least $1,000 of their household money in a year — that's money you'd already be spending — on cleaner, greener alternatives.

You could switch from cotton bed sheets and buy a set made from bamboo for everyone in your family, along with enough compact fluorescent light bulbs to illuminate your home for several years. Or, replace your energy-sucking refrigerator with an Energy Star model.

Better yet, be an overachiever and trade in your SUV for a hybrid.

"We're switching little by little," says Donna Risch, 54, who was planning to sign up at www.biggreenpurse.com.

As light bulbs in her Bellevue, Tenn., home burn out, she's replacing them with energy-efficient compact fluorescents. She's also switched to a green brand of dishwashing detergent and tries to purchase most of her fruits and vegetables from local growers.

"We believe Al Gore that we're in trouble," Risch says. "We have grandchildren, and we want our grandchildren to have a better world than it looks like it will be if we don't do something."

Risch also covers her gray strands with environmentally friendly hair dyes she found at Whole Foods. "My hair stuff will probably be enough" to reach the $1,000 threshold, Risch jokes.

PURSE HOLDS POWER

The campaign focuses on women because they hold the power of the purse in most families: Women decide how to spend 85 cents of every dollar in the marketplace.

The goal of the green purse effort, which started last April on Earth Day, is to motivate a million women to make the shift, says Diane MacEachern, the founder and CEO of Big Green Purse, which aims to empower women to use their marketplace clout to protect the environment.

"The way we spend our money has a direct impact on what manufacturers produce," MacEachern says. "So I believe consumers should tell manufacturers what to make, rather than have them tell us what to buy."

The Web site offers tips on what to look for when you're eco-shopping, and, if you sign up, you get a spreadsheet that helps you track your purchases. If successful, the effort will result in $1 billion redirected to greener choices.

Bank teller Sande Sullivan, 44, logged on in December to register, joining 1,500 other women from around the country in the movement.

"I am also trying to recruit my coworkers," Sullivan says.

START SMALL

The Nolensville, Tenn., woman is starting small, like buying canvas bags to carry her groceries, switching to bamboo bed sheets — bamboo is a fast-growing renewable resource — and buying reusable plastic plates she found at Wild Oats to replace the paper plates her family sometimes uses.

For Christmas, she cut back on buying a lot of "stuff" and instead gave to charities in the name of her four children.

Her children's interests, in part, inspired the charities she picked. For one son, 18, she made a donation to Invisible Children, which helps Ugandan orphans, after he watched a documentary at school.

One daughter, 20, got a donation made to World Vision, which will give two chickens to a poor family. Sullivan also donated to Happy Tails, an animal shelter, for her animal-crazy 10-year-old son, and to St. Jude Children's Research Hospital for another daughter.

Sullivan will hit the $1,000 goal if the family trades in its minivan for a hybrid in 2008.

"With all the growing environmental problems, everybody thinks they can't do their part," Sullivan says. "But that's the kind of thinking that keeps us from doing anything."

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