The idea started with organic beer. In recent years Scot Case had noticed an explosion in green advertising claims on everything from electronics to, yes, alcohol. So as vice president of the consulting firm TerraChoice Environmental Marketing, he dispatched researchers to investigate whether company claims were verifiable. The result: Only one of roughly 1,000 products examined in 2007 passed muster. "How am I, as a consumer, to know what's accurate?" asks Case.

We wondered the same thing. Like many industries, consumer-electronics companies have been hit hard by the retail recession. But Americans, always eager to cut utility bills, say they're still willing to spend on green. A recent survey by the Consumer Electronics Association found that 33 percent of consumers expect to buy some kind of energy-saving device by the end of next year.

And tech companies aren't sitting idle. New computers from Apple and Asus have been specially designed to be more recyclable, and Philips, which makes electronics including mp3 players and flat-screen TVs, aims to have at least 30 percent of its sales coming from "green products" within the next four years. But with eco-friendly claims tough to verify, we put some of the most heavily hyped green gadgets to the test. Below, our findings.

Last year Jason Cantarella replaced his old TV with a sleek flat-screen model, a $1,200 upgrade. The deal clincher? He saw an ad for an "Eco TV" with a power-saving sensor that automatically adjusts the backlight depending on ambient room light. "I wanted to reward the manufacturer," says the University of Georgia professor.

He isn't alone. More than half of consumers surveyed say they'd pay a premium for a TV with green attributes. Hence one of the big selling points of LCD models: They sip as little as a third of the electricity of tube sets or flat-screen plasmas. It's a quality that "has always been true but is now being marketed as a green feature," says Kimberly Allen of research firm iSuppli.

But some experts say that companies tend to hype energy savings while downplaying potential environmental hazards -- a big deal, given that more than 20 million TVs still end up in landfills each year. Manufacturers still prefer burning, rather than recycling, glass panels. And spokespeople for Vizio and Philips, both of which sell eco-TVs, say they have restricted -- but not eliminated -- the amount of mercury in their screens. The next time your TV goes bust, visit e-Stewards.org to find electronics recyclers who follow environmental regulations.

Computers

Experts say computer makers have stayed ahead of the eco-curve. Just a few years ago, it was challenging to build a computer with a plastic shell that used at least 2 percent recycled materials; today some models boast more than 25 percent. Then there's the mercury, found not only in LCD TVs but also in many computers. Last year both Sony and Dell announced new mercury-free laptop screens.

One of the boldest green claims comes from Apple, which says that its new MacBook features a more energy-efficient hard drive, processor and LED screen -- and slurps "one-quarter the power of a single [60-watt] lightbulb." That wasn't exactly the case when we hooked up a device that measures electricity consumption (see sidebar). While the MacBook used between 24 and 55 percent less power than four comparable laptops when we played a DVD and left a few programs open, it consumed about half the energy of the bulb in our lamp. (A spokesperson for Apple says its test lets the computer idle with no DVD playing.) With more companies making energy-efficiency claims, various groups have begun conducting their own verification tests. The nonprofit Green Electronics Council, for one, will publish its report at ePeat.net later this year.

Mobile Gadgets

What if you didn't have to worry at all about paying for electricity? Some portable gadgets, like cell phones and PDAs, can now channel their energy from the sun -- kind of. For $200 to $400, consumers can buy backpacks, beach totes and even briefcases outfitted with solar panels that charge special batteries, which in turn charge your device. Certainly, these "juice bags" have been a hit with outdoorsy types who enjoy hiking with an iPod or GPS.
But the stiff panels can make the bags clunky. And makers like Voltaic Systems note that cloudy days and indirect light can cut the amount of power solar chargers soak in by up to, oh, 90 percent. "They're supersensitive," says Laura Moorefield, a manager at research firm Ecos Consulting.

No matter how they're charged, most wireless devices get replaced every few years. More than 20 retailers and makers collect old gadgets free (or for a small fee), but why let them sell your refurbished phone or get a tax break by donating it to charity? Apple and Costco offer discounts on new products and gift cards for certain trade-ins, while sites like BuyMyTronics .com and Gazelle.com will send payments via PayPal or check. Now, that's the kind of green we're talking about.