Posted on Sun, May. 20, 2007

Every day you stay at a hotel, you might burn enough fossil fuels to release more than 33 pounds of carbon dioxide, the bad boy of global warming, into the atmosphere.

But don't worry. Open your wallet, and all is forgiven, or at least that's the pitch of a growing number of programs.

Among the latest is TravelGreen, announced in February by Sustainable Travel International, a nonprofit company in Boulder, Colo. It markets what it dubs Mini-Green Tags to hotels and guests. The proceeds, it says, will fund conservation and renewable energy, such as solar and wind power.

The idea is based on so-called ''carbon offsets'' that Expedia and other companies offer as optional purchases to customers who travel by air. Such offsets, designed to help counter carbon-dioxide emissions that travel generates, are spreading through the lodging industry.

Since March, Brussels, Belgium-based Rezidor Hotel Group, which runs Radisson, Regent and other chain hotels in the Middle East, Europe and Africa, has allowed guests in these regions to use loyalty points to buy carbon offsets through London-based CarbonNeutral Co.

Leading Hotels of the World, a New York-based marketing association of 440 luxury hotels, recently implemented TravelGreen. And at Bonneville Hot Springs Resort in Bonneville, Wash., which helped pilot the program, some guests attending a conference last fall bought Mini-Green Tags.

But what were they really buying? And should you buy in too?

The answer is complicated. Such efforts are helpful but not a panacea, some activists say.

''These kinds of programs are useful tools for raising awareness about global warming,'' said Jenny Powers, spokeswoman for the Natural Resources Defense Council in New York. ``But the first goal should be to reduce your (carbon) footprint.''

As a guest, you can reduce your footprint by patronizing hotels that reuse towels, recycle water and waste, garden with drought-resistant plants, use solar heat and take other conservation measures.

Look for action, not talk, said Brian T. Mullis, president of Sustainable Travel International: ``Are they engaged in sustainability or `green-washing'?''

Among hoteliers highly regarded for conservation is Denver-based Xanterra Parks & Resorts, which uses alternative energy and tracks waste output at its lodges in Yellowstone, Grand Canyon and other national parks. A few hotels, such as the Orchard Garden in San Francisco, are built to eco-friendly guidelines.

Despite these initiatives, Mullis said, ``The bottom line is that some amount of greenhouse gas is inevitable.''

Just how much takes some calculating, much of it theoretical. On the basis of government statistics on energy use, and figuring that a typical hotel room might be 300 square feet, Mullis estimated that a one-day stay uses 29.3 kilowatt-hours, resulting in the release of 33.7 pounds of carbon dioxide. The cost to offset that with renewable energy is about 48 cents, he added.

Mullis expects Mini-Green Tags to retail for $1. Depending on how the hotel runs the program, fewer than 43 cents might go to alternative energy funded through the program's partners, the nonprofit Bonneville Environmental Foundation in Portland, Ore., and .jMyClimate, a Swiss-based nonprofit.

However hotels handle carbon offsets, there's potential to do well by doing good. Sales of Mini-Green Tags, Mullis said, will develop wind power in Washington and Oregon and build hydroelectric power stations in India.

They also might help eco-guilty guests sleep more easily -- after switching off all the lights.