Some travel booking websites are trying to make it easier for consumers to be environmentally friendly.
Orbitz is featuring energy-efficient hotels at www.eco.orbitz.com. These properties have earned an "Energy Star" label from the U.S. Environmental Protection Agency because they use nearly 40% less energy than average buildings and emit 35% less carbon dioxide.
The website also makes it easy to book hybrid car rentals, take a volunteer vacation or purchase carbon offsets for your travel.
Expedia has a new "Going Green" store. The online store at www.expedia.com/gogreen also allows customers to browse for environmentally friendly hotels, hybrid car rentals and carbon offsets.