If a chance to save the world from climate change isn't a compelling reason to embrace environmentally sound technologies, there is one incentive large corporations can't ignore -- money.

The goals of saving cash on energy costs and appealing to consumers who want to use "green" products, not to mention the need to comply with government regulations, are causing a shift of focus for vendors and IT departments.

"There is shareholder return to be gained," Pat Tiernan, vice president of corporate, environmental and social responsibility for HP, said Wednesday during a panel discussion about green trends in IT at Interop Las Vegas. "Frankly, we just see it as a customer demand that we have to meet now and we know we're going to have to meet in the future."

Tiernan was joined by executives from Yahoo, Google, Sun, and Intel, as well as Andrew Winston, author of the book Green to Gold: How Smart Companies use Environmental Strategy to Innovate, Create Value, and Build Competitive Advantage .

Yahoo and Google executives discussed their green goals at length. Yahoo seems to have the more aggressive environmental program, based on Wednesday's session.

Yahoo's green game plan

Yahoo recently announced a plan to become carbon-neutral by the end of this year by making its own processes more efficient and contributing to reductions in carbon emissions around the world.

Carbon neutrality can be achieved by purchasing carbon offsets, in which a company pays a separate company to reduce its greenhouse gas emissions, instead of reducing its own.

While Yahoo does buy carbon offsets, the search engine company does not intend to count those offsets toward its carbon-neutrality goal, says KC Mares, director of Yahoo data centre strategy.

Instead, Yahoo is completing projects on its own, such as one to replace stove cooktops in impoverished areas of the world with energy-efficient models.

Yahoo has made its own operations more efficient in a number of ways. The company builds its own data centres and has third parties build Yahoo computers to its own specifications. "We essentially control the entire footprint, so we can make it very efficient," Mares says. Yahoo uses virtualization to improve efficiency, asks suppliers to deliver everything in reusable packaging, and places data centres where ambient air is cool, lessening the need for air conditioning, he says.

Data centres don't need to be kept at 70 degrees Fahrenheit anyway, as many are, he says. They can survive just fine at 85 degrees, he says. Yahoo doesn't use air conditioning to cool data centers for two-thirds of each year.

Yahoo's green computing goals were driven mostly by users, who are increasingly looking for information on how to help the environment on the Yahoo Web site.

"We're driven mostly by customer demand," Mares says.