• by Sarah Mahoney  @mahoney_sarah, March 19, 2008

Wal-Mart Stores has come up with its most energy-efficient store design yet, and says the new prototype will use up to 45% less energy than its baseline Supercenter.

And experts say that Wal-Mart, which has aggressively pursued energy-saving innovations, may finally be winning the perception war. Although environmental groups often accuse it of being the consummate corporate green washer, its energy efficiencies are undeniably cutting-edge, and will be tough for many retailers to replicate.

This prototype, for example, called the HE.5, draws on lessons the retailer learned from previous high-efficiency stores, and is the first in a "new series of prototypes designed for specific climates," the company says. Geared specifically toward the western U.S., it "features advancements in heating, cooling, refrigeration and lighting to conserve energy and reduce greenhouse gas emissions," using "an integrated water-source format system." Water is cooled naturally by pumping it through roof-mounted cooling towers, which is then piped under the floors to lower the temperature in the store.

Such innovations give Wal-Mart plenty of competitive advantages, says Jerry Yudelson, a Tucson, Ariz.-based green building consultant and author of The Green Building Revolution.

"Wal-Mart is an aggressive cost-cutter, and once it realized there were potentially tens of millions of savings in operations, energy efficiency had great appeal," he says. "And it gives Wal-Mart an opportunity--both in terms of public relations and political relations--to be seen as a different kind of company."

Besides, he says, while Wal-Mart has been a leader, more and more retailers are taking a pragmatic, forward-looking approach to green building. "No matter who gets elected in November," he says, "it's likely we'll see some introduction of carbon controls. And for multinationals doing business in Europe, as Wal-Mart is, where controls are more strict than in the U.S., it makes sense to get ahead of the curve--what's happening in the EU will drive what happens in the U.S."

Many other retailers are hurrying their greener designs along. Some, such as Best Buy and PNC banks, have already made some form of LEED certification--the highest standard for green buildings--part of their building goals. And, he says, "I wouldn't be surprised if by 2010, Wal-Mart was involved, in some way, in the LEED program."

Wal-Mart says its new store will "ultimately help Wal-Mart reach its goal to design and open a viable store prototype that is 25-30% more energy efficient by 2009."

Its initiatives come as environmentalism becomes more and more mainstream. Market researcher Mintel, for example, says that more than one third of adults (36%) claim to "regularly" buy green products, compared with 12% just 16 months ago.

And the number of people who "never" purchase green products has been cut in half in that period, with only 10% of American shoppers falling into that category, down from 20%.