And while sustainability in its broader sense also involves social issues--including human rights and fair trade--and economic matters, the committee for now is focusing on the environmental. Some of the focus is, to some degree, defensive, as retailers should explore sustainable techniques before they are compelled to do so, Mohan says.

"This will be like Sarbanes-Oxley, with regulations that we will have no choice but to comply with," Mohan says.

The Leadership in Energy and Environmental Design certification program from the US Green Building Council already has been hugely successful, he notes, and LEED for Retail: New Construction; and LEED for Retail: Commercial Interiors; ratings systems will be issued in the third quarter of this year.

Fortunately, technology is helping. The conference's exhibit hall also held a "Seeing Green" concept store displaying the latest technologies available to retailers to measure and reduce their energy usage. Among the new concepts: digital receipts by allEtronic; paperless coupons from Ecrio; a lower-energy consumption Point of Sale system from Intel; green lighting systems; and energy management systems from NEC. Visitors could quiz themselves on their green knowledge, and viewed a multimedia presentation illustrating the green store of the future.

The display was the fifth annual concept store at the conference, Richard Russo, president, creative director of Clifton, VA-based Hybridia Design and the creator of the display, tells GlobeSt.com.

"Every year we determine what's important in the industry," Russo says. "Last year, we did a pop-up store that was green."

The display itself was sustainable, as well, using a woven floor covering from Merida Merdian, shade fabric, that is PVC and lead-free, made from recycled materials from Roll-A-Shade.

"If you're a larger retail store, there are hardware and software that control everything that goes on," said James Dion, founder and president of Dion Co., a Chicago-based retail operations consultancy, in a practical talk on easy sustainable techniques. "Because this energy is 85% of [a store's] carbon footprint, a 12.8% to 17.5% reduction is a substantial savings. It often pays for itself within two years, and after that, you're just laughing."

Eden Prairie, MN-based Optimal Advantage has created a "sustainable dashboard" for a 1,000-unit retailer that gives a multi-window overview of the chain's highest and lowest CO2-producing and water-using stores. 'This allows us to see the best practices," says Rob Bergh, a vice president of Optimal Advantage.

The data from such an overview also is a valuable tool for CEOs to explain the value of sustainability to their boards. It also shows the breadth of what sustainability entails, Mohan says. "This is a very large area and has tremendous scope, allowing you to cut the energy used in products and operations as much as 50%," Mohan says. "We just have to do it."