Wal-Mart is reviewing the performance of its experimental stores based in Texas and Colorado in terms of their environmental performance after one-year in operation. These two stores operate with innovative green technologies designed to reduce operational and construction waste, use recycled and renewable materials, and conserve water and electricity, Wal-Mart said.

"When we conceptualised these two experimental stores, we thought about our environmental opportunities which led our thoughts to our current goals - to be supplied by 100% renewable energy, to create zero waste, and to sell products that sustain our resources and environment," said Charles Zimmerman, vice president of prototype and new format development.  "We see these stores as moving in the right direction for a more sustainable future for Wal-Mart.  We will continue to lead the way in developing sustainable building and business practices." 

Two government-sponsored laboratories are evaluating the experimental outlets - the National Renewable Energy Laboratory is monitoring the Aurora, Colorado, store and the Oak Ridge National Laboratory is monitoring the McKinney, Texas, store. 

"Wal-Mart's experimental stores should radically change the way retail stores are designed, constructed and managed in relation to the environment," said Michael Deru of the National Renewable Energy Laboratory. "These stores contain technologies that will help Wal-Mart minimise their impact on the environment." 

The company said that after one-year some technologies are to be used throughout Wal-Mart and Sam's Club outlets in the US. For example, LED lights installed in exterior signs and grocery, freezer, and jewellery cases use less electricity, contribute less heat and have a longer lifespan. Wal-Mart has decided to integrate these lights into freezer cases in new Wal-Mart and Sam's Club stores nationwide beginning in January 2007. 

"We still consider these stores to be experiments," said Don Moseley, special projects engineer.  "While a number of the experiments have already proven successful, we will continue to monitor and learn from these stores for the full three-year evaluation period. Rather than waiting for the full evaluation period to lapse, we have already determined a need to accelerate implementation of some technologies for new stores."

The company said that one sustainable objective that required further investigation is the generation of renewable power, such as wind turbines. Wal-Mart has found that mechanical problems have interfered with the generation of consistent and continuous power generation, an area that the group will continue to develop.

In the experimental stores, a portion of the energy needed for heating is recovered cooking and motor oil—burned via a waste oil boiler. Heat recovered from the refrigeration racks also heats water used in the system. 

"We are taking the experiences and learnings from this first year of the experimental stores and fine-tuning some of these technologies," said Moseley.  "A number of these technologies are already being implemented in new stores and it is our intention and hope that other technologies will find their way into future business plans.  By continuing to study, evaluate, and monitor these stores over the next two years, we will learn even more about sustainable technologies.  Wal-Mart is very proud to be on the leading-edge of sustainable building and design."