Wal-Mart Stores Inc. will open a second experimental store in Aurora, Colo., on Nov. 9 to test more efficient water and energy systems and other environmental projects.

The store will test solar energy use in a retail setting as well as wind energy projects. It also will use waste oil boilers that will burn used motor oil and vegetable oil. Other features include an environmentally friendly gas station, waterless urinals and the use of recycled material from a local airport in the building´s foundation and monument signs.

Wal-Mart opened a similar experimental store in July in McKinney, Texas. The company has commissioned the Building Technology Center at the U.S. Department of Energy´s Oak Ridge National Laboratory to study the impact of the 26 environmental projects at the McKinney store.