DAYLIGHTING (SKYLIGHTS/DIMMING)
- Every facility Wal-Mart builds today from the ground up includes a skylight/dimming system. As daylight increases, skylights allow Wal-Mart to dim the lights, or even turn them off, thereby reducing the demand for electricity during peak hours.
- Nationwide, there are nearly 600 Wal-Mart Supercenters, SAMS CLUBS and Neighborhood Markets with this system, resulting in an annual savings of about 250 million kwh a year, enough to power approximately 23,000 homes.
- No other big box or national retailer has a similar daylighting system. Other stores may turn off some lights, but only Wal-Mart automatically dims all of the lights as the daylight contribution increases.
- Based on an in-house study completed in 1998, Wal-Mart found that its daylighting system utilized about 25 to 35 percent less than other big box competitors.
- Nationwide, Wal-Mart builds or converts 200-300 facilities each year. All new stores will include the daylighting system.
HEATING & COOLING
- Wal-Mart uses high-efficiency heating and cooling units. While the standard energy- efficiency ratio for heating/cooling units is 9.0, Wal-Mart units have an energy-efficiency ratio of between 10.1 and 11.0.
- The heating and cooling of Wal-Mart stores worldwide is centrally controlled in Bentonville, Ark., enabling Wal-Mart to significantly reduce energy consumption.
WHITE ROOFS
- Since the mid 1990s, all Wal-Mart stores built in California have white membrane roofs. The high solar reflectivity of this membrane results in lowering the cooling load by about 8 percent.
INTERIOR LIGHTING RETROFIT PROGRAM
- All new Wal-Mart stores and Supercenters utilize T-8 low-mercury fluorescent lamps and electronic ballasts, the most efficient lighting system on the market.
- Unlike other fluorescent lamps, low-mercury T-8s are not considered a hazardous material. Out of concern for the environment, Wal-Mart voluntarily recycles its lamps, instead of simply placing them in a landfill.
- By retrofitting stores with T-8 lighting systems, energy load is reduced by approximately 15 to 20 percent.
DOING OUR PART TO CONSERVE ENERGY - THE CALIFORNIA EXAMPLE
- Existing conservation measures at Wal-Mart stores and SAMS CLUBS in California alone offset the states electrical grid by 4.5 million kwh a month, enough power to keep the lights on in 5,000 homes.
- In January, Wal-Mart voluntarily reduced interior lighting in 113 California stores without skylights by turning off every third fixture. This change alone is estimated to save 68,000 kwh a day, enough power to supply 75 homes a month.