McKINNEY, Texas - Wal-Mart has announced the opening of a new supercenter in McKinney, Texas, which will also serve as an experimental store, incorporating various energy-saving and HVACR innovations for such a retail building.

The McKinney store will experiment with materials, technology, and processes, which include reducing the amounts of energy and natural resources required to operate and maintain the store.

"We want to make the best use of renewable and alternate sources like wind and solar energy to generate electricity to supplement the power needs of the store," said Don Moseley, P.E., Wal-Mart's experimental projects manager. "The store at McKinney will draw its energy first from on-site resources and systems, and then from conventional utility sources as a secondary service. For example, the waste cooking oil which had been used to fry chicken will be recycled by mixing it with used automotive oil from the Tire and Lube Express to serve as fuel to heat the building."

Other innovations include:

Reflective coating on the building: The west face of the building has been coated with reflective ceramic paint to reduce heat gain inside the building. Energy is saved during the summer months because the heat gain typically experienced by the west face of a building is reflected. The paint reflects the heat and the building requires less mechanical cooling.

Radiant floor heating: Specific areas of this building have a radiant floor heating system to improve comfort. The radiant heating system transfers warmth to help shoppers feel comfortable even in the cool refrigerated section. In addition, it allows the thermostat to be set at a lower temperature than a typical forced air heating system would comfortably permit.

Reduced building height: This building is 12 inches lower in height than a typical Wal-Mart Supercenter. The height reduction meant less building materials were needed to construct this store, and it reduced heating and cooling needs, which lowers energy usage.

Air distribution system: This building is utilizing a concept called displacement ventilation. The fabric ducts have many small holes which can distribute an even airflow along the entire length of the duct. The ducts are mounted 11 feet above the floor and supply air at low velocity and moderate temperature (typically 65-68 degrees F). The supply air quickly mixes with the surrounding air and slowly falls to the floor level. At the floor level the air is warmed by the occupants and other heat sources and rises slowly to the upper levels of the room, which are allowed to get much hotter than the lower 10 feet. The return air opening to the air conditioning unit is located just below the roof deck to return the hottest air. This system is estimated to save about 700,000 kWh of electricity per year, which is enough to power about 70 single family homes for an entire year.

Captured waste heat from refrigeration: Traditional refrigeration equipment expels heat into the atmosphere through air-cooled condensers. In this Supercenter, however, heat generated by the building's refrigeration system is captured and redirected to heat the water used in the restrooms' sinks, and to help heat the water used in the radiant floor heating system beneath the entrance vestibule, cash register area, frozen foods' open cases, and Tire and Lube Express. Thus, less heat is released into the atmosphere, and less energy is needed to heat restroom water and keep the Supercenter warm on cold days.

Publication date: 08/01/2005