When it came to designing the power distribution and lighting systems for one of the country’s first LEED Silver Lexus car dealerships, controlling when, where, and how much lighting was used in the facility’s various areas was key to its energy efficiency.
Dave Mungenast Lexus of St. Louis was completed and opened for business in October 2009.
A sophisticated system lighting control system allows the staff to program lights to turn on and off at different times, and program each circuit breaker individually to create different lighting schemes. The panel can be overridden by the night cleaning crew, or can be programmed to go on and off by a remote switch or photo cell.
One challenge to creating the perfect lighting system for this 70,000-square-foot, 2-story dealership was specifying a high dose of lighting in the showroom and service department without consuming too much energy.
Kaiser Electric, the electrical contracting and engineering services firm, selected using F-Bay T8 fluorescent lighting fixtures for additional energy savings and ran an energy model to show compliance with LEED criteria based on watts per square foot.
“The facility had to have brighter, well-lit areas,” says Kaiser Electric Senior Project Manager Mike Murphy. “We were able to accommodate the owner’s needs by grouping the lighting into zones and controlling that lighting to come on only when needed. For example, there are 32 workstations in the service department. We broke the lighting into nine zones so that the workstations being used can be well lit, and those not being used aren’t lighted. We were able to show the owner a savings through lighting control.”
Kaiser also specified occupancy sensors in various areas of the facility to control the amount of lighting used. All of the facility’s private offices and non-common areas, such as the restrooms and training and conference rooms, utilize wall- and ceiling-mounted occupancy sensors.
Lighting the $16 million facility’s parking lot also posed a particular challenge. The parking lot needed to be brightly lit, but the lighting couldn’t bleed into an adjacent park. Plus, there was a restriction on fixture heights. Fifty low-watt, pulse-start metal halide fixtures were specified for the parking lot that use 320-watt bulbs and high-end optics.
Additional environmentally friendly features of the dealership include a water-saving carwash and detail area, low-volume plumbing fixtures to decrease water usage by 30 percent, an insulated roof designed to reduce energy consumption, insulated architectural precast panels, and aluminum curtainwalls with high-performance glazing. Volatile organic compounds (VOCs) in the facility were also reduced through the use of specified materials.
Additional project team members included HDA Architects, Holland Construction Services, and Vertegy.