The Dorris Loft is a charming condominium complex in the Central West End of St. Louis, with convenient access to the thriving Cortex hub, light rail transportation and St. Louis University. Originally built in 1912 by the Dorris Motor Car Company to house its state-of-the-art production area, sales department and showroom, the company closed in 1926 due to competition from Detroit, and was later used by several Cadillac dealers before being converted to loft residences in 1985.
The trustees of Dorris Loft were interested in lighting upgrades in the common areas, including the garage, parking lot, clubhouse, and courtyard. While each of these areas used traditional incandescent halogen or metal halide lamps that were easily replaced by higher efficiency LED lamps, the garage offered the greatest opportunity for savings.
There were sixty 8’ dual-lamp T12 fluorescent lamp fixtures in the L-shaped parking garage, though half of the fixtures had no lamps. These lamps lit the garage 24 hours a day, seven days a week, and the T12 is the most inefficient fluorescent lamp still available. Rather than replacing the entire fixture, we found a more cost-effective solution that left the existing fixtures in place, but simply replaced the reflector pan and electronics to accommodate four 4’ LED lamps, reducing costs significantly. In addition, the 57W ballasts were bypassed in all fixtures, adding even more savings than originally projected with the lighting upgrades alone.
The new lighting was wired to include three banks of 10 fixtures, each controlled by a separate occupancy sensor optimally positioned to capture movement, with a single fixture running 24/7 to provide some lighting in the garage at all time. The controls automatically turned on the rest of the lights in that portion of the garage whenever the sensor detected movement, including cars or people entering the garage from multiple points. The lights controlled by the sensor are programmed to automatically shut off after five minutes of inactivity. So in addition to saving over 33,800 kWh of energy from the higher efficiency lamps and bypassed ballasts, even more energy has been saved by turning 90% of the lighting off when not in use!
The garage certainly contributed the most savings on the entire lighting project, but this also saved maintenance costs. The 36 can lights in the exterior walkways required a 12’ step ladder to replace lamps, which usually had to be replaced every 2-3 years, and the metal halide lamps also required replacement after five years or so.
Unfortunately Ameren no longer offers rebates on outside lighting, so this project was among the last to be awarded incentives to do what already has a strong payback. If you still have incandescent lights with no controls, you’re have a great opportunity to save!