CLTC UC Davis Parking Garage Case Study:

 

Development Partners: California Energy Commission’s Public Interest Energy Research (PIER) Program, California Lighting Technology Center, Full Spectrum Solutions, Inc., Watt Stopper/Legrand

Demonstration Partners: UC Davis Energy Efficiency Center, UC Davis Facilities Management

UC Davis Parking Garages Shine with Smart Fixtures

California Lighting Technology Center (CLTC) partnered with California Energy Commission′s Public Interest Energy Research (PIER) Program, Full Spectrum Solutions, Inc., and Watt Stopper/Legrand to develop a bi-level occupancy based induction luminaire for exterior deck or ceiling mounted applications. This innovative product reduces energy consumption and maintenance costs. The bi-level luminaires reduce light levels to 50% when the space is unoccupied, saving energy and reducing light pollution. When motion is detected, they return to full brightness. To test the product, eight fixtures were installed at the UC Davis North Entry Parking Structure. Data collected from the demonstrations indicates a 30–40% reduction in energy consumption. The test was completed as part of the UC Davis Smart Energy Initiative Garage Lighting Project, a statewide energy saving initiative in collaboration with the UC Davis Energy Efficiency Center.

Driver and pedestrian safety are key concerns in parking area lighting design. Until now, the accepted belief was that a brightly lit area is safer. To the contrary, current research indicates that a system that responds to occupancy provides more beneficial information than one that is always in the same mode. If a security guard is overseeing a garage that is at 50% brightness and the lights come to full power in specific places, there is a targeted area to monitor. Additionally, the high correlated color temperature (CCT) of 5000 K provides for better visibility and color differentiation. Blue and green cars that were difficult to distinguish between under the former high-pressure sodium lights are now clearly rendered with the light from the induction lamps. Research has also shown that bluer light is more effective in low light level situations.

Energy savings are only one portion of the overall reduction in resource use. The EverLast® 100 Watt Induction Lamp is designed to last for 100,000 hours, which translates to approximately a 20 year lamp replacement cycle. Maintenance costs are reduced due to a longer lamp lifespan compared to alternative lamp choices. When a luminaire requires little or no attention, maintenance resources may be reallocated. Emissions from vehicles used to replace lamps are minimized. Landfill waste from failed lamps, including mercury, is also reduced. Over the life of the induction lamps, more than seven of the traditional lamps would fail. This means that more than 8000 lamps will be eliminated from the waste stream after the new lighting system is installed.

LED products show great promise in the energy efficient lighting development effort, but the high first cost is still an obstacle for many buyers. Induction lighting offers a lower first cost alternative combined with significant energy use reduction. Facilities managers with immediate lighting needs are looking for proven, market-ready technologies. The energy savings demonstrated at the test site makes induction lighting an ideal technology for retrofitting existing parking structures at campuses, shopping centers, and urban city centers. After evaluating the results from the initial installation, UC Davis Facilities Management has committed to retrofitting four large parking garages that contain more than 1000 luminaires.

The impact of this commitment is two-fold. Facility managers will see the cost and maintenance savings. The estimated annual energy savings for the four structures is $77,127, based on the discounted university utilities rate of 9¢ per KwH. Maintenance savings are not included in this estimate. Employees, students, and citizens will continue to use a well-lit parking structure, but will be able to see the stars a little clearer if they live nearby or pass by an unoccupied garage at night. As the adoption of more efficient lighting technologies increases, and awareness and acceptance of multi-level lighting increases, energy consumption will decrease and help UC Davis and the state of California reach their efficiency goals. In five years, perhaps we will all wonder who left the lights on when we pass by a fullylit parking area at night. This project is one step towards that goal.