Napa, California, located north of San Francisco, has completed an LED-lighting installation on its Maxwell Bridge that crosses the Napa River. The bridge was rebuilt in 2005 and is a local architectural landmark. The transition from high-pressure-sodium (HPS) lights to BetaLED solid-state lighting (SSL) has reduced energy use by 9180 kWh per year – a 31% savings.
|Uniform surface lighting on the Maxwell Bridge|
While energy savings were an important goal for the LED project, the city was also concerned with the aesthetics. “The real test of success was when we lit the bridge. There was just no comparison of the quality of the LED lights to the HPS lights. This confirmed for us that the whole project was worth it,” said Steve Crego, City of Napa Electrical Supervisor.
|Aerial view of LED lighting|
Nearby photos include both before and after aerial shots and a shot captured on the bridge surface. That surface photo demonstrates both the uniformity and brightness of the LED installation. The city said that the lighting improves pedestrian safety and motorists’ visibility and notes the importance of continuous light levels for the entire length of the bridge.
“The 90-LED LEDway street lights recently installed along the length of the bridge deliver enhanced color quality, uniformity and optimized illumination performance to help increase visibility and safety,” said Kevin Orth, Vice President of Sales for BetaLED. “The City is realizing significant energy savings from the retrofit while meeting the Caltrans highway lighting specification.”
|HPS lighting on the bridge|
Napa worked with the Pacific Gas & Electric (PG&E) utility in choosing and installing the LEDway lights. The 60 new 90W SSL luminaires replaced 200W HPS lights. “Because of PG&E’s extensive experience in street light installation and maintenance we’re able to help municipalities with project design, installation and billing updates – saving them time and money,” said John Sofranac, PG&E street and outdoor lighting manager.
The city began contemplating a relighting project in 2009 when it received a grant from the US Department of Energy (DOE) and established the City of Napa Sustainability Program. The bridge project was just completed this spring.
Other Napa projects
According to the local Napa Valley Register newspaper, the Maxwell Bridge is just part of the LED story in the region, although perhaps the most visible one. The bridge project was part of a larger 148-light retrofit with LEDs that also included some local streets.
Moreover, Napa is planning to convert 146 additional street lights according to the local paper. Once that second project is complete, the city could save $23,000 annually in energy costs. The city’s Crego also expects significant maintenance savings.
Still Napa is a good example of the potential that remains for LED installations and far-greater energy savings. Even when the city completes its next project bringing the total of LED lights to 294, that number is a small percentage of the 6000 lights that the city owns.
Millbrae LED installation
In related news in the Northern, California region, the city of Millbrae has completed its first major LED-street-light project also using BetaLED fixtures according to the New Streetlights website. A $112,630 DOE Energy Efficiency and Conservation Block Grant (EECBG) funded the installation of 278 LED street lights.
Millbrae projects annual energy savings of $10,000 via a 68,791 kWh reduction in energy usage. That corresponds with a reduction in greenhouse gases by 36,047 pounds per year. The LED lights will use 50 to 60% less energy than the HPS lights that were replaced.