MaineDOT I-295 Case Study
Although the interstate is a reliable path to beautiful beaches, its outdated lighting created concern. “Our main goal is to provide a safe transportation system for the state of Maine,” said Ron Cote, MaineDOT Electrical Supervisor. “The previous lighting illuminating I-295 was from the seventies, so it was definitely time to find a more efficient and modern light source.”
Technology Advancements Create Opportunity
The state’s outdated high pressure sodium fixtures were consuming 3,000-watts per tower, resulting in energy costs of $200 monthly per tower. As a way to reduce cost, the lighting was shut off from 11 p.m. to 6 a.m., which was not an ideal solution for nighttime drivers.
The MaineDOT needed a cost-effective solution that would allow lights to remain on throughout the night. Longevity and energy savings were also key priorities when searching for new fixtures. Additionally, existing high pressure sodium lighting was known for creating numerous bright spots and glare.
“The high pressure sodium lighting was not evenly distributed onto the road,” said Cote. “In some spots it was too bright, which created a glare, and in other spots it was too dark. We were looking for a light source that would provide lower maintenance and a whiter light. It was also taken into account that the new fixture had to be full cut-off and provide an even light distribution.”
With these goals in mind, MaineDOT set out to find a solution to effectively illuminate the roadway and provide the needed energy savings. Through research, it discovered only two fixtures could help achieve its goals.
The Solution with the Perfect Payback
The MaineDOT installed two different fixtures to compare the light quality and calculate the energy savings. After assessing the fixtures in the field, MaineDOT selected the Holophane® HMAO™ LED high mast from Acuity Brands®.
“We tested two types of fixtures from different manufacturers. Although both fixtures had excellent light quality, the HMAO LED high mast provided the quality lighting we were looking for, with the payback we needed,” said Cote.
The HMAO LED high mast fixtures use prismatic glass optics that provide an overlapping distribution from each LED module and minimize the direct view of the light source. This helps eliminate the potential for dark spots and reduces glare for visual comfort.
The new LED high mast solutions use significantly less wattage than the previous fixtures. The HMAO LED uses only 290-watts and has an expected life of 25 years. Furthermore, the LED fixtures include multiple light sources for backup lighting capabilities.
“Previously, if the lights went out, that was it! We did not have another backup light source,” said Cote. “Now, there are at least three LED drivers and seven LED modules per fixture, providing us with backups for proper illumination. For roadway applications, if a light goes out, it is difficult to get someone there to quickly replace it. The benefits of multiple LED drivers and modules, and the longevity of these fixtures are exactly what we wanted.”
The new LED fixtures enable MaineDOT to achieve a visually comfortable, energy-saving solution. Now, each lighting tower costs only $66 per month and can be illuminated throughout the night. “The quality of light combined with the payback of these fixtures is absolutely incredible,” said Cote. “We have only completed the lighting in one area and already see cost savings.”
The MaineDOT estimates after all 105 towers are upgraded with LED fixtures, the department will save $135,000 annually in energy. Additionally, it is estimated the MaineDOT will save approximately $1.35 million over a 10-year timeframe. A total of seven areas will benefit from the lighting upgrade, including Falmouth, Portland, Saco, Kittery, Waterville, Bangor and Medway rest areas.
With one section completed in Falmouth, the MaineDOT has already received feedback from some of the most frequent I-295 travelers. “We heard from truck drivers that they prefer the new light source as opposed to the previous lighting,” said Cote. “We are extremely satisfied with the new lighting upgrade. As a result of the low power consumption of the LEDs, we are now looking to install a LED sequence control lighting system in upstate Maine.”
Products Included In This Solution
HMAO LED Luminaire