DOE Case Study & Analysis - Post Top Decorative Pole Lighting
Decorative Post Top Lamps are prevalent outdoor lighting fixture for walkways, parks, driveways, streets, campuses, or historic district lighting. The Department of Energy (DOE), through its Gateway Solid-state Lighting Technology Program has published a report on upgrading to LED Post Top fixtures in NYC’s Central Park.
DOE evaluated five different LED Post Top Fixtures and used a 175 watt metal halide (MH) post top lamp for the baseline comparisons. Their analysis showed a lifetime savings ranging from $2,258 to $4,688 / fixture for the various outdoor lighting products. Energy savings were from 51% to 81% for the SSL luminaires.
LED Post Tops Effective in Illumination
The Post Top LED fixtures used light more effectively in both vertical illumination, important for face recognition and security, as well as in lighting the ground. The DOE report also noted: “The LED luminaires tend to have higher light levels at greater horizontal distances corresponding to a wider distribution.” DOE also reported that after accounting for un-needed up-light and fixture losses, the initial 14,480 lumens of the metal halide lamp translates into 6,800 lumens delivered downwards for illumination. The report cites that the LED Post Top Decorative Lamps produced 95% or more downward lumens.
LED Retrofit Kits – Quantified Maintenance Savings
The demonstration also quantified maintenance cost savings for the LED Post Tops, showing further savings. “Total estimated maintenance costs for the approximately 1,600 luminaires in Central Park are reported to be $178,560 per year, or about $111.60 per luminaire per year. According to NYCDOT, this value breaks down into roughly $65.60 for pole/fixture/ballast maintenance and $46.00 for lamp replacement.”
In comparison to the lighting fixtures analyzed by DOE in Central Park, Metro LED Lighting fixtures offer an effective, if not better, directed light, and the light lamp engines, are fully adaptable to many historic light poles, acorn globes, or historic lantern style pole lamps. The Post Top Retrofit Kits are available in lumen outputs of between 3,000 lm and 6,500 lm, providing effective replacements for 100 watt to 250 watt, metal halide (MH) post tops, or high pressure sodium (HPS) units. Further, our Post Top Retrofit Kits are more economical than those demonstrated in Central Park, which will result in faster paybacks, and a better ROI. Additionally, the Post Top Lamp Replacement Kit is eligible for DLC rebate programs, further reducing costs.
LED Post Tops Provide Effective Pathway Lighting
The DOE report shows that effect pathway illumination can be achieved with LED Post Top Lighting. Further, significant savings in electrical costs and maintenance are to be realized. “The products appear similar enough to the baseline that will not alter the aesthetic of Central Park.”
Thus, as the Gateway report shows, retrofitting Post Top Decorative Pole Lamps with LEDs saves significant costs, while maintaining a high quality of lighting this outdoor lighting application.