Since the 1990s cities at the U.S. and Europe started replacing incandescent-based traffic lights using high energy-efficient solid state lights, LED was taking to roads. At that point LED isn’t strong enough to be utilized in road lighting. In the last time, the technology of LED progressed. Today a growing number of street lighting jobs choose LED sources. It required the marketplace of high pressure sodium and mercury vapor slowly.

Why LED?

1) High Energy Efficiency. Now the energy efficiency of LED is over 100lm/w. In nearly all of street lighting job, the energy efficiency of LED is 65-80lm/w. It’s considerably higher than 30lm/w from mercury vapor lamps. 2) Eco-friendly. LED lighting is solid state lighting. 3) Extended Lifetime. The life of LED is 50,000 – 100,000 hours.

Philips utilized its LUXEON Rebel LED to check. LUXEON Rebel LED stacks up against both prominent lighting technologies High Pressure Sodium and Mercury Vapor utilized for road lighting. The outcomes are as follow:

LUXEON Rebel High Pressure Sodium Mercury Vapor Flux (lm) 3325 5510 4340 Power consumption 67W 90W 138W Method Efficacy (lm/W) 50 61 31 Typical Lux 14 19 14 Use 0.0042 0.0034 0.0032 Lux/W 0.21 0.21 0.10 Min/avg Lux Ratio 0.40 0.32 0.23 Lifetime (hours) 60,000 20,000 -30,000 6,000 – 10,000 From the above data, we could get these outcomes.

1). Reduced power consumption – LED street lights (67W) conserve energy usage by 52 percent over Mercury Vapor lamps (138W) and 26 percent on a high pressure sodium lamps (90W)

2). Greater power efficiency – LED street lights transcend mercury vapor’s 31 lm/W. You may find increased efficiency measurement from for high pressure sodium lamps. It’s merely misleading since it comprises wasted light that subsequently exerts energy. On this website, much electricity efficiency of LED street lights may reach around 80lm/w.