We have seen roads illuminated by traditional sodium lamps, which depend on high energy consumption. Now, we can achieve superior illumination from LED street lights placed along the sides of a roadway or in the center of a divided highway. This system of electrical lighting utilizes highly efficient diodes for vehicles traveling on roadways. Operating at high efficiency, LEDs dispel darkness as we travel, providing clear visibility. By placing LED lights along roadsides or in their centers, safety can be maximized.
Why Highways Need LED Street Lights
There are more than a million miles of dark highways, which generate safety hazards. The same lighting that is responsible for huge municipal energy bills can be replaced with highly efficient LED street lights that use advanced diodes to illuminate passing cars on the highway.
How LED Street Lights Work
Natural moonlight normally does not exceed a few lumens per hour. Commercial adoption of a safe highway lighting system requires a large-scale illumination standard. Using advanced roadside LED lights, visibility can be achieved through bright beams aimed at high-speed moving vehicles.
A center-of-the-road LED fixture can project light drafts in opposite directions on each side of the road. The road center light pole has two optical lenses, one for each side of the road. Each lens has an LED array, a heat sink, and a protective cover. The first array faces in the opposite direction to roadway traffic. The second array faces toward the direction of roadway traffic on its side. The protective cover allows LED light beams to travel through this fixture with clear visibility.
A roadside LED street light is similar to the road center apparatus, except that it faces only one side of traffic, has only one optical lens, and has only one set of LED arrays and protective covers.
Benefits of LED Street Lights
Modern engineers designed overhead highway lights powered by efficient drivers. The diodes are illuminated by the electricity conducted as cars and trucks travel past at high speed at night.
This concept uses minimal electrical current to do useful work, such as generating brightness to illuminate highway lanes at night, while saving massive amounts of energy during operating hours.
City planner Michael Johnson implemented a massive LED upgrade for use along the roadside. His municipality, Highland County, moved from outdated sodium lamps to modern infrastructure under the government body’s global efficiency program, the Department of Transportation (DOT). The local government is investing in cleaner-energy technologies, and, given the strong year-round need for safety, this made Highland a good location for Johnson’s initiative.
Johnson’s light fixture sits 30’ tall and is made of recyclable aluminum housing. The fixture weighs just 15 pounds, which makes it easy to transport and install. The highly efficient driver can use a fraction of the electricity, enough to power two lamps and a sensor for around 50,000 hours. The idea is that this lighting could provide visibility for rural communities in developing countries or illuminate traffic lanes or road signs in urban areas.
Highways in the country offer long, uncontrolled stretches of dark roadways. The design of an LED street light must include heat management and a system to distribute the generated light effectively. LED lights are commonly used in remote locations, which adds the challenge of transporting the fixtures to the site.
Since the LED street lights are so close to traffic, the design must consider safety. The safety measures should include sturdy highway poles supporting the heavy fixture housing and warning signs. A traffic flow survey also needs to be conducted to establish boundary limits for the LED lighting design. There will be times when the weather will be foggy, stormy, and dark. During these times, the LED street light must be able to pierce through.
Future Trends in LED Lighting
Although most LED street lights are used in urban areas, there needs to be a fixture designed for use on rural highways to address the number of accidents caused by poor visibility and to introduce a potential source of safe travel.
Europe designed smart LEDs, which were very inexpensive, and the modular sections could easily be snapped together to form a larger system. That design was not as environmentally friendly as the designs with solar panels. Other designs include lights built into highway dividers or on overhead poles, as seen in the design by an Arizona State Student. He calculated that with LEDs operating at 100 watts, 9,600 kilowatts of electricity could be saved per year using this design.
The LED street lights shown are cool-running. In many developed areas, traffic volume is sufficient to maintain a steady demand for illumination throughout much of the night.
One of the best designs is a solar-powered LED light placed along roadways with high volumes of fast-moving traffic. The electricity needed will then be stored in batteries, and since the electricity produced will be direct current, it must be regulated by controllers so that it can be used for lighting the street lamps or disconnected from the grid. The DC current must pass through a driver before it can be used.
A solar-powered LED design is suitable because adjustable panels are effective at capturing sunlight from any direction, whereas traditional lights require grid power. In addition, heavy parts such as the controller and battery can be easily stored at the base of the light pole.
To sum up, extensive data needs to be collected on the light patterns required by vehicles on both sides of a highway. Using the collected data, an LED street light needs to be designed for placement on the highway medians. One light may not provide sufficient illumination, but a group of LEDs along a long stretch of highway has the potential to generate significant safety benefits that can be used to protect drivers, other public services, or even produce savings by reducing the power taken from the grid.
This design concept is workable and environmentally friendly. An LED street light powered by modern technology has many applications. Hypothetically, any dark roadway can use LED lighting, such as an amusement park path. A highway LED street light can enhance safety in any city around the world with high vehicle traffic.
