Sharp Corporation will introduce into the Japanese market two models of solar-powered LED street lights that combine Sharp’s proprietary solar (photovoltaic) modules and high-intensity, long-life white LEDs (light emitting diodes). The LN-LW3A1 Solar-Powered LED Street Light delivers brightness at the industry’s highest level (instrument-measured luminous flux: 1,800 lumens) rivaling the light output from a regular 32-W fluorescent security light (which uses six compact fluorescent tubes) that is becoming the dominant product for this application. The LN-LS2A1 (instrument-measured luminous flux: 1,200 lumens) provides light output comparable to the 20-W class of security lights and is ideal for spot lighting in areas such as public parks.

The light from the LN-LW3A1 is bright enough to enable a person to make out the general facial features of a pedestrian on a darkened street or walkway at night from up to four meters away, regarded as the minimum distance required to take evasive action after judging the other person to be suspicious (“Class A” recommended illumination level for security lighting when units are installed at 13-meter intervals*²). These units also feature a Seismic Motion Sensor that detects the occurrence of a major earthquake measuring 5 or greater on the Japanese seismic scale and turns on the unit at full brightness during nighttime hours for two days*³. This allows these units to serve as emergency lights in case of a power interruption in the surrounding area.

Expectations are increasing for solar-powered LED lighting to become the environmentally friendly outdoor lighting for the 21st century. These units generate no CO2 emissions and work by storing electricity generated by sunlight during the day in storage batteries to provide illumination at night.

The operation of the LN-LW3A1 eliminates approximately 48 kg of CO2 emissions per year compared to using lighting units powered by conventional utility sources*⁴. The integrated LEDs use no mercury, an environmentally hazardous substance, and also emit no ultraviolet light. Further, because they have a long service life requiring replacement only once every 10 years, almost no time and effort is involved in maintenance.

By meeting demand for new installations of street lights which is said to be 100,000 per year in Japan, Sharp is offering these units as powerful floodlights for crime deterrence and emergency safety lighting featuring both environmental performance and nighttime visibility.

1.		LN-LW3A1 offers brightness among the highest in the industry for solar-powered LED lighting with an instrument-measured luminous flux of 1,800 lumens, approximately six times higher than its predecessor*5.
2.		High environmental performance based on a solar power (PV) system and long-life LEDs that significantly reduce the use of environmentally hazardous substances.
3.		Seismic Motion Sensor detects large earthquakes (5 or greater on the Japanese seismic scale) and triggers full illumination during nighttime hours for two days.
4.		Highly expandable based on a flexible system design capable of accommodating a wide range of user needs.

Development Background
Expectations are increasing for solar-powered LED lighting to become the environmentally friendly outdoor lighting for the 21st century by using the natural energy contained in sunlight as the light source to power LEDs, which offer outstanding environmental performance and maintainability. Also, the fact that they have their own independent system for generating power means that they can be installed in places where running underground power lines would be difficult and can function as emergency lighting when utility power has failed, such as in the event of an earthquake. As a result, huge demand is anticipated in the future as the next generation of lighting that meets the three all-important criteria of being environmentally friendly plus offering safety and peace of mind.

Sharp introduced its first solar-power LED street light in October 2005, and they have since been installed in a variety of locations, including schools, parks, and commercial establishments. Now, high-intensity LEDs brighter than ever before and devising a new method of dispersing the light enables the LN-LW3A1 to achieve a brightness rivaling 32-W inverter fluorescent lamps, which continue to grow as the dominant product for outdoor crime-deterrence lighting applications, and the LN-LS2A1 to achieve a brightness comparable to 20-W fluorescent lamps, which are currently the mainstream for security lighting.

1.

Brightness among the highest in the industry for solar-powered LED lighting with an instrument-measured luminous flux of 1,800 lumens, approximately six times higher than its predecessor. (LN-LW3A1)

In addition to using high-intensity LEDs, the LN-LW3A1 offers improved light distribution characteristics based on a proprietary V-shaped lamp fixture design that is key to dispersing the light not only directly downward, but also to the right and left, and to the front of the light stand. In outdoor lighting whose light source is LEDs, the LN-LW3A1 is the first to have achieved an instrument-measured luminous flux of 1,800 lumens, roughly six times brighter than its predecessor and a brightness among the highest in the industry, and the “Class A” recommended illumination level for security lighting (illumination range: 5 m in front with units installed at 13-meter intervals).

In addition, a built-in controller*⁶ automatically turns on the light when darkness falls, and keeps it lit at full brightness for seven hours after sunset. The light then enters an energy conservation mode and remains lit for the remainder of the nighttime hours, thereby contributing to preventing street crime.

2.

High environmental performance based on a solar power (PV) system and long-life LEDs that significantly reduce the use of environmentally hazardous substances. (LN-LW3A1/LN-LS2A1)

Solar-powered LED lights are stand-alone lighting systems that generate electricity from the energy of sunlight during the day and supply that electricity to power lights at night. The LN-LW3A1 can reduce emissions of CO2, a cause of global warming, by approximately 48 kg per year*⁷. The LEDs used in the light-generating section have a service life of approximately 40,000 hours*⁸, and can be used for approximately 10 years before requiring replacement. In addition, they use no mercury, an environmentally hazardous substance.

3.

Seismic Motion Sensor detects large earthquakes (5 or greater on the Japanese seismic scale) and triggers full illumination during nighttime hours for two days. (LN-LW3A1/LN-LS2A1)

A seismic motion sensor built into the support pole of the main unit detects shaking (acceleration of 130 to 200 gals) greater than the equivalent of an earthquake measuring 5 on the Japanese seismic scale and automatically switches to full nighttime illumination mode*⁹ for two days*¹⁰.

4.

Main body is made of corrosion-resistant, lightweight aluminum alloy for easy installation. Plus, these units are highly expandable based on a flexible system design capable of accommodating a wide range of user needs. (LN-LW3A1/LN-LS2A1)

The main body is made of an aluminum alloy for light weight and easy, simple installation compared to steel pipe. In addition to an anodized aluminum finish, the surface is further protected with a matte paint coating for improved corrosion resistance. Also, a proprietary system design makes these units expandable to meet user needs, including color accent panels, map insert panels, and banner mounts (to display promotional flags, etc.).

5.

LED-based light tends not to attract insects, dramatically reducing the time and labor involved in cleaning and maintaining the attractive appearance of the units for extended periods of time. (LN-LW3A1/LN-LS2A1)

Insects have a behavior (phototaxis) in which they tend to congregate in the vicinity of light having a wavelength in the ultraviolet range of around 350 nm. Conventional lighting (fluorescent or incandescent lights) generates ultraviolet light in this wavelength range and insects readily congregate around these light sources. Because insects do not tend to congregate around solar-powered LED lighting which uses LEDs that generate no ultraviolet light, cleaning of lighting fixtures can be reduced, making it possible to maintain the attractive appearance of the units for extended periods of time.