With new applications emerging every day, the lighting industry is realising that the unparalleled nature of LEDs makes them ideal for applications other than indicator and display devices. The following article outlines some of the dynamic aspects and applications of this innovative lighting technology.
A new light source
Lighting applications that use LEDs, organic LEDs (OLEDs), or light-emitting polymers are classified as solid-state lighting technology. Solid-state lighting, including LED technology, is positioned to revolutionise the entire lighting industry. The advancements in LED technology throughout its relatively short lifespan make it the most significant emergence of new lighting technology since the introduction of fluorescent lighting in the 1940s.
In terms of mass, LEDs are extremely small and consist of a silicon ‘chip’ approximately the size of a grain of salt, which is illuminated by the movement of electrons through semiconductor material. Essentially, LEDs are electronic devices that when electricity passes through, it lights up. Distinct from other luminaire types, LEDs offer several significant advantages over its grid-tie counterparts, including light quality, safety, durability, flexibility, and cost.
Advancing in a market primarily illuminated by electrical lighting does present certain challenges. While general illumination applications appear to be the ideal pr imary market for a revolutionary new light source, the market growth for ultra bright LEDs has been the result of utilisation in specialty applications, including marine aids to navigation. Proven to be very effective in applications where brightness, visibility and durability are vital, LEDs are also particularly suitable for solar power.
The efficiency of LEDs lowers maintenance costs, while its extreme durability more effectively withstands the elements and vandalism than conventional light sources. Playing to these strengths, and because they require coloured illumination, signalling beacons, navigational aids, and transportation applications are ideal industr ies to adopt this innovative technology. In particular, where coloured light is required, LEDs also have an even greater potential for reduced energy consumption.
Applying LED technology, Carmanah Technologies’ solarpowered LED lanterns, originally designed and built under contract with the US Coast Guard, represent the first LED technology to enter the US Navigational Aid System. One of the greatest advantages of LEDs for marine applications is that ‘lighter’ lights enable the use of smaller buoys. LEDs are one-tenth the weight of incandescent systems with an equivalent visibility range. The batteries alone for an incandescent light system might weigh 75 pounds (34 kg), whereas a typical self-contained LED with a three-mile range weighs just 11.5 pounds (5.21 kg). Measuring only 2-feet (0.6 m) long and at a fraction of the weight, plastic spar buoys are replacing large steel buoys, such as the Canadian Coast Guard’s (CCG) 9.5-foot (2.9 m) whistle buoy. Lighter buoys that can be serviced with smaller vessels also make it easier to outsource servicing to local businesses and individuals, contributing further to cost savings. While steel buoys must be hauled out for sandblasting and repainting at least every five or six years, plastic has a much longer maintenance interval and can be handled by much smaller ships and crews, resulting in significant installation and maintenance savings.
Exhibiting the robustness of Carmanah’s Solar LED marine lights is a rogue Canadian Coast Guard buoy that went adrift off the coast of Labrador in November 2003 and washed up more than a year later on the shores of Papa Stour in the Shetland Islands. The light was still flashing brightly despite its 5,800 km trek across the Atlantic Ocean. Operating on low-voltage DC current and generating a small amount of heat, LEDs can be completely self-contained, producing more durable and weathertight lights. Carmanah’s solar LED beacons are completely integrated and self-contained. Waterproof and extremely rugged, these lights are designed to operate flawlessly for up to 5 years maintenance free.
Carmanah’s solar LED marine lights have also proven to perform during extreme weather. Following Hurricane Charley that devastated Punta Gorda, Florida in August 2004, Carmanah’s beacons of light were the only visible light on the river in the aftermath of the devastating storm. Another testament to the robustness of Carmanah’s solar LED lights is revealed in the effort to rebuild the Gulf Coast following the ruinous Hurricane Katrina in fall 2005. The US Coast Guard ordered more than 500 of Carmanah’s solar-powered LED marine, railway and aviation lights to aid relief and rebuilding efforts.
Combining advanced solar technology with the efficiency of LEDs, Carmanah’s solar self-contained LEDs install anywhere in minutes and operate reliably for years without external electrical infrastructures. Carmanah’s solar LED marine lights are effectively used on fixed navigation aids worldwide, even in those locations where hydro connections are available and photovoltaics would not previously have been cost-effective. Savings on fixed aids come through reduced electricity expenses, rapid deployment, a potential six-year maintenance free cycle and the increased ability to contract out services.