Solid State Lighting - LED
Today, we are facing the urgent challenges of revitalizing our economy, strengthening our energy security, and reducing greenhouse gas emissions. LED lighting is an emerging technology with the potential to address all three of these challenges.
Solid-state lighting will mean greener homes and businesses that use substantially less electricity, making them less dependent on fossil fuels. In the coming decade, they will become a key to affordable net-zero energy buildings that produce at least as much energy annually as they use from the grid.
Solid-state lighting has the potential to reduce lighting energy use significantly. With the promise of being more than ten times as efficient as incandescent lighting, light-emitting diodes (LEDs) and organic light-emitting diodes (OLEDs) will change the way we light our homes and businesses. Consumers will benefit from the superior features of solid state lighting (SSL) products.
By 2030, solid-state lighting could potentially reduce lighting electricity use by one-fourth.
Below are some unique LED characteristics:
• Directional light emission - directing light where it is needed.
• Size advantage - can be very compact and low-profile.
• Breakage resistance - no breakable glass or filaments.
• Cold temperature operation - performance improves in the cold.
• Instant on - require no warm up time.
• Rapid cycling capability - lifetime not affected by frequent switching.
• Controllability - compatible with electronic controls to change light levels and color characteristics.
• No IR or UV emissions - LEDs intended for lighting do not emit infrared or ultraviolet radiation.
LED Application Efficiency
Luminous efficacy is an important indicator of energy efficiency, but it doesn't tell the whole story, particularly with regards to directional light sources.
Due to the directional nature of their light emission, LEDs potentially have higher application efficiency than other light sources in certain lighting applications. Fluorescent and standard bulb shaped incandescent lamps emit light in all directions. Much of the light produced by the lamp is lost within the fixture, reabsorbed by the lamp, or escapes from the fixture in a direction that is not useful for the intended application. For many fixture types, including recessed downlights, troffers, and under-cabinet fixtures, it is not uncommon for 40-50% of the total light output of the lamp(s) to be lost before it exits the fixture.
LEDs emit light in a specific direction, reducing the need for reflectors and diffusers that can trap light, so well-designed fixtures can deliver light more efficiently to the intended location.