An LED lamp (or LED light bulb) is a solid-state lamp that uses light-emitting diodes(LEDs) as the source of light. LED lamps offer long service life and high energy efficiency, but initial costs are higher than those of fluorescent and incandescent lamps.
WHAT ARE LEDS?
LED stands for Light emitting Diode. LED have been around for many years with their first commercial usage in items like calculators back in 1978. An LED lamp (or LED light bulb) is a solid-state lamp that uses light-emitting diodes(LEDs) as the source of light. LED lamps offer long service life and high energy efficiency, but initial costs are higher than those of fluorescent and incandescent lamps. The efficiency of LED devices continues to improve, with some chips able to emit more than 100 lumens per watt.
LED Light application
LED Light technology have now moved on significantly in recent years. Now small clusters of 3 or 4 high power led’s can be used for replacement light bulbs with equivalent brightness but using 90% less electricity.
Over the last 10 to 15 years there has been a fashion trend within properties to have many recessed style ceiling lights but people often don’t realise the impact on their electricity bill. For example a domestic kitchen/ dining room in a modern house could have 15-20 halogen light each rated at 35-50 watts per bulb. So instead of the old 60w light bulb, the modern kitchen would have 750 watts of lighting. Replace all these lights with LED’s lights with efficiencies of up to 100 lumens per watt, the 750 watts consumption suddenly can be reduced back to 60 watts powering 15 lights and keeping the modern lighting style. Potential for energy savings in commercial property are far greater.
In 2008 Sentry Equipment Corporation in Oconomowoc, Wisconsin, USA, was able to light its new factory interior and exterior almost solely with LEDs. Initial cost was three times more than a traditional mix of incandescent and fluorescent lamps, but the extra cost will be repaid within two years via electricity savings, and the lamps should not need replacing for 20 years (NYT July 28th 2008)
LED LIGHT TECHNOLOGY
LED Lights do naturally cost more that traditional lighting. This is due to the new LED Light technology which costs more than traditional lights but is quickly repaid in electricity savings. LED Lights are now at the stage where they can offer great value due to their low electricity usage long life expectancy. The efficiency of LED devices continues to improve, with some chips able to emit more than 100 lumens per watt. Most LED lights now available are in excess of 95 lumens per watt efficiency. It is predicted that LED light technology could dominate the lighting market by 2015.
Types of LED lights
LED spotlight, LED ceiling light, LED flood light, LED corn light, LED light bulb, LED Tube light, LED panel light, LED Streetlights.
LED LIGHT COLOUR OPTIONS
LED lights colours are specified based on Kelvin colour scale temperature. Common colours are typically in warm white (3000-3500K), white (4000-4500K), and day white/ cool white (6000-6500K)
The Kelvin Colour Temperature Scale
LED Light Considerations and Advice
- The design of LED Lighting is important to ensure the they do not overheat as this significantly reduced their life. Reputable LED Lighting manufacturers are fully aware of this and must ensure that ventilation slots or metal heat sinks are utilised in the lamp design
- Many dimmable LED lights currently available can only be used with an LED compatible dimmer switch.
- Avoid very cheap LED lights are there are likely to have a poor color rendering index (CRI) due to low quality LEDs. CRI measures a light source’s ability to render colors, with 100 being the maximum. LEDs lights with CRI below 75 are not recommended use in indoor lighting.
LED LIGHT LIFETIME COST COMPARISONS WITH TRADITIONAL LIGHTING
|Cost Comparisons||Incandescent||Halogen||CFL compact Fluorescent||LED Light (Generic)||LED Light (Branded)|
|Electricity usage||60 W||42 W||13 W||5 W||5 W|
|Colour Temperature Kelvin||2700||3100||2700||3000||3000|
|Colour Rendering Index||100||100||82||>75||>75|
|Bulb replacement cost over 10 years – @6hours/day||£16.43 11 bulbs in 10 years||£18.55 7 bulbs in 10 years||£5.85 3 bulbs in 10 years||£0.00 no repl in 10 years||£0.00 no repl in 10 years|
|Energy cost over 10 years – @13p/kWhr||£170.80||£119.60||£37.00||£14.20||£14.20|
|Energy Saving Investment Payback Time||N/A||N/A||3 Months||7 Months||1 Year|