There has been a great leap forward in LED technology over the past five years, and the brightness achievable from the best LED light sources has increased dramatically.
Increases in overall light output and improvements in efficiency mean that LED lighting is now more than a match for halogen in terms of light output, and almost twice as efficient.
LEDs offering 100 lumens per watt or more are available, giving 70 lumens per watt when installed in a good quality fixture. This matches the performance of fluorescent tubes, allowing for the inverter losses. The latest products from Citizen, for example, deliver 102 lumens per watt in the 350mA version, and the 1,500mA version in the same range can deliver 1,200 lumens output.
Power LEDs have been tracing a steep performance curve to deliver environmental and economic benefits in a growing variety of lighting. The most powerful LED light engines are now able to supersede conventional incandescent lamps for office lighting.
In a recent project with Canadian lighting specialist Burton Lighting Network, working with designer Therese Gould, 30 LED downlights were installed in the offices of Morguard Properties in Mississauga, Ontario as part of an upgrade and refurbishment.
The project replaced a mix of 90W and 120W PAR lamps.
Thanks to higher efficiency and lower operating voltages, LED light sources consume around one-third of the power for a comparable light output. Throughout a large office or an entire building, this translates into an appreciable saving in the number of watts consumed to light the premises.
Burton Lighting calculates a yearly power saving equivalent to around 1,600 Canadian dollars for the 30-lamp conversion at Morguard. Converting to LED lighting also unlocked some interesting additional energy savings due to the fact that less heat is produced, thereby reducing the load on the building air conditioning system.
The savings vary depending on the local climate, as this influences the air-conditioning time required; as a rule of thumb in the Ontario area, saving three watts of lighting power brings an additional one-watt saving in HVAC power.
In addition to delivering financial benefits, these energy savings help companies to demonstrate commitment to environmentally responsible behaviour.
See also: LED Luminaries, our new blog on LED lighting. LED industry insiders share their insights on the issues shaping the development of LED technology in general and LED lighting in particular.
Article written by Adrian Rawlinson, managing director at Marl International