INDUSTRIAL LIGHTING
Professor Zissis characterised the advantages of LEDs
as high luminance, excellent colour saturation, high
luminous efficacy, high energy conversion efficacy, small
dimensions and light weight, robustness, long lifespan,
low voltage power supply and ease of dimming.
However he went on to document some of the issues
and problems with the technology. These included:
• Eventual limits to efficacy of around 250 lumens per
Watt estimated to be reached in 2025;
• A marked difference between LED efficacy and system
efficacy arising from thermal management losses,
optical losses, ballast losses and photometry losses;
• Marked variations between claimed and tested
performance;
• Falsification by some vendors of test certificates;
• A multiplicity of conflicting standards;
• Issues with power supplies which include poor
manual soldering, unreliable wiring, low quality
components, low quality chemical capacitors, hot
points and low mechanical quality;
• Power factor and cost issues;
Bryan D