Richard Lamb wrote:
Efficient Lighting

http://www.otherpower.com/otherpower_lighting.html

The article is correct about the efficiency of white LEDs. LEDs are not
going to illuminate homes and offices unless a breakthrogh in
efficiency occurs. All the claims in this regard is nothing but a
marketing hype.

But when it comes to a monochromatic source (red, green, etc..) the
LEDs easily outperform any other conventional source with a color
filter. This is one reason why they are popular in brake lights and
traffic lights. That is also the reason for its use a nav lights in
aircraft.