wrote:
LEDs do actually produce as much heat as the same wattage lightbulb.
Here's a link http://www.patmullins.com/ledlightmyths.html#toc2 that
describes the screw in bulb replacements as doomed to fail without
adequate heat dissipating area. I think the Lumileds design guides also
show that surface area to be about 9 square inches per watt.

The MCPCB that Lumileds stars are mounted on, 1 inch square , is rated
as minimum heatsink requirement for 1W in 25 C ambient, temp of star
board in 70`s C and junction temp at the limit.

Adam