Cree breaks 200 lm/W barrier, demos 208 lm/W in lab

Regarding the percentage of input power converted to light, it's probably around 63% light, 37% heat. The spectrum of a YAG phosphor LED is roughly 330 lumens per watt, so 208/330 = 0.63 = 63%. Cree may be fine tuning the phosphor a bit to get more light in the wavelengths which the eye is more sensitive to at the expense of color rendering, so conversion efficency might actually be a little less than my 63% figure. But in any case it's at least 60% light, 40% heat. I'll also add that due to Stokes losses phosphor white LEDs can never be 100% efficient. Even with a perfectly efficient blue emitter, you would still lose about 20% in the phosphor. White light made by combining red, green, and blue emitters on the other hand can be 100% efficient in theory.

A 'standard' 100 watt light bulb produces about 1700 lumens. 1700 divided by 200 is 8.5 watts. This is about like getting your compact car to get 360 miles per gallon.

At that level of efficiency, getting the heat out is almost a non-issue. My calculations show that about 90% of the power coming out is light so this 1W device only need dissipate ~100mW. Just like good switchers, hardly need a heatsink now.

That is simply AMAZING. Now, if someone could talk their manufacturing folks into building these on 6 or 8 inch wafers and speak to that Gordon Moore guy as to why they should do this when they are doing fine financially, we might actually have a viable industry and planet-responsible technology.