Here is something I don't really get about the energy saving halogen bulbs. The Philips Halogena energy saver are rated at 3000 hours life. On the other hand the Sylvania super saver halogen are rated at 1000 hours. For comparison the Philips Halogen 70 watt produces 1600 lumens while the Sylvania 72 watt is 1490 lumens, both are advertised as 100 watt equivalents. How is the Philips bulb is able to achieve 3000 hours and at the same time have higher efficiency?

The Philips Halogena energy saver lamps utilize an infrared reflective coating, which boosts efficiency without reducing lamp life.  I believe most of the other halogen energy saving lamps simply employ a hotter-burning filament to increase efficiency.

Thanks, thats makes sense.

The Philips halogena energy saver bulbs don't seem to last long so I was never able to see if they last around 3000 hours. I used it in a floor lamp but a small bump to the lamp and it turns bright then burns out. Probably works better for ceiling lights. Too bad they are not easy to find, Home Depot was the only place I know of that used to have it but doesn't carry it anymore.

The Philips Halogena energy saver lamps utilize an infrared reflective coating, which boosts efficiency without reducing lamp life.  I believe most of the other halogen energy saving lamps simply employ a hotter-burning filament to increase efficiency.

Usually only 12V halogens, have an IRC (InfraRed Coating). Mains voltage halogens usually don't have this coating.

what about 400w linear halogen that replaces 500w version?

@dor123: The IRC is used, when the lamp shape allow the reflected rays to reach the filament.
That is the case for ball shaped short filament low voltage capsules, as well as tubular lamps in any length.
So if the lamp uses one of these formats, the IRC work well.
And for 120V the linear format does not have to be so long (230V is limited by EOL arcing), so could fit into the standard pearl shape outer.
For 230V I've seen IRC's only in the 78 or 115mm R7s format (from GE).