Philips EnduraLED 48"T8 apparently 32% less efficient than mercury gas technology
Available in 11W 825lm and 22W 1650lm.. 40,000 hrs/85% maintenance(over how many hrs, I don't know)
Can't be used with shunted instant-start sockets. It's wired like a glow-starter type fluorescent lamp with a jumper in place of the glow starter. No idea why it needs a shunt going from one end to the other.
With the starting efficacy only being 75LPW and mean of only 64LPW, there is much to be desired when two lamp T8 can get 92new/90mean system LPW. Mean efficacy is 30% less than the modern T8 and that's simply unacceptable. Initial lumen is only good for the wow effect for sales demo.
3100new/2915 rated mean
2 lamps at 77% drive reduced output
AC 277v 48W
4490/48 = 93.5 sustained LPW, 99.5 LPW new
(2915mean lamp lumen x 2 lamps x 77% ballast output)=4490lm. 4490/48 watt input yields 93.5 lumens per watt.
LED 1400 lm mean (1650 x 85% maintenance)
4490lm/1400lm =3.21 lamps
so 1400 x 3 lamps = 4200 lm
6.5% reduction in output
22W x 3 = 66W 37.5% increase in power use.
32% reduction in efficacy
1400 mean lumen x 3 lamps = 4200 lm. 4200 / 66W lumen yields 63.4 lumens per watt.
63.4/93.5 = 0.678
(1-0.678) x 100 = 67.8... so, the LED setup is the 68% the efficiency of fluorescent system, which can also be stated as 32% less efficient.
Not sure what they're using in the sell sheet, but the above calculation is based on GE UltraMax-L 2 lamp and Philips F32T8/ADV835