Watt's Up, Doc?
To test this, I used a Watts Up power meter (shown in the photo above) and a series of six stationary test patterns on a special Samsung test disc (not commercially available). These patterns consisted of a series of alternating full black and 100% white bars, two different forms of color bars, and full-field black, gray, and white. The results here are the averages obtained from all these patterns. This should be reasonably representative of normal usewhatever that may be.
I also performed the same measurements on two previously reviewed sets that are still at our main video studio (a different location from where the Sharp and Pioneer are, which is why neither of them were included in the Sharp review's side-by-side comparisons)the Panasonic TC-P55VT30 plasma and the Sony XBR-55HX929 LED-backlit LCD. At 55 inches, both of these sets are slightly smaller than the Sharp and Pioneer.
The Sharp was first measured in its main review configurationlocal dimming on and Intelligent Variable Contrast off. The Sony also had its local dimming engaged. All of the sets were measured as calibrated to provide their best performance, with peak white brightness levels between 25 and 30 foot-lamberts. All the results here are to the nearest watt.
LED-backlit LCDs:
- Sharp Elite PRO-60X5FD: 54
- Sony XBR-55HX929: 57
Plasmas:
- Pioneer Elite PRO-141FD: 280
- Panasonic TC-P55VT30: 237
With a full black-field pattern (which is included in the above averages), the readings ranged from a high of 59W on the Pioneer to a low of 29W with the Sharp. The Sharp's average power draw increased with local dimming turned off, but only to 94W, while its black field reading, at 31W, barely budged.
The power consumption of the LCD sets tested here may be fairly typical of LCD, if those sets employ local dimming. But that won't necessarily be the case with all LCDs, particularly older or less expensive sets that still use fixed brightness fluorescent backlighting. In any event, it was an eye-opening exercise in just how much more power plasmas draw compared with LED-backlit LCDs.