H.R.117 – The Energy Efficiency Free Market Act of 2017 – introduced in Congress in January would prohibit the Dept. of Energy (DOE) from enforcing energy efficiency standards now on the books or setting new ones. If the Bill is enacted, one result will be making moot what seem to be misleading energy efficiency figures for TVs
Last fall, the environmental group Natural Resources Defense Council (NRDC) released research on power consumption that showed some TVs did better at DOE power dissipation tests than they were likely to do in real life. The offending manufacturers were LG, Samsung, and Vizio. NRDC said some TVs consumed twice as much energy as claimed in promotional material.
The problem, says NRDC, is that there are deficiencies in the DOE method for testing the energy use. In addition, TVs from the offending manufacturers were designed to disable key energy-saving features, often without adequate on-screen warning, whenever a user changes the default picture setting.
A TV’s energy use depends greatly on the picture settings selected, the screen brightness, and the
display content. The DOE measures energy use of new TVs when playing a 10-minute video of assorted content developed by the IEC standards organization which is meant to represent typical viewing. This testing takes place with the TV in its default settings. The results are used for getting EnergyStar designations and to determine the annual energy use listed on the yellow EnergyGuide labels now mandated by the Federal Trade Commission to appear on TVs sold in stores.
NRDC testing used the 10-minute IEC video specified by the DOE protocol. But the organization also tested the TVs using two alternatives to the DOE test loop video: real-world content NRDC created to reflect typical viewing, and UHD + HDR movies.
Some of the differences observed in power consumption relate to a motion-detection dimming (MDD) feature in Samsung and LG TVs, which dims or briefly turns off the screen’s backlight when the content on display has rapid motion and frequent scene changes, as is common in commercials and music videos. NRDC says the test clip developed by the IEC and used by the DOE contains much shorter scenes and more frequent cuts between them than typical real-world content from sports, dramas, and news programs.
While MDD caused on-mode power to drop by 58% in the DOE test on the LG TV, it dropped by only 13% when playing the real-world content video loop NRDC created. In a nutshell, the MDD feature saves more energy during the official government testing than it does when users view most programming that people typically watch, NRDC says. Therefore, NRDC thinks it’s conceivable that some manufacturers might have been exploiting the abnormally high frequency of scene changes in the IEC test clip to maximize the effect of MDD and obtain a better energy efficiency score. Both LG and Vizio have since denied wrongdoing, and Samsung has not commented on the NRDC findings.
The TVs tested from Samsung, LG, and Vizio also disabled key energy-saving features when the user changes the default picture setting (e.g., from Normal to Cinema, Sports, or Vivid) to modify the viewing experience. The disabled features could include MDD and automatic brightness control (ABC), which automatically adjusts the TV screen’s brightness and power level according to the amount of ambient light in the room.
Since the tests, LG updated its firmware so changes in display settings don’t disable energy saving features without warning. Meanwhile, the DoE is said to be looking into modernizing its TV power consumption tests, assuming H.R. 117 doesn’t eliminate them. And the EU, which uses similar tests, is said to be examining its procedures as well.
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