Sony LCD exceeds Energy Star power draw 75% of time

Jan 29, 2009
For the last 16 years or so, the US government has maintained a program—dubbed Energy Star—designed to rate the electrical efficiency of products and pass that information on to the consumer. Today, any product with an Energy Star label is (theoretically) significantly more efficient than an "average" example of said product (or the set federal standard). Virtually anyone that manufacturers commercial electronics these days is interested in earning the right to label themselves as Energy Star-approved. Sony is no exception—a number of the company's many displays are Energy Star-compliant—but at least one of the company's LCD televisions has a problem.

Back in January, DeviceGuru received an e-mail from one Martin Hellman. Hellman wrote in to report an unusual problem with his Sony KDL-37XBR6 LCD television. This display is labeled as Energy Star compliant and, according to the included documentation, should draw just 0.1W at the wall while in standby mode (Hellman spoke to Sony on this point; the company confirmed the specification). Hellman confirmed that the television's power consumption did drop to a fraction of one watt or even 0, but reported that "about 75 percent of the time it is drawing about 20 watts." (Hellman doesn't state which meter he used or if it could record and average power consumption over a set period of time.)

Hellman eventually figured out that the problem was caused by the television's TV Guide update software. Every time the TV Guide software package decided to update itself, it enters what's referred to as "Download Acquisition Mode." The Bravia television then updates itself and returns to sleep mode. While in DAM, the TV is allowed to consume as much power as it wants—current Energy Star guidelines do not cover it.

The existence of the DAM loophole may explain why the TV draws 20W while updating the TV Guide, but not why the software has this particular Bravia spending 45 minutes of every hour off in update mode. There's no official documentation on how to turn the TV Guide update program off included with the LCD television, but Hellman managed to assemble (and post) a step-by-step guide to shutting down the feature.

At this point it sounds as though the problem has as much to do with TV Guide's software as it does with Sony, but both Energy Star and the Environmental Protection Agency (EPA) were less than thrilled to discover the issue. There's no information yet about how many televisions are affected or whether the same shut-down sequence can be used to disable the TV Guide on all systems. More worrisome is the possibility that the Bravia is representative of any number of Sony televisions.

While this may not be a major issue, it's a problem that highlights the difficulty of ensuring that a product is actually living up to its labeled efficiency. If the Energy Star program doesn't move quickly to close loopholes like DAM, the program could become little more than a rubber-stamp greenwasher for future product versions.

We don't know what the EPA's exact response to Sony's TV Guide problem will be, but a more detailed analysis of the problem is most definitely in order. How the EPA handles this situation will have an impact on its perceived authority to monitor and regulate energy efficiency standards.

This is a problem Sony should've found and fixed before the televisions hit the market—if a TV is spending 75 percent of its time in update mode consuming 20W, one expects someone on the testing floor should have noticed. Given the realities of updatable content, software bugs, and the fact that software from multiple vendors may be running on a single television, it's clear that Sony's responsibility to deliver low-power operation in accordance with a television's specifications does not stop at the factory loading dock.

Update: Electronics manufacturers have jumped on the "green" bandwagon in a major way these past 12 months. Companies are falling all over themselves to bring you the best in power-saving tech, but Sony has at least a small problem on its hands. One of the company's 37" LCDs does indeed draw just 1W in idle. Problem is, it only does it on occasion. Power draw for most of every hour sits at 20W, and the folks at Energy Star aren't happy about it.