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Millions of Smart Meters May Over-Inflate Readings by up to 600% (bleepingcomputer.com)
"Lab tests carried out by Dutch scientists have shown that some of today's 'smart' electrical meters may give out false readings that in some cases can be 582% higher than actual energy consumption," reports BleepingComputer. An anonymous reader quotes their report:
The study involved several tests conducted on nine different brands of "smart" meters, also referred to in the industry as "static energy meters." Researchers also used one electromechanical meter for reference... Experiments went on for six months, with individual tests lasting at least one week, and sometimes several weeks. Test results varied wildly, with some meters reporting errors way above their disclosed range, going from -32% to +582%...
The results of the study also matched numbers posted on an online forum by a disgruntled Dutchman complaining about high energy bills... Researchers blamed all the issues on the design of some smart meters, and, ironically, electrical devices with energy-saving features. The latter devices, researchers say, introduced a large amount of noise in electrical current waveforms, which disrupt the smart meter sensors tasked with recording power consumption...
Long-time Slashdot reader ClarkMills points out the researchers estimate that "potentially inaccurate meters have been installed in the meter cabinets of at least 750,000 Dutch households," while the article suggests that worldwide, "the numbers of possibly faulty smart meters could be in the millions,especially after some governments, especially in the EU, have pushed for smart meters to replace classic electromechanical (rotating disk) meters."
The results of the study also matched numbers posted on an online forum by a disgruntled Dutchman complaining about high energy bills... Researchers blamed all the issues on the design of some smart meters, and, ironically, electrical devices with energy-saving features. The latter devices, researchers say, introduced a large amount of noise in electrical current waveforms, which disrupt the smart meter sensors tasked with recording power consumption...
Long-time Slashdot reader ClarkMills points out the researchers estimate that "potentially inaccurate meters have been installed in the meter cabinets of at least 750,000 Dutch households," while the article suggests that worldwide, "the numbers of possibly faulty smart meters could be in the millions,especially after some governments, especially in the EU, have pushed for smart meters to replace classic electromechanical (rotating disk) meters."
56% measured power usage much greater than what was actually being used in a ridiculous corner case scenario involving a parallel string of identical low-quality LED lights with an absolutely dismal power factor, connected to a dimmer to make the power factor even more extreme. Read the actual article with the current waveforms. They looks like something a 2 year old scribbled on a piece of paper, not a sine wave.
Yes, there's a certification failure here (meters are not tested with non-sinusoidal current loads), but no, nobody's meter is actually measuring 6 times real power usage in reality. The moment you have any reasonable loads in parallel the current waveform will start being something more reasonably approximating a sine wave and the meter will read more accurately.
This is the actual list of tests from the article:
So no, unless your whole house consists of crappy LED and CFL lights behind a huge shared dimmer at a 135 degrees setting, and no other appliances, your meter isn't going to read 600% of real energy consumption. To even get 164% readings you still need everything behind a dimmer at 90 degrees.