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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."
From the picture you can see their set up is flawed. The current sensor they are using can be inaccurate but more importantly they are likely measuring power as current*voltage which is only correct in AC for purely resistive loads. The switching power supplies in the LED light bulbs or the ballasts in florescent lights or any inductive motor will cause this reading to be incorrect.
I didn't recognize any of the meters in the pictures. The big makers L+G, Itron, Elster and Senses go through an insane amount of testing and regulatory oversight. These are almost commodity items and the cost of a recall would wipe out tens of years of profit.
We do need smart meters. We need to have billing based on the cost of electricity production so that we can use things like wind and solar. I want people to use more energy when the wind blows or the sun shines and I want to avoid building and firing up peaker plants.
Lastly ask some former meter readers from Texas and the US south how much they miss being bitten by dogs and shot at while reading meters.
she would have to bear the cost of around €900
A fair policy would be that she only bears the cost if the meter is accurate.
Also, it is not that hard to test your own meter. Turn everything off. Make sure the meter is reading zero watts. Then turn on one device at a time, and measure the power bump. Use a Kill-o-Watt or other plug-in meter to measure what the device is using at the wall socket. If there is really a 5 fold discrepancy, that should be really easy to verify.
You are incorrect.
Maybe this setup applies in some towns where the entire grid and all customers are served by a single company, I don't know. But in a competitive marketplace? No. Nuh-uh. No way. Nothing even remotely like this happens.
Every address is "tied" to a substation. This tie is purely nominal, because all the substations are feeding into the same grid, so saying that an address is served by a particular substation is never going to be more than a wild approximation anyway, and load will be shifted between them to balance out as required. Reconciling the household use to per-substation use is a herculean task that involves crunching billions of numbers per day, and still comes up with massive fudge factors.
Disclosure: I am the reconciliation manager for a small electricity retailer. A couple of times a month, I have to submit several megs of data to an authority called the Reconciliation Manager, who is responsible for billing us for the power used. The RM combines this data from all retailers (as I said, we're only a small one) and publishes the results in the form of our bill and various other reports, including several featuring "unaccounted-for electricity".
Way to miss the point.
The smart meter freaks out for no reason and charges you $500 extra. You complain to the utility, they say it's your fault. You complain to PUC, they ask you for proof. You have none. Congrats, you're now out $500.
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.
QA was probably done on linear loads which is where the meters would be accurate. On noisy switch mode loads (VSDs, computer power supplies, etc) there was probably minimal QA. Quite likely because regulation has not caught up with the prevalence of these loads. It is a case of meter manufacturers not keeping up with the time. And yes, I have seen this on a large scale; I ran into one power meter with a 200kW difference from the 1MW VSD it was down-stream of. And that was with some harmonic filters installed on the drive, yet the meter still read less than the drive. I'm inclined to suspect the meter here.
I have determined that my sig is indeterminate.
One name for an inductive ammeter of that sort, is Rogowski coil (which, according to the article, is a suspect).
The whole problem here is that the bandpass of the Rogowski coil is very high, but maybe the voltmeter isn't. The digital data capture and calculation are flawed. Some electronic power uses (like all the LED lights, and microwave ovens) are as high frequency as the meters can handle, and some are higher.
The study's main point, is that 'smart' meters were inadequately tested, and have flaws that got past the weights and measures inspectors. Those inspectors need better test methods; fortunately, the researchers just published some of those.