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Phase angle controlled heating results in extreme electric bills

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Skogsgurra

Electrical
Mar 31, 2003
11,815
About ten years ago, customers all over Sweden (and probably also in many other countries) noticed that their electric bills jumped sky-high after "intelligent meters" had been installed.

I did tests with three different brands of meters plus an old analog watt-meter (Norma class .5) and also by recording voltages and currents in an Excel sheet. Leaving out most of the details, a snippet of the results is shown below.

image_c4kshk.png


This investigation resulted in customers getting a compensation and meters were changed to other makes.

But he percentage that actually protested was low (most installations didn't use phase-controlled "dimming" of their power loads) and the whole thing was silenced down by the authorities.

The meter make was quite common and probably used all over the world.


Question: Have you experienced a similar problem with meters that do not "understand" how power is measured (my suspicion is that they just used voltage and current and multiplied by cos(phi) instead of summing instantaneous energy packets).

If you have experienced the same thing: How was it handled by utilities and law?

Gunnar Englund
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Half full - Half empty? I don't mind. It's what in it that counts.
 
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Gees Gunnar, this is a sore spot for me. My bill will be $75 one month and (this month) $523. Next month it will likely be $75 again. Extremely aggravating. I don't have a smart meter but every single person I know stated categorically that their bills went up the very next billing cycle and never came down.



Typically organizations use new technology that is more accurate to then adjust the readings right up to the legal allowed historical high error span. So if the meter can be + or - 3% they'll use the new accuracy as a tool to allow them to set every last meter to +2.9%.

On those crazy meters of yours I suspect they are simply taking snap shots of the instantaneous power and then averaging it over some long period like a second or 5 seconds. If the reading A2D snapshot is at the peak of a phase-angle pulse it raises the average - dramatically. To keep power consumption really low on the revenue monitoring they probably don't do continuous 1us readings to give a fine, high quality integration. Cheapskates.



BTW: Pacific Graft & Extortion charged me $100 for electrical energy and $250 to deliver it. I'm seriously considering going pseudo-off-grid.

Keith Cress
kcress -
 
Years ago I had a bad meter on my house. I phoned the utility to report it. They weren't very nice. Told me that there was a charge for checking meters. If they found that the meter was bad, then the charge would be refunded, otherwise I had to pay.
Well, no thanks. I guess that it may not be that bad. I can live with it.
Well, I tried.
The potential coil in the meter was faulty.
The meter never turned.
I was billed the minimum each month with zero consumption.
I felt that I had fulfilled my ethical obligation to report a faulty meter.
My ethics didn't extend to paying to have it fixed.

I remember that thread Gunnar.
The closest that I came was an electronic meter that was bad (not a program glitch). The utility replaced the meter and made a very reasonable adjustment in regards to the overcharges.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Please give meter make that you're talking about.

Lot's of controversies over 'smart' meters or 'intelligent' meters.

PG&E in california got busted after they installed almost $3B worth of 'smart' meters to only get sued for over-billing. Part of me wonders if this is the new normal.
 
Your mechanical meter with its disk-motor was being driven I imagine only by the 60 hz component. I think it would be better if the 60 hz component was used. I am guess that varies less than instantaneous sampling.

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If you can't explain it to a six year old, you don't understand it yourself.
 
Anecdotally there are too many complaints about smart meters causing massive lurches in energy bills to count. Most utility people attribute it to the previous meters having UNDER reported the real power use and the “smart meters” are now MORE accurate. I have tried to find a way to justify that stance (other than economically protecting their investment) and cannot. My suspicion has always been that non-linear loads are the culprits, because compared to 20 years ago, virtually EVERYTHING we use is now non-linear. CFL and LED lighting, power supplies for computers, chargers, TVs, “smart” appliances, energy efficient washers and driers not have little VFDs and as you point out resistive heating, that last bastion of linear loads, is being rendered as non-linear by virtue of the controller. You may be onto something here Gunnar.


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
 
I believe there should be a clause in most electric rate structures about non-linear loads.
Just the same there is a clause about poor power factor, and unbalanced three phase loading on business customers.

Same issue as years ago with flashing VCR's. Customers buy cheap equipment, and complain about the electric company.

Several years ago, we had a customer that wanted us to take power from his DC generator. We said NO, our standard is 60Hz AC.

Maybe you guys should join the analog world.
 
Bill that happened to me! My better half kept telling me our power bill was way too low. I shrugged. The next month she told me it was zero. I shrugged with raised eyebrows. The next month she said it was -$70. I shrugged with raised eyebrows, and added, "wow, that is odd".

I rationalized that it was PG&E, they'd realized they'd been ripping us off with the $75/$500/$75/$500 they'd been serving up for a year. The next month it was zero again. My wife worried that something was wrong and they'd come back and say we owed them $5,000 in back charges freaking our budget out. She came in the house and informed me the meter wasn't turning. I went out and looked at it. Sure enough, dead stopped. Had her turn on a 1440W heater - no change dead stopped. Same ethics dilemma Bill, I called them and said, "I think your meter is dead". They acted like I was a three headed troll without a brain but to assuage my concerns someone would be by to check it in a week and a half.

Guy shows up and asks me why I think my meter is bad. I told him it never spins. He stared at it for a minute and I told him, "hang on I'll turn the stove top on". That did it. He agreed it was dead. Pulled it and replaced it in about 3 minutes. He told me I should never have called. He said they'd figure it out but it takes 6 months for them to figure it out and they can't back charge you a nickle because it's their equipment that's to blame.

Dang.

A second huge downside came with this new analog non-smart meter. It cannot be driven backwards like the failed one could. This one simply stops. it can not go backwards. I suspect all new analog meters have sprag clutches in them.
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My company moved into a new building once, slightly ahead of schedule because the old building landlord got a hot new tenant prospect and paid us to move. 6 months later it’s November and the shop is cold, so I get tasked with finding out why the gas shop heaters are not working. Simple enough; the pilot lights are all out, maybe never lit since we had moved in in summer. Struggled for probably too long trying to get them lit before deciding there was no gas. Walked around the building and where the gas meter was supposed to be was just pipes with caps. How did that happen? Because our gas and electric utility is the same, I looked into the electrical service room and there were the meter sockets with cardboard fillers; no meters either! Opened the can (no seals of course) and apparently the builder had put jumpers in the socket jaws, then nobody called PG&E. They DID back bill us for 6 months of estimated useage, it was a whopper of a bill. I guess maybe because it wasn’t their fault?


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
 
I am surprised that this doesn't get brought up to this PUC. It is effectively a rate hike if the way energy is measured isn't the same.

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If you can't explain it to a six year old, you don't understand it yourself.
 
Yeah, just try to explain harmonics and non-linear loads to a politician...


" We are all here on earth to help others; what on earth the others are here for I don't know." -- W. H. Auden
 
Smart Meter program is very controversial in the US.

Public Utility Commission (PUC) or the Board of Public Utilities in many states are facing the dilemma to authorize the smart meter program considering the unpopularity of those meters or restrict investment and job creation.
Although the many public complaints, PUC/BPUs are authorizing the deployment of Smart Meter projects promoting to implement capital investment on system modernization including "Smart Grid" programs.

A typical survey data is showing below:
1) Changing in Utility Bill: Decrease (2.3%), same(25%), Increase (35%), not opinion (37.9%).
2) Complains of Meter the performance : ~ 54% - 65% and 86%-87% unsatified with the action.
3) Customer preferences: Conventional analog meters (95%)

Smart_Utility_Meter_pcvpw0.jpg

 
ANSI C12.1 applies to digital and electromechanical watthour meters, and specifies accuracy near the fundamental. Measurable inaccuracy for non-linear loads is mentioned and claimed to be under 2% in most cases. This is a case where the standard is a minimum. I think it is far more likely the electromechanical meters are filtering the harmonics out and the digital ones are measuring more accurately.

Early "smart" meters used a sensor to count disk revolutions. These were most likely to under-read, since the sensor could miss a count once in a while. Now digital meters are used with communication capability that directly read the registers. The digital meters can be purchased with and without communication, so don't confuse "smart" with digital.

Are you ever not home when the power goes out? You might come home from vacation to find a warm freezer and a big mess. This no longer happens where I live, since the power company knows of an outage before the phone rings.
 
Accuracy, I don't think is the issue. The generating units in regulated areas have cost that they are scheduled to re-coop. The regulator sees how much capital investment they have, fuel cost, ect. and lets them set a rate. The accuracy of the meters doesn't matter because it is all relative. It only matter that the meters are precise. If everyone's meter was reading high, then the rate set by the PUC would be adjusted to take that into account. The old meters didn't take harmonics into account so the cost passed down to the customer would have that include in how the rate was calculated. It is no different than how system losses are paid for. With the new meters, it doesn't work the same because the cost that were factored into the rate are now getting paid again at the meter. If everyone had the same meter, I don't think this would be an issue.


Smart meters are not a dumb thing though. It has easily been shown that smart meters pay for themselves in not having to send out a meter reader. In addition, the ability to disconnect a non-payer is much less work. Smart meters are 100% legit. I have seen a utility that uses peoples smart meter data to try to find the best electrical package. It takes your exact electrical profile and passes it through the formulas that represent different electrical distributor packages. It is a little disconcerning that someone could know when I am home or not but if they parked outside of my house they would know that,too. I have reservation for a lot of smart projects but smart meters are a simple winner.

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If you can't explain it to a six year old, you don't understand it yourself.
 
In the US also smart meter should comply with UL 2735
As Stevenal say, ANSI C12 and also apply IEEE 2030.5 and IEC meter series for the accuracy and performance levels of electric meters;
and UL 2900 series for cybersecurity assessment.
Below is list of national and international standard for smart meters

Smart_Meter_Compliance_sgrkhv.jpg

 
HH,
When you describe how the costs of non-linear power get passed down under the old system, I see inequity. Those with linear loads subsidized those with more non-linear loads in the mix. It's not all relative if the loads differ. The other inequity was where those with newly calibrated meters got to subsidize those with older/slower meters.
 
Stevenal,

Would that mean it is theoretically possible for someone to lower their bill by connecting to the utility through an inverter/converter?
 
I think that the issue that Gunnar is concerned with is not accuracy reading harmonics but a software package that is incorrectly making assumptions based on an inappropriate sampling rate.
We are not talking about few percent error but meters grossly overcharging.
The errors that Gunnar has observed are orders of magnitude greater than would be caused by harmonics issues.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
Correct, Bill.

Either that. Or an assumption from the SW guys that they always have full cycle loads. Which is not the case when there's phase angle control involved.

Gunnar Englund
--------------------------------------
Half full - Half empty? I don't mind. It's what in it that counts.
 
Stevenal,

We are saying the same thing. If everyone had smart meters, everyone would be paying the same rate. The inequality now is against the people with new meters because they are paying for actual power including harmonics and the harmonics socialized on mechanical meters.

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If you can't explain it to a six year old, you don't understand it yourself.
 
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