Mains electricity: undervoltage and overvoltage

Home Improvement
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Comments on the ABC News Report.
I have emailed the ABC with similar comments on the report, which appears to lack balance. Many of the relevant facts are poorly presented while some of the information could have been critically challenged but was not.

The report raises some significant issues including the relationship between grid voltages and solar panel feedin impacts. It also provides informed opinion by two experts in addition to Mr McIndoe.

A principle premise of the report opens with advice from Mr McIndoe that he has determined he is paying $1,200 per year for his electricity because of electricity supplied at the upper voltage limit permitted.

“I’m being force-fed more electricity than I need,” he said.
"Based on the 254 volts I’m getting here, I’m roughly paying about $1,200 more for my electricity each year than I need to.“

A further comment is that this is deliberate to increase the power used by consumers.

A final point re Mr McIndoe is:

After he realised the scale of the problem he started a company that specialises in filtering out extra voltage in homes and businesses.

As a retired professional I see the prospect of ‘snake oils’ here praying on fears based on incomplete facts or half truths. The technical arguments about increased power consumption due to higher voltage are complex. Some appliances or items will use the same power as voltage changes, some will use a little more - perhaps 1 or 2%. This is not $1,200 when typical homes use between $1,500 and $3,500 of electricity per year.

The technology possibly behind Mr McIndoe’s business and needed to change (filter?) voltage is expensive or simply will consume the excess as heat. The follow up interviews by the ABC did not challenge the proposition. The ABC did not explain how the voltage reduction would be achieved. Critically until very recently the legally standard for voltage in Qld Australia was 240v +/- 6% or a maximum of 254.8v. Recently as of Oct 2018 Qld is in a transition to a 230v nominal voltage. This does not support any argument current supply voltage levels are in any way a rort or costing a thousand dollars in extra power usage.

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I am always wary of those selling the solution to a problem that they could well have constructed. The product may be useful - maybe not.

BTW what are you a retired professional of? I ask because Choice publishes ‘expert advice’, I am wondering if you qualify in this case.

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As I commented to my wife regarding that segment on TV, his usual bill must be tens of thousands of dollars!

Many switch mode power supplies found in modern electronic equipment are designed to operate on a wide voltage range, often up to 265V. A grid voltage 10% higher than nominal will not generally affect power consumption for these devices. It will increase power consumption on purely resistive loads such as bar heaters, incandescent light bulbs etc, but I suspect that “$1200 more” is a huge exaggeration.

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It’s an interesting observation. I prefer to be more ordinary, however this instance of poor reporting fired me up.

There is a legal argument that if you are no longer in a registered profession you are no longer entitled to offer any advice on that basis. You should remain silent so as to not mislead or misrepresent. I have stepped out a little to avoid a more complex discussion on the physics of electrical equipment and machines. I have a broad background in Engineering should suffice for now.

In the instance of this particular news report the ABC is hanging it’s position on the views of an individual who may or may not have any technical expertise. That Mr McIndoe held a senior management role in an energy retailer suggests one answer but leaves it open to what expertise he may have? It may well be in accounting or law or marketing or even electrical power.

What is missing in the report despite some alternate reliable information and facts is a direct critic of the propositions.

IE

  • that higher supply voltages are deliberate at the hands of retailers,
  • secondly that higher voltages cause significant increases in measured household power usage (cost)
  • and the higher voltages are somehow abnormal, resulting in a sudden change to our power bills.

It is possible to argue some household devices draw less current at higher voltages due to their design and there is no power difference, eg LED lighting.

Other devices draw more current at higher voltages providing more power but subsequently need to operate for shorter times as a result and there is no power difference, eg kettle boiling water.

For electrical machines such as motors in appliances which are all highly efficient the majority of the electrical energy is output as mechanical energy into a load and there may only be a very small increase in power due to copper or magnetising losses, eg fridge compressor, washing machine.

The now oboselete incandescent light bulbs are a simple exception. Even then a supply voltage of 252v is only 5% above the nominal rated voltage for the design and approx 11% increase in power usage.

Higher supply voltages can stress items more, however based on Qld alone it has had 240v as standard up to Oct 2017.

With few exceptions all items for Australia have been designed and rated and tested for 240v plus a large margin for supply variation. The agreement to fully phase in the new 230v standard (previously 240v) by 2020 does not make all existing appliances power robbers. In reality most appliances will draw more current at the lower standard and use the same amount of power as they did one year prior. Old style light bulbs may be excepted, although concisely they too are not a constant value resistive load.

The most factual aspect of the report relates to the issues around solar PV system operation. This is a genuine concern. The state Govt regulators and retailers recognise this. It also deserves a lengthy technical and regulatory discussion, but it is way outside my current knowledge.

There is a risk that if the current initiatives by State Govts and the supply regulators are not sufficient there will be a move to regulate PV feedin by household based systems. IE the regulators will move to turn them off at peak times to limit voltage rise. The counter to this is with all the recent demands re increased spending on the distribution network to manage the changes in energy flows so that does not become necessary.

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Is this the same Richard McIndoe who has an education portfolio that looks like “Master of Arts (M.A.) Modern History” and “Master of Business Administration (MBA)” ? the same one who’s resume seems to indicate ‘career manager/director/etc’ ?

I love history - not so much a fan of MBA - and he might be a brilliant guy in his chosen field, but if I were wanting expert advice on power, I’d probably be keen to see something more aligned with engineering on the resume 
 and perhaps a year or 15 in a relevant field a little further away from board rooms, golf courses and boozy business lunches 
 oh, sorry, I already said he had an MBA 
 :wink:

Is that the waft of the easterly part of a westerly facing bovine my nose detects?

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This is already happening with large scale wind and PV generation, although not strictly for the same reason, see:

With new domestic inverters now all being Demand Response Enabling Devices, (DRED) electricity providers will be able to control these inverters too.

Get your batteries installed now and maintain control of your energy production! :wink:

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I saw the report and the information about increased bill seemed to be theories rather than based on proven facts.

The ABC also sensationalised the voltage measurements saying that all the readings were in the upper range of the upper voltage limits, suggesting that there was overvoltage all the time including night when there was no solar. Overvoltage from solar is well known and one of the reasons why there are restrictions on solar installs in a distribution network catchment area. The ABC report appeared to try and argue that overvoltage was not due solar as night voltages were in the upper end of the 246 to 254V range. At night the reported measurement was around 241V (or the nominal 240V for the Australian domestic network).

I also find it hard to beleive that a voltage of 254V (?) would result in an increase in a power bill of over $1000. If one assumes that this is a normal household, this would mean a increase in the order of 40%. This number does not sound right.

In addition to this, the ABC showed alleged testing of a LCD TV at different voltages and then making a statement that it is nit known the impact on such devices. Impact on such devices is likely to be zero as most modern electronic appliances have transformers which drop and regulate voltages. If there is any impact, it would be on the transformers and not the device. Most of these tranformers also have a wide operating voltage to allow operating worldwide.

Unfortunately the ABC appear to intentionally have tried to muddy the waters and possibiy had an agenda fo try and discredit the argument of residential solar overvoltage. Maybe the reporter/someone at the ABC was denied grid connection for their PV system on the frounds of overvoltage and they used their own media to mount a campaign trying to discredit a known fact.

I don’t know, but the report was a bit fishy, lacking facts and sensationalism at best.

It is also worth noting that there are network solutions for voltage clipping and boosting, but these are expensive especially if installed at the local distribution level. They are usually used on the high voltage neteorks to protect the network from failure/faults.

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The ABC did indicate that they could take up to 30 days to respond to my complaint re the article.

I await the ABC’s wisdom and response. Hopefully the reporter attributed to the article is not hung out as there will be an editorial team behind what is published who should have been more astute. There are numerous contradictory statements in the later part of the report that should have set the alarm bells ringing on what they had being incomplete or unreliable.

@gordon by his examples reminded me that understanding AC power is a complex science. It is more than a simple DC torch which glows brightly with fresh batteries before dimming as the batteries expire.

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One of the main informants in this article is Richard McIndoe who is a principal of a company that supplies devices to remedy problems with overvoltage. The firm Edge Electrons publishes case studies that claim considerable savings from some who have installed the device.

  • Overall the web site is slickly presented but light on detail.
  • There is no information about how the savings were measured.
  • There is much reference to interactions between the network and solar inverters but it is not clear if the savings claimed are only from reduction of network consumption or include enabling feed-in where it might not happen otherwise, or even if the system is of any value without your own solar.
  • There is no broad study available showing the circumstances in which savings may be made and when not, only selected case studies.
  • The firm and the product seem to be only a few months old.
  • I cannot find any reviews of performance much less an independent study of this device.

Looks like a job for Choice to test and reveal if Edge Electrons deserve a medal or a Shonky.

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You will have to let us all know what the ABC response is.

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Hi Fred123
The standard voltage for Australia changed to 230-volts +10% to -6% (AS 60038) many years ago. It is now in line with the EU.
I quite respect the ABC, but believe that the article you referenced is nonsense, almost (I hate to say this, but) “fake news”. Line voltage on the power system will fluctuate quite a lot depending on the system load. As many correspondents have commented their voltage varies substantially over and under the 230-V standard. BUT no matter what the voltage, no-one is being “force fed electricity”!!
Power in Watts (kiloWatts) is a function of voltage and current, plus - depending on the load -resistance. Generally, the increase in voltage will only cause a higher power consumption for restive loads like toasters, kettles, ovens and hot water heaters. For electronic and inductive (motors) loads there is a different effect which is more complex to explain.
With the toasters, kettles, ovens and hot water heaters the higher voltage will result in a higher current and therefore more power. But, the higher current will mean that the element will be hotter and take less time to complete their task (of course an oven temperature is thermostatically controlled so there will be no change). The result will be that the function will be faster (ie the water will get to temperature sooner) - and as our electricity cost is a function of power and time, ie kiloWatt-hours (kWh) then the resultant “electricity consumption” is the same!

In saying that, an over-voltage IS a problem, but so is UNDER-voltage. An over-voltage can cause anything in the electrical system to fail. The various parts of the system are designed to cope with an upper voltage, generally the rating is something like 250-Volts, and going over that can cause a failure due to overheating or burnout. An under-voltage (brown-out) will cause some devices, especially with a motor (like refrigerators), to burn out as they have to work to hard to deliver the power (watts) required.
If anyone does have a voltage problem they need to report it the their retailer. It is in their interest to get it fixed as they will suffer the consequence of “bad” voltage just as much as anyone!

Also, there is no such thing as a “voltage filter” as described in the article! There are filters which cut out ‘voltage surges’ but they are quite different! If you have any sort of sensitive electronic device, like TV or computer, you should have a surge diverter! They cut out momentary (ie seconds) high voltage surges that will cause damage. An extension of the basic surge diverter is one that protects against lightning strikes.
If there is a real voltage problem in the local system the way it is rectified can be quite complicated and expensive. It all depends on the cause and location.
And please do not use a multimeter to check your voltage! It can be very dangerous and cannot give anything but a momentary glimpse of what is happening - and it is only an ‘open circuit’ voltage which could be misleading. It is better to have monitor voltage and current over a week or two, than stick a probe into a power point for a couple of seconds!

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Hi Allan,

Glad you have added your voice and critical observations on some of the technical issues with the ABC news report. There are often a number of different ways of looking at the same information.

Your observation re the effects of reduced voltage are useful. AC machines are more efficient at higher running voltages than lower voltages. The distribution network can carry more power more efficiently at higher line voltages. Reducing the network distribution voltage increases the load currents required to deliver the same power or reduced currents will to be drawn for longer periods of time depending on what is being powered. This can be counter productive and also damaging. It may be wise not to go down that “rabbit hole” for now as it is more a giant sink hole in it’s complexity.

Just a short note that while the standard AS 60038 has been around as you noted for some time, the actual voltage of the supply is set in each state directly or indirectly by Govt Regulation, and their distribution entities, or now private operators.

I have not looked to the other states to confirm their situation. For Qld the 240v +/-6% standard has been in place until Oct 2017-2018. There is now a transition period in place based on 230v +10/-6%. The plan is to complete the transition to AS 60038 in 2020 to be fully compliant with 230v +6/-2%

In Qld the distributors Energex in the SE and Ergon regionally, both of which are owned by the Qld State Govt manage the regulation or setting of voltages on their networks.

There is plenty of on line information to refer to. Anyone interested might like to refer to the following release by Ergon re the changes, or the more recent advice in a previous post.

https://www.ergon.com.au/network/network-management/network-infrastructure/230-volt-transition

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In high voltage networks, there are things like SVCs (Static Var Compensators) and Cap banks which help regulate/stabilise the voltage on the network by shifting generation and load. I am not aware of these being developed for the domestic/residential user.

In a previous life, I was involved in SVC construction projects. I recall the cost of a SVC on the network is significant, but the return on investment pays off in the long run.

Maybe what the ABC meant were voltage regulators instead of voltage filters?

Voltage regulators exist but not sure if they are designed for long term overvoltage.

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The Edge Electrons device is described in their material as follows:

"EdgeIQ has streamlined voltage reduction through a fast
and direct “one stage” AC-AC conversion process. It does
this using proprietary Power Control Software which
is fully bi-directional, meaning power can be passed
backwards and forwards while maintaining constant
regulated voltage for the premise.
EdgeIQ passes fluctuating voltages through high-speed
microprocessors, which read and correct voltage 18,000
times per second and reduce it to a steady, uniform level. "

Does this mean anything?

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Thanks @phb.

Technical speak here in order of complexity - rabbit hole, sink hole, worm hole, Static VAR Compensator!

The last of these is all to do with managing reactive components of AC power which can change rapidly and destabilise a distribution network. It exceeds my mental capacity to reliably explain here other than to offer a simple explanation of how Dr Who’s Tardis functions. I will simplify it by suggesting both systems have components of real and imaginary current or power, but in different ways. :nerd_face:

I will share the ABC’s learned advice when it arrives.
Hopefully it will be more illuminating than an explanation of time travel? :thinking:
.

I’ve noted @syncretic most recent post. I’d be guessing and out of my knowledge base. There may be some genuine engineering in the so called filter. What the effeciency is, operating temperature range and other basic commercial specifications would be more useful evidence of a commercial product.

Any actual electrical device that functioned as an electronic buck/booster without speculating on its cost would need to be installed by an licensed electrical contractor. It would also need a type approval against a number of standards as well as network owners approvals before connection to the incoming household supply.

I wonder if that detail exists?

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There is no “Hallelujah” button, so this comment and a like will have to suffice :slight_smile: thanks for the voice of reason on a solid foundation - I would say that ‘nonsense’ and ‘fake news’ seem the same to me, but either way your points are well made.

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It gets even more intriguing!
This info-commercial appeared on the Energy Matters web site with due credit to an ABC program:
The problem of changing voltages in our powerlines has even been the focus of an ABC TV 7:30 Report program.

Interestingly in this latest release we now know a little more about the rest of the team.

From Energy Matters,
Wangaratta-born Neal Stewart is a scientist, inventor and co-founder and CTO of Edge Electrons.

Why the ABC did not simply run an independent program on the product as something new and decouple any reference to it from a cover story on high voltage issues on our networks is up to them to respond to.

At least for Energy Matters the headline claim of savings on power bills is less outrageous than the prior $1,200 a year?

EdgeIQ creator reveals how his voltage device cuts electricity bills by up to 10%

It is still potentially misleading and deceptive based on numerous observations.

The Energy Matters item still contains misrepresentation of technical fact.
Of the easier to challenge are:

  1. An increase or decrease in AC supply voltage of 1% will increase or decrease the total power consumed in the home and hence bill by 1%. False given all the prior discussion on how household appliances use energy.

  2. Boosting solar inverters feeding back into the grid to prevent inverter lockout sounds great, however the same principle applies to the booster operation. It too will legally need to limit it’s output to the same upper voltage limit as any solar system. If a standard alone PV system will not feed power back to the grid because of high grid voltage neither will the boosting function. It is even likely that the booster being dynamic may clip even more feed in than the PV system stand alone?

  3. The statement re the 230v supply and regulation standard is used to emphasise or exaggerate the benefits of the new technology or risks of not having such a device. Yet only a year previous the 240v +/-6% standard was perfectly ok! We are mostly all still using the same appliances. To be fair dinkum every individual household electrical appliance and device needs to be considered on its own as to what if any difference changing the supply voltage may have. There is no one universal answer.

Reality is how homes consume energy measured by the meter in the box as kWhrs. This is what is paid for. Whether this is supplied at 230v or 240v makes no difference to most things we use energy for. It has previously been noted, it will require the same amount of energy to boil the kettle irrespective of the voltage. It will cost the same and as others have said prior it may take a little longer. I could add that taking a little longer will see more fugitive heat loss from the kettle and will be less efficient than a fast boil at higher voltage.

The primary marketing for the Edge IQ device that it will significantly reduce power bills still does not align with science and physics. Any other benefits may also be questionable or of very limited benefit to most households.

There may be some real trial or prototype devices. It appears these may be based on known methods of high speed switching of AC power using reactive componentary for energy storage. There is sufficient published literature on how to regulate AC voltages with these methods. A patent application is a great way to protect IP. It is also a great way to limit more detailed scrutiny and analysis.

Perhaps Choice might be able to request one for evaluation with the support of one of the University’s Choice has a relationship with? Although it is the response of household power consumption to changing supply voltage that is important. The device may not be relevant.

Loop closed for me!

P.S. see following for my take on what the Edge IQ is a really a about.

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Voltage Optimisation,

This is what is really being promoted with the Edge IQ. It has been rebranded with targeted marketing and a twist.

The marketing perhaps also takes advantage of a degree of technical smoke around AC power and the actual distribution regulated supply voltages.

Voltage Optimisation is a widely discussed topic for business with high usage of electrical energy. It’s potential benefits depend on a detailed understanding of each situation. It is not a revolutionary concept and is also a topic of much conjecture as to relative benefit in the domestic environment.

Is it a benefit? It depends! The following is a little old and has an business/industrial scale approach.

A link to the Edge IQ promotion web site. Note that there is no indicative pricing. There are claims of paybacks in two years. There is also a claim of saving $6,660 over ten years on power bills. All unqualified in their promo header!
https://www.solariq.com.au

Edge IQ is just a modern electronic switching device to vary household AC voltage. Large scale solutions for large buildings and industrial scale premises have been around for decades. Suggesting the Edge IQ as technically a filter is not appropriate. It was the reference term used in the original ABC article. @phb was spot on in suggesting the device was really a form of voltage regulation.

The promotion of the product in the prerelease is in particular targeting solar power home owners.

It would seem very unlikely the savings suggested could be achieved in an average home with no solar PV. Average household energy consumption varies with typically averages from less than 4,000kwh to more than 8,000kWh annually. A 10% reduction at the upper end is 800kWh at 28c or $224 annually if it was my bill and I did not have any solar PV.

This assumes there is a genuine 10% reduction in electrical energy consumption available to a typical household.

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Around 50 years ago, the operators at the generating authority’s old Townsville system control centre were telling us about the problems that the grid was experiencing in the rapidly developing Western suburbs of Townsville.

At night when loads were light on the HV grid, they could simply switch in additional reactance to offset the capacitive effect of the transmission lines to correct the power factor.

However, during the day, and especially around dinner time, the local electricity board’s network could not cope with the load in these new suburbs.

There were problems from both low voltage due to overloaded transmission lines and from the ballasts in the fluorescent lights effecting the power factor to the point that residents were complaining that their fluorescent lights would not work properly and their frypans would not cook.

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Given the claims made in the link posted by Mark: EdgeIQ Pre-Release Offer | Edge Electrons, it has to be regarded as a scam. It is very reminiscent of the power factor correction devices that were supposed to save household money- incorrect, as domestic users are not charged for kVA, only kW, so improving the pf has zero effect on bills.
Maybe we should bring back the Peter Brock Energy Polariser (I’m sure forum members who have been around for a while will remember that scam!) to polarise the petrol molecules and improve fuel economy! Re-badge it to polarise the electrons bouncing around in your household wiring to constrain them and make them do more work! Think of the massive savings to be had!:money_mouth_face:

The EdgeIQ front page is full of misleading claims, such as: “Solar harvest is increased by up to 15%, giving you more electricity to sell back to the grid”. I’m calling BS on that, as modern inverters are over 95% efficient now, there just is not an extra 15% improvement to be had. I guess the “up to” is their out on that claim.
The grid voltage at the switchboard is what it is, no amount of jiggery pokery in a small box of electronics is going to change that, so it really is not possible to export more energy to the grid. If Vgrid is too high and the inverter limits output to stay within safe limits, the EdgeIQ cannot change the grid voltage, so would be unable to make any export increases there.

EM (my ex employer since my forum moderation job was outsourced to Hyderabad), have news items written that are sometimes based on press releases, and sometimes include any errors or excessive claims made therein.

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