I have the estates people where I work being given a sales pitch by PowerPerfector.com

Powerperfector supply effectively what are transformers that you stick on the mains supplies to campus environments to "optimise" the output voltage across the campus to 216V to 220V.

Quoting from their guide "A guide for site engineers, contractors, or maintenance personnel"

Following the installation of a powerPerfector the supply voltage will be approximately 220V at the electrical supply point, and may be as low as 216V at the furthest point from the incoming source. This is close to the optimum supply level for your equipment and will allow it to operate with less stress and more efficiency.

NB The statutory minimum supply level of voltage in the UK is currently 216V and this will change to a minimum of 207V in June 2008.

We have a number of automatic changeover panels and UPS systems, which I guess need to have their settings changed to take account of the lower supply voltage.

But does anyone have any views about this kind of technology. Surely if the nominal voltage is decreased, the current required by an item increases, etc? And does anyone have experience of the energy saving claims of the solution?

Thanks in advance.

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Tomo.

Have a look at the discussion thread "Voltage Optimisation" down the page - this issue got a good airing there and I think you'll find answers to (most of) your questions there.

Jono

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Jonno

I'm no expert; but as someone who has worked with 'optimisation' (albeit in another arena), I am a little cautious about the term optimisation in this context.
I can readily accept that if equipment is designed to achieve 'best efficiency' at, say, 220V, then running it at any other voltage could be sub-optimal. However, I'm sceptical about the apparent one-size-fits-all approach. I got the impression that there is an underlying asumption that (nearly) all equipment in the UK is really designed to operate at 220V; whereas our normal supply voltage is 240V (230V delivered), implying that he equipment is unduly stressed; but is that really true? Might not our long tradition of 240V supply mean that much of our existing equipment is actually designed for 230V? What are the down-sides of running some equipment at too low a voltage? I don't know enough about this aspect.

Obviously there is the indisputable fact that for some equipment reduced voltage will lead to reduced consumption and reduced cost; but won't this be at the price of reduced useful work from the device? I mean, if one is going to have, say, dimmer lighting - then why didn't the lighting designer simply desgn for lower light levels in the first place?

I summary, then, I would expect that matching the supply voltage to match the 'best-efficiency' point of operation of all electrical equipment could be a worthwhile optimisation. However, I question whether a) the 'best-efficiency' point is known for very much electrical equipment in use (b) whether on an existing site all equipment would have the same/similar best efficiency voltage (c) how to best determine a single voltage (not necessarily a lower votage) that achieves an optimum weighted summation of all the equipment efficiencies, (d) whether best-efficiency always (or ever) equates to a lower voltage.

It's an interesting topic.

Obviously if one lowers voltage then one will reduce power consumption - but that is not at all what Engineers mean by 'optimisation'.

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khales

Edited: 02 April 2008 at 10:04 AM by khales

There are some other questions on this in the Wiring and Regs forum.

One of the issues that has not been raised so far is the question of embedded generation. The G59 protection settings are at present determined by the local voltage and set at nominal values of + or - 10% of 230 or 240 volts. If the system voltage is reduced by voltage optimisation the G59 protection will require resetting... presumably after a period of nuisance tripping is experienced.. I can think of one site where the problem was so bad that the Generator had to be run in island mode until resetting and witnessing by the DNO could be arranged. Can someone tell me if there are similar issues with UPS and can it be easily remedied?

Thirty years ago, I have seen in a project a SERVO CONTROLLED VOLTAGE STABILISER where the output voltage of a 10 MVA 110KV/11 KV output was stabilised.This transformer has an ON LOAD TAP CHANGER.The output voltage was sensed by electromechanical means and the tap changer acts to correct voltage.

But now a days it is electronic. Electronic means, first the output voltage is changed to DC and then inverted.Since there is no battery in the circuit, output voltage stabilisation against transients is difficult and costly filters are required.

But in case on an inverter or a UPS, rectified voltage is used to charge a battery and inverted. But I have seen UPS ranging from one KVA to TEN KVA, BUT NOT TEN MVA.

Optimum output from any equipment is obtained when the voltage supplied to it as per the specification of the manufacturer.

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Best wishes & regards
N P NAIR, MSc (Engg), C Eng, FIE(I), MIEE,Sr MIEEE.

1. What is PP's theory of operation? Can anyone provide wiring diagram, and how it is installed?

2. Please can anyone show how, by reducing voltage, you can save(Kw, and Kwh) 13%, and 20% for customers?

3. Can you save energy(Kw, and Kwh), even if my site has a low voltage condition?

4. Since this is a Japanese product, can you please provide some Japanese Government endorsements relating to energy savings in all cases?

5. Can you provide us with three or more engineering case studies, showing the actual measurements, and verification of the savings?


Thanks Greg

Perhaps I am a little sceptical about the claims made by this equipment. It appears to adjust the voltage after the main incoming supply which will optimise the power usage. But you do not get something for nothing, I can see that it will have an affect after the voltage correction but power in does not equal power out and there must be losses. It also claims to balance the loads, how does it do that?
Harmonics..... yes I can see that it would have an effect on the incoming supply as it appears to be a large inductance and this will affect harmonics. Inside of the protected voltage zone I cannot see how they can claim to reduce harmonics as most harmonic protection must be done at the equipment to stop it resonating around the supply source.

Sceptical but can be changed with proof.

Fredman, suggest you have a look further down the page at'Voltage optimisation'.
On my contribution of the 31st Oct 07 there was a deliberate error, at least thats my story... The article should have said that the Tx was fitted UPSTREAM of the Distribution Board.
I agree about your comments on Harmonics, any transformer will do that. I 'd like the load balanced bit explained to me
I 'm still of the opinion that there is a place for this technology with certain types of purely lighting load. I can tell you from first hand knowledge that using it with other loads which have not been carefully thought can be problematical. I hesitate to say a great deal more because I have a commercial interest in this field.

Very simple. But you will have to assume that more than 80% of your load consists of INCANDECENT LAMPS. Here voltage reduction consumes less power and result is LESS ILLUMINATION.

It is a way of cheating. When I was less than ten years old in year 1950, my father told me this. There was an advertisement in local news papers that killing house bugs is guaranteed IF ONE FOLLOWED INSTRUCTIONS CORRECTLY. Many paid hefty sums and the equipments arrived for them.

The parcel consisted a porcelein plate and its hammer usually used to crush to powder small medicinal tablets. Also a pair of FORCEUPS. Instructions were:

Take the bug with the forceup, keep it on the porcelein plate and crush with the hammer. !!!!!

Legal experts then clarified that no legal action could be taken.

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Best wishes & regards
N P NAIR, MSc (Engg), C Eng, FIE(I), MIEE,Sr MIEEE.

Edited: 17 March 2008 at 04:27 PM by ernairnp

Thank you ernairnp for your responce,

This product "Power Perfector" is of some intrest to me. I am looking to make savings on my plant. I understand that there are savings to be made in power quality BUT not just in voltage reduction.

I have several transformers ranging from 1000 KVA to 2000 KVA with small loads of 300 amps per phase to larger loads of 900 amps per phase and lighting is spread across all transformers. My main loads are printing press machines which have a number of electronic interfaces and from time to time they will stop if we have a low voltage dip from our supplier this is very costly to us.

My concern is if I was to install Power Perfector which claims to be able to save me KWH of around 10%, what will happen the next time we get a dip? our voltage is around 405 to 412 depending on the load condition.

I have also been approched by a company called "Electroflow Solutions". They are making simlar cliams on savings, not on voltage reduction but on overall power Quality.

Have you heard of this technology?

Link removed is there web address I would be interested in yours and anyone elses opinions.

Kind Regards

Greg

Mr Nair, I'm not sure why we are talking about incandescent lamps. I associate those largely with household lighting. I guess that most industry/ commerce uses SONS/Metal Halides/Fluorescent tubes. All lighting (incandescent or otherwise) will have some degree of loss of illumination, against voltage reduction and power saving. The big question is does the power saving enjoyed justify any minor reduction in light output. For the vast majority of occasions the lighting reduction is minimal so no problems. Different types of lighting offer different savings and different reduction in lux. I can personally vouch for the fact that many establishments have a voltage that is higher than the norm. Remember that most devices are designed to work at a lower (European?) voltage than we presently have in this Country. An added benefit is that the lower voltage will result in longer component life. My own humble opinion is that if the Government is to meet its CO2 targets EVERYONE will have to get used to lower ambient light levels with more task lighting. I can think of a few retail stores where you almost have to wear sunglasses its so bright.

Hi,

I am also currently looking at voltage reduction means for reducing power consumption so I'll share my thoughts;

I believe that in an office environment savings can be made. Lighting is one that has already been mentioned. I think the reduction in lighting levels due to this would be acceptable, however, I would be concerned if this meant that extra task lighting had to be installed. This will counteract the reduced power consumption acieved from the system.

I also believe IT equipment can benifit from a reduced supply voltage. The switchmode power supplies in this equipment produce losses as they drop the voltage to the required level. The less voltage they have to drop then the losses they produce will be lower.

The UPS technology we use around our site can be set up for different input and output voltage ranges so should be capable of catering for a reduced voltage.

I don't believe there are benifits for heating systems, kettles etc. I accept that they will prodcue less heat output but they will be on longer to get the heat up to the required temperature, so the effect is counteracted.

If I do decide to install voltage reduction equipment, then I would install power monitoring prior to the installation and monitor the before and after loadings to proove its worth.

With regard to power quality, I think I am right in saying that harmonics in an electrical system produce waste heat, so reducing the harmonics reduces these losses and hence reduces power consumption. The success of this will be dependant upon how bad the power quality is in the first place of course.

Just as an aside to Greg, you may be able to modify the supplies to the electronic interfaces so that they run off switchmode PSUs that can take a wide input voltage range but will keep the output constant. Just a wild suggestion really as I don't have any details of your systems.

Kind regards

Donald Lane

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Do not confuse activity with achievement

Thanks Donald,

For your feed back I am interested to find out and have a better understanding of to products Power Perfector and Electroflow as both offer savings in KWH and the possible side effects of installing them as I am a big beliver that you do not get something for nothing if you understand my drift.

Mr Lane, As I have said earlier I have a vested interest in this topic and have been involved in it for a number of years. I work for myself in energy saving, PFC, Harmonics and voltage optimisation and embedded generation so you can take what I say with a pinch of salt if you want.
On the lighting many companies have task and ambient lighting and if you explain to your workforce what you are trying to do and the huge savings on CO2 most will accept a slightly lower level of ambient lighting. I should also say there are a large proportion of potential sites which could offer huge savings financially and CO2 with payback periods of 8 months who will not even 'trial' a system. Its all very well to sit back and do nothing but where are the savings that the government are looking for in emmissions going to come from?
You are correct about setting up voltages on associated equipment. I have recently been involved in adjusting some embedded generation for that reason and the costs were HUGE. I could say a lot more on this topic from first hand experience but I dont think this is the place!
The equipment I am involved with has an energy meter on it as standard and has had for 7 years. You can switch the optimiser in and out of the circuit thus getting a before/after comparison

Hi 944SE,
I would hope I am open minded enough to listen to other peoples views and respect their comments and not take them as a 'pinch of salt'.
I can also only comment on the equipment I have come across and none of that had power monitoring built into it. However I am sure there is plenty of equipment, including yours, that I have not yet found out about.
The reason I made comments about the task lighting is because it is not really installed on the site where I currently work. Extra task lighting is usually in the form of portable halogens or fluorescents taken out to the work area.
If I were to deliberately install extra task lighting, then that would incur a cost in both financial terms and power consumption and both of those must be taken into account within a project.
Your comments about convicing a workforce bought a smile to myself. I would say there are 2 parties that I need to convince, the old school variety and the accountant. I reckon those 2 parties have put more spanners in my load reduction projects than Screwfix have got on their shelves.
There are many areas that I have looked in to to help reduce power consumption, voltage optimisation is only one of them, power factor correction is another you have mentioned (and boy did that one get the old school going). Solar panel power and heating systems, wind turbines, combined heat systems, building insulation, does the heating really need to be set that high or the air conditioning that low? Energy management systems, VSDs I seem to remember someone else mentioning. Or how about just turning things off when they are not needed (real culture shock for some people) I am sure others can keep adding to that list.
Beleive me, I can perfectly understand your frustration at people who will not give new or alternative technology a trial, but the reality is that I work in a culture of convenience and financial justification.
I think until some parties realise that power and CO2 reduction is often a combination of multiple actions and technology that each make small reductions which all then add up, its always going to be a bit of a long haul.

Kind regards

Donald Lane

ps. I'll pre-apologise to any old school types or accountants I've just offended...

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Do not confuse activity with achievement

Mr Lane can I congratulate you on your 'open mindedness'. In my experience there's not many of you around. I do G59 commissioning of many of the systems you mention and in my opinion if you have a large area of lighting from a dedicated DB which feeds SON's, metal halides or old style Fluorescents [not high freq]that will give you as good a return from a relatively small outlay as any. If your running anything like 24/7 you should be able to get a payback of around 0.8 years.
I understand what you are saying about task lighting and you are the best judge of what your workforce requires. I just see so much wasted opportunity.
I repeat where are the government going to get the CO2 savings they are committed to? Maybe they have a scheme to price us all off the roads.
regards

Can anyone give me any views of a sysetem called ELECTROFLOW good or bad?

Thanks Greg

1. ENERGY CAN NEITHER BE SAVED NOR CAN BE DISTROYED.

2. IF YOU SWITCH OFF ONE LIGHT, THE % SAVINGS IS INFINITE.

3. THE BASIC ISSUE IS FIRST YOU PLAN A JOURNEY IN A FOUR WHEELER TAXI (CORRECT ILLUMINATION). THEN YOU TRAVEL IN A THREE WHEELER TAXI (SAVINGS BY REDUCED ILLUMINATION). DEFINETELY YOU WILL SAVE.

4. FUNDAMENTAL IS HOW MUCH LUMENS YOU WANT ? THEN THE NEXT QUESTION IS WHETHER YOUR ACTION KEEPING LUMENS CONSTANT CAN BE ACHIEVED ?

NEXT WHAT IS THE CAPITAL COST FOR THIS ? WILL IT COMPENSATE BY ENERGY SAVINGS?

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Best wishes & regards
N P NAIR, MSc (Engg), C Eng, FIE(I), MIEE,Sr MIEEE.

Edited: 27 March 2008 at 07:31 PM by ernairnp