power factor reducer/power saver plug - do they work?

Incisor

1carminestocky wrote: »

Absolutely not! My contention is and has always been that there are posters posting stuff on here and NOT being truthful as to who they work for. It would appear for too long that this forum has existed as some sort of cosy discussion group/caretl for people who derive their livelyhhoods from the energy companies (plus from the related industries, mentioning no names :rolleyes: ) If the 'average' punter reading this forum is to be able to evaluate the info on here in the correct manner, then I believe it is wholly right that any industry 'insider' should make it clear that they derive their income from the energy industry. It's common sense, really...

Let's be clear about this. He has declared that he is an Energy Broker, so what you say above is fair enough. If you thought I meant that being an Energy Broker was reason enough to give him a hard time, then I am sorry I gave that impression. It is however reasonable to expect that when he gives technical information, it should be accurate and not expressed such that people come away with the wrong idea - if that happens, he should be challenged. Which he has been.

Incisor

tomstickland wrote: »

Yes, I had a good think about it whilst I was doing something else and it all seemed very clear. All you have to do is measure peak voltage and current and the phase lag and you can work everything else out.

As the phase lag increases then the amplitude of the current also increases to keep the overall power integral constant.

Starting from the assumption of constant power but decreasing power factor, yes.

In terms of plant design, it's the higher peak currents that demand larger wires etc.

Anyway, for domestic customres, it won't make any difference to their bill.

Regarding that integral, it's the sort of thing we'd do as 1st year engineering degree.

x = 2*pi*t*f
where t is time and f is frequency
define instantaneous voltage as
v'=v * sin(x)
instantaneous current
i'=i * sin(x+y)
where y is the phase lag


y =vi [ sin(x)*sin(x+y)]
y=vi [sin(x)*(sin(x)cos(y) + cos(x)*sin(y)) (Trigonmetric identity)
y=vi [sin(x)^2*cos(y) + sin(x)*cos(x)*sin(y) ]
y=vi [(1-cos(2x))*cos(y) + sin(x)*cos(x)*sin(y)] (Another trig identity)

integrate over x

y =vi* [ (x - (1/(2*pi*f)*1/2sin(2x))*cos(y) + 1/(2*pi*f)*sin2(x)/2*sin(y)] (Integration of second term by parts)
This integral is evaluated for one cycle (x=0 to x=2*pi).
The sin(x) terms come out as zero, leaving

y = vi*2*pi*cos(y)

I might be a factor of 2*pi out, but the structure is right, looks far more complicated on here than on paper.

Yes, that's the idea. Strangely enough these days I remember the result and the strategy for getting it, but I never feel motivated to work it in full.

fatlad1971

fatlad1971 wrote: »

There is no such thing as power factor in electricity metering domestic or industrial
Maximum demand and HH sites have Kva charges , power factor does not exist

which is what i have said from my first posts

mirabelle

Morning boys,

Glad to see you all had a good Saturday night.

Has anyone seen nicjrdn. He seems to have gone a bit quiet.

SwanJon

1carminestocky wrote: »

Whilst I totally accept most parts of your post, SW,

SJ, surely

1carminestocky wrote: »

how many time on here have you ever recommended people using a supplier other than BG?

Probably the same amount of times I've recommended BG as a supplier - incredibly few on either count.

1carminestocky wrote: »

I'm not in any way suggesting you are 'dodgy' and I acknowledge that you have expertise with regard to energy issues but the fact remains you are in the employ of British Gas and have already admitted you can make commission on sales.

Yes, it is possible for me to make commision on sales, however, it is almost impossible (entirely impossible within the rules) for me to use this forum as a way of collecting potential BG customers. As such the possible commision I earn from one part of my role is irrelevant to my comments on here.

1carminestocky wrote: »

That's why I genuinely believe it's in the interests of the 'other' people on here for them to see who you work for and who you derive your livelihood from. Don't you at least accept my point here? It's not OK IMO to point it out 'in your first post' either, what about people who join the debate on here at a later date? They wouldn't necessarily know who you are and who you work for..

see above.
Now, do you have a pension? Can you guarentee me that that pension scheme doesn't own any energy suppliers shares? Does that mean that you shoudl be stating that at each comment too, or seeing as it has no effect on yuor knowledge or opinions is it irrelevant?

mirabelle

nicjrdn wrote: »

Does anyone know if these things are any good and are they legal? Someone told me about them and apparently they can reduce your electricity bills by up to 30%. I found one for £15 on an eco site (http://www.windtrap.co.uk/Energy-Saving-Products/Power-Factor-Reducer.htm) and if they do what they say why are they not more publicised?

nicjrdn - I see it's your first post - Bet you're glad you asked.

tomstickland

To the OP: The answer is a definite NO!

Denarius

Hi, I know this thread is old, but I've just been researching this. I read yr comments and then the company I had looked at on the web sent this report. What do you think of it?

//plugandsave.com/images/stories/proof/SavePowerUnivStudy.pdf?utm_source=getresponse&utm_medium=email&utm_content=Scientific+Proof+Our+Power-Savers+Really+Work&utm_campaign=pasresidential


cheers

moonrakerz

Denarius wrote: »

Hi, I know this thread is old, but I've just been researching this. I read yr comments and then the company I had looked at on the web sent this report. What do you think of it?

//plugandsave.com/images/stories/proof/SavePowerUnivStudy.pdf?utm_source=getresponse&utm_medium=email&utm_content=Scientific+Proof+Our+Power-Savers+Really+Work&utm_campaign=pasresidential


cheers

Well, well, well !

Second post: praising Snake Oil.

Cardew

That garbage report - "blind-em with science" - has been around for a long while and posted on MSE.

As stated previously, and above, it is just snake oil.

No relevance at all to UK electricity consumption in domestic properties; except perhaps if you have a 40 year old fridge and then it could reduce your bills by pennies.

Given the emphasis by the UK Government on cutting electricity consumption, don't you feel that they would make companies fit them for free if the gimmick device made the slightest difference.