Gadgets to Reduce Electric Meter Readings-Its a Con!

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
22/09/2009 21:48

People keep asking me if they really work. They claim that by plugging one of these gadgets into any socket you can reduce your electric bill by up to 30%



It is a real con. It may reduce the electric current that flows through your meter but it does not reduce your bill. How come? Your meter measures the "power" you draw from the system and not simply the "current". Are they not the same thing? Not quite!



Here is the technical explanation for those who are interested:

A "Capacitor" or "Condenser" as some call it can store some electrical energy. You can charge a capacitor by connecting it to a battery. However, if you connect it to an alternating supply, it will charge and discharge continuously. Our city electricity is 50 Hz. i.e. it goes positive and negative 50 times in a second-faster than any woman that can change her mind Everytime it becomes charged positively or negatively it stores energy and it gives up its energy in between.



So a capacitor can take power in and

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
22/09/2009 21:49

So a capacitor can take power in and then give it back 100 times in one second. It does this by drawing an electric current but this current leads the voltage by 90 degrees. On the other hand an "Inductor" or some sort of coil does a similar thing: it stores energy by magnetism and then it gives it up and energizes again when the voltage goes to the other polarity. So, an inductor also charges and discharges energy 100 times in a second. However the current drawn by an inductor "lags" the voltgage by 90 degrees. Hence when a capacitor charges the inductor discharges and vice versa. So the two together can cancel each other out.



An electric motor acts as an inductor to some extend. So it does some charging and discharging of energy. Thus an electric motor does not use all the energy it draws from the system and gives some back. The electric meter registers the net power and not the portion which is taken and given back all the time. Sometimes the net power is called "Active" power a

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
22/09/2009 21:50

... called "Active" power and the one that is taken and given back "Reactive" power. The electric meters only records the active power.



The gadgets on sale contain some capacitor in them and thus partly eliminates the reactive power, the portion that is not recorded by the meter in any case. Hence a capacitor can reduce the total current but not the meter reading.



This is the best I can do with no pen and paper and some drawings.

ismet

http://www.elkocyprus.com

proger1



Joined: 18/04/2009
Posts: 2919

Message Posted:
22/09/2009 22:04

I think judging by your description in the first post Elko, all the women I have met have been suffering from an inverted DC current because they could easily manage 50 negative thoughts in 1 second but never the positive ones.

Very good explanation though, thanks

Hector


Joined: 26/08/2008
Posts: 2352

Message Posted:
22/09/2009 22:16

Memo to self - if I ever have the honour of meeting Ismet don't, repeat don't, mention electricity.

No1Doyen


Joined: 04/07/2008
Posts: 16617

Message Posted:
22/09/2009 22:17

Hector..

Brinsley


Joined: 04/04/2009
Posts: 6858

Message Posted:
22/09/2009 22:18

Ismet



I'm confused. So what is the electrical current which passes between a boy and a girl across the dance floor resulting in a negative earth feeling the following morning?!



Richard

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
22/09/2009 22:29

Hector,

I promise not to mention electricity or law when we do meet, both are shocking and stressful subjects.



Richard,

When you are dancing on the floor, if you get a little electric it gives you a nice tingle and very enjoyable but if it goes over 32 milliampers you can get a fatal shock at worst or at least give you some burning feeling the next morning. Its best to touch her as often as you can to minimize the effect of the shock and better still finish off the night with a bottle of wine together which is known to discharge any electricty left about.

ismet

AlexF065


Joined: 07/09/2009
Posts: 271

Message Posted:
23/09/2009 12:55

The only think to reduce energy consumption is a thing called an owl

This gadget shocks people about how much energy in £ they are using and they start turning lights off in rooms they are not occupying they start turning off the televison at the mains they no longer leave it on standby or if they cannot reach the plug they buy standby monitors that can sence a TV or other appliance left on stand by and turn it off for them

you might be suprised to know a TV left on standby cost £36 PA in the UK at current KWh charges

a mobile phone charger left in a switched on socket nolonger attached to the phone cost around £12 peryear

Ok these figures dont seem much on the face of things but walk into the average teenagers bed room the electrical gadgets in these rooms make curry's look like a corner shop and my niece's room was costing my Brother £165 a year

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
23/09/2009 13:17

Hi elko2,



You may have seen my postings about credit card type pre-payment electricity meters supplying air conditioners to stop holiday rental property owners getting a "shocking" bill from KibTek after their guests abuse their a/c.



This meter will not save any electricity on its own, but it may make people use less.



What is your view on them?

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
23/09/2009 15:00

Vaughan,

I am sure I did recommend it as a very good idea. You must have missed it.



How did you find my post above as a technically minded person? Was it easy enough to understand or did I go over the heads of many? I am used to explaining things with drawings but I had to do it here with no drawings.

ismet

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
23/09/2009 15:24

Hi ismet,



Thanks for your recommendation.



Having spent 3 years studying at Plymouth Polytechnic, Dept. of Electrical Engineering, this kind of theory was drummed into us until we understood it. However, it isn't the most "electrifying" of subjects. This gadget you refer to may be an attempt at power factor correction, and in large commercial/industrial installations this is desirable, but I doubt any savings could be made in a domestic application. There are some decent diagrams available at http://en.wikipedia.org/wiki/Power_factor



Although folks like you and me might be quite passionate about our subject, others might nod-off part way through some of the explanations we may give from time to time.



Ah, well! Anoraks of the world unite!

elkiton



Joined: 15/03/2009
Posts: 514

Message Posted:
23/09/2009 15:52

Well, Power factor correction has been around for a long time now and is usually used when you have something along the lines of an arc-furnace distorting the PF outside its limits of .9-.95 this usually results in the current drawn being an extra 40% or so to do the same amount of work, and the supplier being P***** off as his true sine wave, ain't so any longer!.

I would have thought that as the meter is only interested in KW hours,the bulk of the house loads here are inductive (from motors) and that true power factor correction might theoretically reduce the bill, however the powerfactor distortion for one house is relatively small and the savings perhaps insignificant?

Does anyone know if Kibtek apply power factor correction to their supply lines?

see this link for the equatioins

http://openbookproject.net//electricCircuits/AC/AC_11.html

best regards TonyE

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
23/09/2009 16:04

Hi TonyE,



Carefull!! This could turn into a geek-fest.

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
23/09/2009 16:20

TonyE,

The power factor correction does not affect the reading of the meter, hence absolutely no savings to the consumer. As far as I know, Kib-tek do not measure KVA drawn and thus do not penalize the industrialist with poor power factor but I may be wrong on this. They certainly monitor it in England. I do know that Kib-tek carry out some power correction on the 11 KV lines using banks of capacitors. I am not sure if they use overexcited generators to act as a capacitor.



I think it was the year 1977. I was the manager of the Steel pipe factory in Famagusta. One day one of my engineers informed me that engineers from Kib-tek were noting the size and power factor of each motor. Then they came to see me and told me that they would charge extra for the "Reactive" power they estimated from the list of motors. I laughed and showed them the bank of capacitors already in place that kept the power factor to better than 0.95. I saved my salary ten times that day.

ismet

elkiton



Joined: 15/03/2009
Posts: 514

Message Posted:
23/09/2009 18:38

Elko, Kibtek probably have one of the spare (unservicable) generators runnng in reverse as a motor to do the correction it lol



For resistive loads only, KVA and KWatts are the same thing....KVA differs on reactive loads to KWatts, so does not reducing the reactivity through applied PFC logically reduce the Kwatts rating too ?



FYI There is a fabulous utube video of a powerline breaker in the usa coming open with the PFC inductor still in circuit, can't remember the url but worth looking at, the arc is something wondrous to behold.



Never mind the Geek fest, there is enough nonsense spouted on this forum, a bit more will probably go un-noticed!



best regards

TonyE

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
24/09/2009 17:44

Tony,

I have just noticed your post above.

KW is the active power and if you multiply it with time it becomes KW hour and recorded by the meter. KVA is made up of active power (KW) plus the reactive power (the part which is taken and given back in equal portions). So when you add up active plus reactive power vectorially it gives you the KVA. Sorry to introduce a new term here (vectorially), it simply means adding two lines up not in a straight line but in this case at 90 degrees like in a triangle i.e. 3 + 4 = 5 (3 square + 4 square = 5 square).



So by pfc, you try to eliminate the reactive power or better described as "imaginary power". So your KW remains the same.



I have met many young electrical engineers who graduated from various universities in Turkey or Cyprus. They all know how to calculate everything and thus how to do pfc but none of them had any clue as to the real cause of the problem i.e. how exactly it came about. Once I had a good audience telling them what it was all about and why the current in a capacitor leeds the voltage by 90 degrees and the current in an inductor lags behind by 90 degrees. All explained from first principles. No bs.

ismet

http://www.elkocyprus.com

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
24/09/2009 18:11

Oh I forgot about the generator used as a motor. These are syncronous motors/generators. You can run them as a motor but because they are syncronous (unlike the ordinary asyncronous motors used in everyday life), by adjusting the excitation current the motor can also act as an inductor or as a capacitor, very handy. In London, the problem was having too much capacitance in the system due to underground cables, thus we used them as inductors to achieve pfc. Once (year 1966) we took out one of these machines from generation for experimental purposes and we had to give it back for the peak hour i.e.5 pm. One of the control coils got stuck and burnt out. They all had a real panic. I was a graduate trainee with no responsibility at all. I saved the day by getting a winding machine quickly from our laboratory and wind it. It was back in service half an hour late. Fortunataley we had no power cut at Battersea, where all this took place. Good old days.

ismet

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
25/09/2009 09:55

Going off on a slight tangent, has anyone like myself and possibly Elko2 and TonyE noticed that they have become used to, almost immune to getting electric shocks over the years?

I have had many in my time and although it makes me jump and makes my heart beat faster for a few minutes, it hasn't killed me, yet!

I must admit I do treat 3-phase with a lot more respect than 240V.

HV still frightens the cr*p out of me.

Brinsley


Joined: 04/04/2009
Posts: 6858

Message Posted:
25/09/2009 10:19

Vaughan



And I thought you were bit of a 'live wire'!



Richard

keithcaley



Joined: 13/06/2008
Posts: 2521

Message Posted:
25/09/2009 10:34

Vaughan,

I thought that it was just me!

The worst bit is when your muscles lock, and your hands clench tight round the conductors that you're trying to let go of. Usually falling down breaks the circuit

I'll tell you what though, 25KV from the back of a TV or Monitor makes your teeth rattle!

And Microwave oven HV circuits pack a bit of a punch...

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
25/09/2009 11:01

Keith,



50's technology Radar used very high voltages and components were known to detonate now and again. Working on them while they were running also tended to cook you slowly - the tingeling in your tooth fillings told you something was not right!

elko2



Joined: 24/07/2007
Posts: 4400

Message Posted:
25/09/2009 11:05

Unlike viruses developing resistance to certain antibiotics, I don't think you can get used to any shock but you learn to take the right precausions so that you can get over it lightly. I always supply my test gear through a 32 ma RCCB so if I do get an electric shock the power hopefully will be switched off before it kills me. You have to respect electricity more than you ever respect the advocates

ismet

http://www.elkocyprus.com

PS: I had over 400 unique visitors this month and roughly half of them were directly from C44

TRNCVaughan


Joined: 27/04/2008
Posts: 4578

Message Posted:
25/09/2009 11:25

I think half of a shock at least is surprise closely followed by fright.

Once you get used to getting shocks, there is less surprise and much less fright.

I always feel an adrenaline rush which must be what makes my heart race.

I could see where it could almost be addictive.

Tenakoutou



Joined: 27/07/2009
Posts: 4110

Message Posted:
25/09/2009 12:17

A plumber, standing knee-deep in water in a trench with his apprentice, was trying to explain the danger of electricity.



Suddenly, a huge 'Richard the Third' came floating down, followed by the 'paperwork'.



'You see, my son - THAT you can see - but don't touch that cable over there, cos it'll f*%king kill ya!'

Tenakoutou



Joined: 27/07/2009
Posts: 4110

Message Posted:
25/09/2009 13:17

'BANG>>>>>>>FIZZ.'



'Oh heck', said the plumber, 'too late - another charred apprentice!'