Power Factor Correction - Scam Review
Submitted by open4energy on Sun, 12/27/2009 - 18:08
Scam Opinion by open4energy
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If you are concerned about the amount of electricity being used by a heat pump or air conditioner motor, the best way to save energy is by installing a smart thermostat and one of the energy control systems included in our directory.
All power factor correction technologies claim to reduce your electricity bill by using capacitors to correct/optimize the power factor of the electricity being consumed in your home. They claim that an improved power factor will help electrical motors run more efficiently, extend the life of electrical appliances, save light bulbs and eliminate static interference.
There is truth in the fact that our homes have devices which consume electricity at reduced power factors. As an example we know that "CFL light bulbs" have a Power factor of between 55% and 70%, while incandescent light bulbs have a power factor of 100%. All electric motors, including fridges, air conditioners, fans and computers generate reactive power which will affect a circuits power factor.
Based on the above information it could sound logical that a pfc technology would save money for a home owner. But this is NOT a correct conclusion at all. Improving a consumers power factor will mostly save a "negligible" amount of electricity. I have correct my earlier opinion of "NO saving" to "usually negligible" thanks to an informative discussion with the founder of V-Blox Mr David Mulvaney.
Mr Mulvaney contacted me regarding his company and said "I want you to know we do not recommend power factor correction in homes and I will be the first to tell you that savings if any would be negligible". Noticing that his company is on a list of "imitation KVAR products" published by a KVAR distributor, I listened to his version of the story. I will be writing a separate posting on how it seems that the real pfc scams have developed. I did find all he said to be professional and reasonable.
Mr Steve Fish, CEO of KVAR Energy Savings Inc. also contacted me. He said "we are a professional organization and will take back any KVAR product that fails to reduce the electricity bill by less than our guarantee of 6%". According to KVAR, they capture and store the reactive power (var's) generated by an electric motors while it runs. We have agreed to conduct tests with KVAR to quantify any reduction in electricity by storing these "captured" vars in a capacitor, and serving them to the motors when required.
There is clearly an issue here, and both CEO's did acknowledge that their resellers were capable of "overzealous selling" - I suggest that all consumers be vigilant when investigating "var" or KVAR related savings in their home.
Power Factor is one of those subjects about which there seems to be a great deal of confusion and many misconceptions. The culprit is the the assertion that power factor = cos(Phi), Phi being the phase shift between voltage and current. While this is true under certain ideal conditions, there are many real-world instances where it is quite incorrect. This article will give you a basic introduction into power factor, and explain why cos(Phi) is not the whole answer.
The Basics
If you connect a sinusoidal voltage source to a resistor, current will flow, power will be dissipated in the resistor and the resistor will heat up. The current is given by I=V/R and the power is given by P=I*V or P=V²/R. The voltage and current are the rms values.
Figure 1 shows the waveforms for this experiment. The top blue waveform is sinusoidal voltage. The voltage is 1V rms giving a peak voltage of 1.414V, The red waveform is the current. It is 1A rms, 1.414A peak. (If you are awake you will deduce that the resistor is 1Ohm). The green waveform is the instantaneous power, i.e. the product of voltage and current from moment to moment.
At the left hand vertical line the voltage and current are both at their peaks, so the power instantaneous power is: 1.414V * 1.414A = 2W
At the right hand vertical line we are at the negative peaks of voltage and current, so the instantaneous power is: -1.414V * -1.414A = 2W
It should not take too much imagination to see that the average of the power waveform is 1W.
Please follow this link for the complete article titled Power Factor: Dissipating the Myths published by David Stonier-Gibson of SPLat Controls. We thank him for the permission to publish this introduction!
When the power factor is less than 100% it means that there is a phase shift between voltage and current. Consumer tariffs are based on Real Power, only the electricity actually consumed by a device. The consumer electrical tariffs include provision for the losses which this "phase shift" might cause the electricity supplier.
It is true that electricity suppliers need to manage their distribution networks, and that power factor IS one of the factors that impacts their distribution losses. It is also true that large industrial users are charged a penalty for a net power factor of less than 85%. But distribution losses will not be solved by consumers. They are aggregate issues that can only be solved by the utility companies "the smart grid" in partnership with industry and device manufacturers.
Power factor and power factor correction are indeed subjects that we should be aware of, but it is "near fraud" when excessively marketed to home owners as a way to save money on their electricity bill.
We have an overview on "Power Factor" and the definitions for real power, apparent power and reactive power for those who would like to understand more of the technical details on this topic.
One of the most disheartening aspects of all these scams is the amount of money the perpetrators seem to have for promoting and advertising them. As an open source publisher, dependent on contributions and advertising to pay our way, there is little more frustrating to me than the way Google is being abused to promote these scams. I understand that there is little they can actually do about it, for they are not the internet value police, and imagine how we would feel if they did make value judgments on our content.
I believe the answer is for us publishers to block all adverts from these scam domains. And for our readers to value our content with your visits, comments and links. Think of reading these pages as being a part of a virtual internet energy scam watch, where you can help expose their theft and send it to the black hole of "never seen" internet search results.
If you are uncertain as to the accuracy of open4energy's opinion we suggest you review this study by ScienceDaily - (Dec. 18, 2009)
"If you've seen an Internet ad for capacitor-type power factor correction devices, you might be led to believe that using one can save you money on your residential electricity bill. However, a team including specialists at the National Institute of Standards and Technology (NIST) have recently explained why the devices actually provide no savings by discussing the underlying physics".
And last, but not least at all, have a look at what Chris of MapAWatt has to say on the subject!
If this article has helped you please "join our community" to receive your FREE subscription to One Watt at a Time. The Smart Energy updates we send will keep you (the consumers) informed about new ways to save energy.
If you are concerned about the amount of electricity being used by a heat pump or air conditioner motor, the best way to save energy is by installing a smart thermostat and one of the energy control systems included in our directory.
All power factor correction technologies claim to reduce your electricity bill by using capacitors to correct/optimize the power factor of the electricity being consumed in your home. They claim that an improved power factor will help electrical motors run more efficiently, extend the life of electrical appliances, save light bulbs and eliminate static interference.
There is truth in the fact that our homes have devices which consume electricity at reduced power factors. As an example we know that "CFL light bulbs" have a Power factor of between 55% and 70%, while incandescent light bulbs have a power factor of 100%. All electric motors, including fridges, air conditioners, fans and computers generate reactive power which will affect a circuits power factor.
Based on the above information it could sound logical that a pfc technology would save money for a home owner. But this is NOT a correct conclusion at all. Improving a consumers power factor will mostly save a "negligible" amount of electricity. I have correct my earlier opinion of "NO saving" to "usually negligible" thanks to an informative discussion with the founder of V-Blox Mr David Mulvaney.
Mr Mulvaney contacted me regarding his company and said "I want you to know we do not recommend power factor correction in homes and I will be the first to tell you that savings if any would be negligible". Noticing that his company is on a list of "imitation KVAR products" published by a KVAR distributor, I listened to his version of the story. I will be writing a separate posting on how it seems that the real pfc scams have developed. I did find all he said to be professional and reasonable.
Mr Steve Fish, CEO of KVAR Energy Savings Inc. also contacted me. He said "we are a professional organization and will take back any KVAR product that fails to reduce the electricity bill by less than our guarantee of 6%". According to KVAR, they capture and store the reactive power (var's) generated by an electric motors while it runs. We have agreed to conduct tests with KVAR to quantify any reduction in electricity by storing these "captured" vars in a capacitor, and serving them to the motors when required.
There is clearly an issue here, and both CEO's did acknowledge that their resellers were capable of "overzealous selling" - I suggest that all consumers be vigilant when investigating "var" or KVAR related savings in their home.
Power Factor is one of those subjects about which there seems to be a great deal of confusion and many misconceptions. The culprit is the the assertion that power factor = cos(Phi), Phi being the phase shift between voltage and current. While this is true under certain ideal conditions, there are many real-world instances where it is quite incorrect. This article will give you a basic introduction into power factor, and explain why cos(Phi) is not the whole answer.
Figure 1 shows the waveforms for this experiment. The top blue waveform is sinusoidal voltage. The voltage is 1V rms giving a peak voltage of 1.414V, The red waveform is the current. It is 1A rms, 1.414A peak. (If you are awake you will deduce that the resistor is 1Ohm). The green waveform is the instantaneous power, i.e. the product of voltage and current from moment to moment.
At the left hand vertical line the voltage and current are both at their peaks, so the power instantaneous power is: 1.414V * 1.414A = 2W
At the right hand vertical line we are at the negative peaks of voltage and current, so the instantaneous power is: -1.414V * -1.414A = 2W
It should not take too much imagination to see that the average of the power waveform is 1W.
Please follow this link for the complete article titled Power Factor: Dissipating the Myths published by David Stonier-Gibson of SPLat Controls. We thank him for the permission to publish this introduction!
When the power factor is less than 100% it means that there is a phase shift between voltage and current. Consumer tariffs are based on Real Power, only the electricity actually consumed by a device. The consumer electrical tariffs include provision for the losses which this "phase shift" might cause the electricity supplier.
It is true that electricity suppliers need to manage their distribution networks, and that power factor IS one of the factors that impacts their distribution losses. It is also true that large industrial users are charged a penalty for a net power factor of less than 85%. But distribution losses will not be solved by consumers. They are aggregate issues that can only be solved by the utility companies "the smart grid" in partnership with industry and device manufacturers.
Power factor and power factor correction are indeed subjects that we should be aware of, but it is "near fraud" when excessively marketed to home owners as a way to save money on their electricity bill.
We have an overview on "Power Factor" and the definitions for real power, apparent power and reactive power for those who would like to understand more of the technical details on this topic.
One of the most disheartening aspects of all these scams is the amount of money the perpetrators seem to have for promoting and advertising them. As an open source publisher, dependent on contributions and advertising to pay our way, there is little more frustrating to me than the way Google is being abused to promote these scams. I understand that there is little they can actually do about it, for they are not the internet value police, and imagine how we would feel if they did make value judgments on our content.
I believe the answer is for us publishers to block all adverts from these scam domains. And for our readers to value our content with your visits, comments and links. Think of reading these pages as being a part of a virtual internet energy scam watch, where you can help expose their theft and send it to the black hole of "never seen" internet search results.
If you are uncertain as to the accuracy of open4energy's opinion we suggest you review this study by ScienceDaily - (Dec. 18, 2009)
"If you've seen an Internet ad for capacitor-type power factor correction devices, you might be led to believe that using one can save you money on your residential electricity bill. However, a team including specialists at the National Institute of Standards and Technology (NIST) have recently explained why the devices actually provide no savings by discussing the underlying physics".
And last, but not least at all, have a look at what Chris of MapAWatt has to say on the subject!
