a Device that stores reactive energy, savings of 10-12%?

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Old 02-09-07, 11:00 PM
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a Device that stores reactive energy, savings of 10-12%?

Hey guyz,

Ive been reading up on this device that supposedly stores energy (reactive energy) until your home appliances (especially ones with motors or compressors) require it. Sounds like a giant capacitor in a box on stanby to me. I was thinking of hooking it up to my old 10 SEER CAC condensor unit that just takes a chunk out of my wallet every summer. I wouldn't really connect it to my whole house since it's fairly new and might break down. Has anyone ever owned such a device? Suggestions and comments are welcomed.
 
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Old 02-10-07, 01:14 AM
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Give us a link?
 
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Old 02-10-07, 03:07 AM
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KVAR inc.
http://www.kvarnrg.com

GE co. makes a similar device called POvar
http://www.gepowercontrols.com/10086/10164/10166/index.html?SMSESSION=NO

I researched these two and they claim to do just more than save 10-12% on utility, they also claim that the device actually prolongs household appliances' life and relieves strain on household electrical wiring too by reducing heat build-up etc...
 
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Old 02-10-07, 04:26 AM
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http://www.electrical-contractor.net/ubb/forum1/html/007919.html

that is a link to a website that deals with the electrical industry. If you read the thread, take note of a poster named "WFO". His info would give you the answers concerning the device youspeak of which appears to be a simple power factor correction capacitor along with possible a surge supressor added on.

If you take a look at the meter on your house, you should be able to see if it is a KwH or KvaH meter. Chances are it is a KwH meter and power factor does not affect the measurement it indicates.



Did anybody see a price for this little gadget. My elec bill is about $100/month. If I achieved a 15% savings, that would be (ta da) $15 per month. I would like to figure out what their claimed savings would require as payback time to pay for the gadget.
 
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Old 02-10-07, 04:50 AM
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And it says..

"Savings in Demand charges (KVA)
Eliminating low Power factor penalties."

I'm charged by how much power I use, not how fast or efficiently I use it, as a large commercial enterprise would be.
 
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Old 02-10-07, 07:58 AM
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Don't know much about them. A few years back,I did see them at the big box stores, About $40. They disapeard as fast as they arrived . The trend lasted about 3 months, have'nt been seen since.
 
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Old 02-10-07, 09:09 AM
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At work we are surchaged for power factor issues and are presently working on a plan to eliminate the problems. A homeowner shouldn't even be worried about it.
 
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Old 02-11-07, 06:40 PM
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payback

the payoff was what concerned me the most also. This device goes for around 400 dollars with just a 5 year manufacturer's warranty...which pretty much means "good luck trying to use this after 5 years+" lol. so at most 15% savings for 5 years (assuming a regular 100 dollar electric bill) would account for only 500 dollars overall savings in 5 years. Also considering the time spent yourself or paying some1 to install this thing in the first place and removing it when it breaks down, I say it's just not worth the trouble. 99% of residential meters don't even take power factor into account which this device provides, so it clearly isn't worth it.

And nap ur right, I have a KWH meter and it does not take into account the Power factor just as WFO stated in your link.

I just have to quote this from your link I found it very humorous but practical: "walrus: Every house I've ever been in has a power saving device, its called a switch, use it and save"
 

Last edited by kamrandiaz; 02-11-07 at 06:51 PM.
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Old 02-11-07, 06:52 PM
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and that is based upon numbers IF it performs as suggested, which I have serious doubts of.

If it were truly beneficial, I would think more companies would be offering the devices. Not always the defining factor but often a good indicator.
 
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Old 02-12-07, 08:39 AM
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There have been a few threads on this board and on other more professional forums, and the general consensus is that reactive power management and power factor correction yield no savings in residential buildings.

The primary reason for this is that residential electrical (kWH) meters do not measure reactive power. Therefore the only cost savings a residential customer can realize are those which come from minimizing a type of heat loss called I-squared-X losses (I^2 * X) by slightly reducing the current (I) through a motor's branch circuit; the reactance (X) of the wiring is primarily a function of conductor length, and residential branch circuits simply aren't very long. Furthermore, many (but not all) appliance motors already have run capacitors properly sized to match the motor.

Commercial buildings are a completely different story because the power company does meter reactive power at those locations, and there are substantial surcharges for excessive reactive consumption.
 
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Old 02-14-07, 05:39 PM
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Here's the thing that gets overlooked. There are two types of reactive power, inductive and capacitive. In a purely inductive circuit, the current lags the voltage by 90 degrees; in a purely capacitive circuit, the current leads the voltage by 90 degrees.

But they both require reactive vars! So this little device sitting there with it's overpriced capacitor will draw reactive current all by itself anytime there is no inductive load on.

Net result....if you're sitting there with nothing on but resistive elements (water heater, incandescent bulbs, strip heat, etc.) the capacitor is actually making your power factor worse.

Ideally, the capacitor would only switch on when there was a matched inductive load that it could compensate for.

But I bet it doesn't.......
 
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Old 02-15-07, 08:18 AM
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Concur. These are must-haves for commercial and larger multi-housing such as highrise where there are lots of motors, but the solution does not scale down.

A plant manager I spoke with said the installations, including commercial electrician labor, paid for themselves in one month in one building and two or three months in five other buildings. These are places where the bills run around $100,000 a month, though.
 
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