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Powersave 1200 1

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bytebyte

Electrical
Sep 25, 2005
32
A customer inquired about using Powersave 1200 to reduce his electric bills by 25%. Has anyone heard of this and know how accurate this device is? Apparently, it just requires plugging in to the breaker panel. Can someone please explain how this device operates and how it is able to reduce the energy bills? Thanks!

 
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Misinformation?? This appears to be a surge suppressor. While this may be a good idea in areas prone to lightning strikes, It won't reduce energy usage.


Bill
--------------------
"Why not the best?"
Jimmy Carter
 
It's bordering on being a scam. The official documentation will contain just enough "weasel words" to avoid prosecution, but in essence, the only way they could save on utility bills is if the utility is charging them significant penalties for poor power factor. It's just a capacitor inside.


"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
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That's funny; I was just reading about TVSS's and saw this thread.

BC Hydro, a provincial Crown corporation here in Canada has some information about these things. It's a scam; if there was a way to get free energy you bet the utility/generator would be doing it. They talk specifically about the "energy savings" claims.

 
It doesn't work as an energy saving device. It's a power factor correction device AKA capacitor.

Watch the demo video - they show that the current is reduced by their device. However, I imagine there are very few if any residential hydro users who get billed for current. The power company bills for power in kW for the vast majority of residential customers.

It is possible to have a fairly high inductive reactive or capacitive reactive current draw on the power system. Your kVA draw will be much higher than your kW draw. However, residential customers do not get billed for kVA so it's irrelevant.

 
My bad. I looked quickly at the specs. I read the supression specs and missed the capacitors.
The last example in the demo video is a little strange.
I am trying to imagine what normal residential loading will draw 8.35 amps at 0.059 PF. The real component of the current works out to about 1/2 amp. Did anyone notice the little minus sign next to the corrected power factor? The power factor has passed unity and gone leading. Most of the 4.36 amps of "corrected" current is reactive and is being drawn by the unit itself, maybe. I say "maybe" because the readings don't seem to reconcile. The calculated real current changes from about 1/2 amp uncorrected to over 4 amps corrected. There should be almost no change in the real component of the current.
This would be an 800% increase in real power as seen by the revenue meter and billed to the customer. Not a good selling point.
Something is very wrong with the demo.

If you buy one of these you will be buying an electrical device from someone with little knowledge of basic electricity and no knowledge of residential power billing practice.

The timing of the marketing is right on. The units will be bought and installed in time for the normal drop in energy consumption in the spring.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
I failed to mention that this is a small commerical customer with a demand meter that measures kVA usages. So the customer is being billed for kVA usage. From reading the replies, this powersave device can lower his utility bills by correcting his power factor; hence reducing his power consumption. This device wouldn't be effective in lowering electric bills unless a customer is being charged for kVA usages. Is this correct?
 
A better thing to do would be to look at the electrical system and see what is causing the demand (kVA) charges, and exactly how the billing is done (average or peak demand).

For example, if most of the customer's kVA comes from a constant load, and the PF is very steady, a passive capacitor might work well to improve PF. However, if the kVA is intermittent (a large motor with lots of starts and stops) then the best solution could be using a VFD to drive the motor instead of a conventional starter.
 
Did anybody realize he was measuring 5.8 Amps on the motor with NO LOAD??? What 1/3 hp motor draws that much without load? It's either a capacitor, or just a hoax . There had to be some hidden load in that first video. Also, you'll notice each time he switches something on, the power factor changes from lag to leading, except on one where it goes from lead to lag. Also as Waross pointed out a pf of .05 lag? Was someone running a giant electromagnet or something? These videos are hiding things. We aren't seeing the whole picture.

------------------------------------------------------------------------
If it is broken, fix it. If it isn't broken, I'll soon fix that.
 
bytebyte said:
... So the customer is being billed for kVA usage. From reading the replies, this powersave device can lower his utility bills by correcting his power factor; hence reducing his power consumption. This device wouldn't be effective in lowering electric bills unless a customer is being charged for kVA usages. Is this correct?

I don't know of any utility that bills ONLY for kVA use. They are billed for kWH, then their bill is adjusted for kVA DEMAND. Demand charges have a time factor in them, usually 15 to 30 minute sliding windows. So as mentioned above, adding a capacitor will have little effect on his demand charges (unless it is one HUGE capacitor?).

And read the above responses more carefully. It will not reduce the power consumption by any appreciable amount. It only reduces the current on the load side of it. But the kW draw from the utility remains the same. There is an incredibly minute amount of reduction in I2R losses in the wiring, but in an average facility with properly sized conductors, those losses are so small as to not even be noticeable on a monthly basis. On one installation I investigated for a light commercial customer with about 8,000 sq. ft.of mostly lighting and HVAC loads, I calculated his I2R savings at roughly $1.20 per year, making his ROI out to about 180 years!

Like I said earlier, these things are scams, or so close to it as to be indistinguishable. They are intended to prey upon the fact that most casual users will not understand the relative complexities of how they pay for energy.


"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> faq731-376
 
Residential charges are usually kW only.
On commercial I have seen kW plus KVA demand.
On industrial I usually see kW plus power factor penalty. In some areas KVA demand charges may be applied monthly or yearly.
Industries that have a seasonal work schedule may be subject to a yearly demand charge.
The points are,
1> You must know the basis of your customers charges before attempting to reduce the charges. You must determine whether the demand charges are based on kW demand or KVA demand.
2> There is a science and an art to power factor correction.
The science on a large system is to use a power factor controller and switched capacitors, or identify the cause of the high demand and correct it at the source.
The art is to determine how many KVARHrs a month are required to bring the power factor above the penalty cutoff. A small bank of capacitors connected 24/7 will go a long way towards bringing up the monthly average power factor. A large motor may be be slightly over compensated so as to add VARs whenever it is running. The art is to avoid a situation where the system is over corrected too much.
3> Capacitors won't do much for a kW demand. That usually needs customer education and an amended operating cycle to effect savings.
4> If the customer is paying a power factor penalty, it is usually more cost effective to do a survey and apply the correct amount of capacity rather than just throwing random amounts of expensive capacitors and snake oil at the problem.

Bill
--------------------
"Why not the best?"
Jimmy Carter
 
I didn't dwell on their "proof". As soon as I saw they were using amp readings on their demo board I stopped watching.

Follow the advice of stephenw22. You have to investigate the reasons for the kVA demand and address them. A canned solution isn't the fix.

 
There was a great paper by Bill Howe of EPRI in this year's IEEE T&D conference proceedings about evaluating exactly this sort of claim about this sort of device. I'll have to dig out the details if anyone's interested, but it's a fairly plain-language paper, maybe the kind of thing to show a client to counter a bad sales pitch.

I'll add that it was funny to watch him give his presentation, and call out TVSS-based energy saving devices as utter crap (not his words), immediately following a presentation by a TVSS device salesman.
 
I for one would love to see that paper, details please. These so-called "energy saver" schemes are a pet peeve of mine, I can't stand those who prey on the innocent and ignorant. Whenever energy costs spike, these kinds of people slither out from under the slimy rocks and rotten logs... After surging in the 70's, then dieing out, the internet has given them a whole new playgound.


"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> faq731-376
 
That's the one.

I hate going to IEEE Xplore to look things up, though, so for those of you that also don't care for Xplore, or just do not have access, the official citation is:

Energy savings from PQ mitigation technologies[:] Techniques for evaluating vendor claims

Howe, B.
EPRI, Palo Alto, CA;

This paper appears in: Transmission and Distribution Conference and Exposition, 2008. T&D. IEEE/PES
Publication Date: 21-24 April 2008
On page(s): 1-5
ISBN: 978-1-4244-1903-6
INSPEC Accession Number: 10024875
Digital Object Identifier: 10.1109/TDC.2008.4517263
Current Version Published: 2008-05-12

 
OK, they have a UL listing for their capacitors.

Doesn't mean it will save energy as they claim. Just means the capacitor won't start a fire.

 
I was asked to verify results of a similar product about 5 years ago. The seller had a portable test setup very similar to the video and showed similar dramatic current reductions.

I looked up some previously completed research on line and apparently a legitimate scientist proved that a large percentage of power may be saved thru capacitive correction of unloaded small motors (I cannot remember the details of the research, but they were not important in leu of next statement). The conclusion of the report was that 100% power savings are achievable by turning off the unloaded motor. The percentage savings were not available on a loaded motor (though power factor correction is a well known science).

The next step after saying I could not verify any theory to support the vendor's claims was to actually install the units at a continuous process plant, on the main power distribution switchgear (this was the vendors recommendation not mine!). I expressed concern about unswitched capacitors being connected to a variable number of motors and possibly causing voltage excursions above nominal during periods of light load. I also expressed concern about the undocumented contents of these magic boxes. The vendor discounted my concerns and claimed the mystery boxes were not capacitors. Installation was completed and there was an "apparent" drop in current at a local switchboard meter. This site was primary metered by the serving utility about 800' away from the switchgear. ABSOLUTELY NO changes in consumption demand or power factor were dicernable on the utility meters with the units switched on or off. This test was continued for several months, eventually the plant asked the vendor to remove the mystery boxes.

We were not funded to verify what was in the boxes nor did I have access to open one up (they were very well sealed).
 
I love it. "Ads by Google" for this page is right now showing an ad for the Power-Save 1200! Probably because it just mines for keyword combinations. I can't copy and paste it, but is says;

"Save 25% on Your Electric Bill. Don't Be Fooled By Imitators!"

LOL.

Doesn't say 25% of your ENERGY, it says 25% of your ELECTRIC BILL. How do they know in advance that I am receiving a 25% PF penalty?

I clicked through. As to it being targeted towards commercial and industrial customers or residential customers in 3rd world countries who sometimes might get PF penalties? I offer the following cut and pasted from their website:

Power-Save Website said:
The Power-Save 1200™ was designed with the homeowner in mind, providing lower energy bills, increased motor and appliance life, for all of the equipment inside of your house.

Residential customers throughout North America could see a realized savings of 8% - 10% typically and as much as 25% on their electrical usage (and thus power bills).
I added the emphasis, but I have NEVER heard of a single utility in North America who charges residential customers for power factor. This shows me that these guys are truly attempting to scam homeowners. They should be brought to the attention of the FTC, this is an obvious attempt to take advantage of the average homeowner's ignorance about electrical billing.


"If I had eight hours to chop down a tree, I'd spend six sharpening my axe." -- Abraham Lincoln
For the best use of Eng-Tips, please click here -> faq731-376
 
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