EEVblog #1191 - Digital Energy Savers BUSTED!

Digital energy saver boxes that claim to reduce your power bill by up to 50%, are...
SPOILER ALERT:
Complete bullshit.

#EnergySaver #Scam #Debunking

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[stuartmcconnachie]

1:40 earning money, yeah right! The only people earning money are the fraudsters selling this wooo!

4:14 NOT 25 hundred, 25 THOUSAND WATTS!

[bigclivedotcom]

If you guys want to build your own the keywords for the miracle capacitor on eBay are 3uf fan capacitor. Target price around $2 each. Maybe add a couple of 470K resistors in series across it to avoid zings.

[stonent]

Big Clive determined that a hot dog has a power factor of 1.

[johncundiss]

I went to the mass merchant and bought some spark plugs, save me 30 percent of gas. I bought some new special oil for the engine, save me 30 percent on gas. I got some new tires that give good life and save 20 percent of gas. I put a gasoline magnet on my fuel line to save me 30 percent of gas. I was driving around the other day and my gas tank overflowed.

[brandonupchurch]

Only digital energy saver is a Kill-A-Watts meter use it on your biggest energy hogging devices and once you see how much power it actually uses you'll learn to turn it off when it's not in use.

[abysspegasusgaming]

At least hotdogs have a power factor of 1...

[PhilipLeitch]

DEFCON 5 = everything is fine, stand down.

[andrewevanoff]

I'm an industrial electrical engineer. Majority of manufacturing plants are paying their electrical bills in kWH, so power factor makes little difference on the electrical bill. We prefer to keep it above 0.8 or so. Poor power factor may overload the wiring if loaded heavily. We do use power factor correction capacitor banks on medium voltage (4, 160V) motors only.
Beware of "snake oil" salesmen who want to sell you a miracle device that will guarantee at least 20% power saving. Ask them to leave and to never come back! They will sell you a grossly overpriced surge surge protector that does nothing to reduce power consumption. I've seen industrial plants with $800 surge protectors installed at their main substation. They paid $25, 000 for the device and were promised tremendous savings. Problem is that it's very hard to verify the savings due to large variations in production schedule and machine utilization. The salesman who sold them the miracle device, drove a brand new Mercedes. LOL.

[Jonesax]

I saved 10% on the energy of my electric shower with no device at all. Just cut my bath from 10 min to 9 min. Amazing!

[czarzenana]

Don't throw away the thing.
You could still use the metal casing and other parts for other projects.

[emperorSbraz]

in italy you don't only get charged for pfc but also get fined if out of spec.
legends say small factories just eat the fines as it's cheaper than upgrade the power banks. :D

[TMS]

"save up to 35%". "up to" includes 0.

[zox]

1st thing we learned in technical school .... "every conductive part of the case must be properly grounded"... even for a woo woo device no one should get shocked because of poor design ...

[pomodorino]

Just checked, in Italy you don't pay for reactive/capacitive power unless you have a contract for 16.5kw or more.
In the UK only commercial activities are charged, EDF charges for reactive power only if it exceeds 33% of real kWh in the bill.

[_paulgoldschmidt]

Greetings from Germany guys (I totally renounce from this product :D)

[Rob]

Originally "power factor" just meant "cos phi", the cosine of the angle between voltage and current.
Traditional inductive loads had a lower power factor and could be corrected by adding a capacitor.

However, modern devices like your scope are not an "inductive load", the power factor is not low because of angle between voltage and current, but because of non-sinusoidal current. Mostly due to switch-mode power supply without active PFC.

Unfortunately regulations on power metering not necessarily have been kept up-to-date w.r.t. this "new situation".
Try to lookup the requirements of power meters in Australia, you may find that it says nothing about measuring power in the case of non-sinusoidal current. Here in Europe it doesn't. It only mentions "cos phi" and "taking effective value" without any specification on how that is to be done.

So in theory a power meter could be measuring sqrt(2)*Ipeak to get Ieff and would still be compliant.
And you as a customer would pay a lot more for the power consumption by such devices than for power dissipated in a resistive load.
And when you think your bill is excessive, the company will offer you "calibration of the meter" (at your cost when it turns out to be correct), and they will measure it with a resistive load and maybe some capacitive and inductive component, it will come out correct, and you lose.

In reality it often is not as dramatic as sqrt(2)*Ipeak, but it will do some form of RMS metering with a limited bandwidth.
That can still indicate too high when your load has very spikey current. Which a modern electronic device can have.

So you could actually "save power" (not really save power, but cut down on your electricity bill) when you filter the current to your devices in such a way that those current spikes are no longer present and the meter does not see them.
A low-pass filter on the mains should do that. And in fact, such a lone capacitor would act as a low-pass filter, but not a very effective one.
Likely more effective is a big tuned circuit at 50/60Hz. And of course you have to be careful not to incur a lot of losses in there, especially idle load. It could be more than what you save by the improved metering.

[Orbis]

Still a better input protection than Weller....

[williamsquires]

At least it gives you a nice project box that has a hole pre-made in case you want your own project to have a display - oh, and save the line cord and the fuse holder! Plus they give you an AC voltmeter, to boot! Too bad there was no actual magic woo-woo inside... 😫

[morgueaunne]

Clearly, by the packaging alone, you can tell that this is a superior product.

[lolaa]

98kW on 240v is 408A !!!!
I would love to see those tiny PCB traces with 408A flowing thru :-p
Protective googles mandatory ;c)