Electricity Outlet Monitoring

From w.mfi

There are expensive smart home outlet monitoring devices, and there are super-simple "plug'em in" devices. This page covers the latter.

The bottom line here is that they summate energy usage over time. While it's nice to see watts, what you really want is to see the total over long periods of time. You can't watch the watt reading forever... you need the device to summate watt-hours for you.

What are they good for?

These units plug into the wall, then you plug something into them that you want to monitor.

Actually you'll want to plug them into an extension cord, because they're hard to read if stuck to a low-down outlet. This isn't really their bad; did we want them to guess our cord length/situation? Anyway: Mine have a dedicated cord.

Sometimes they reveal big power drains. I found that a $210 Frigidaire 70-Pint Dehumidifier (Model FAD704DWD) was using about $240/year in electricity, dehumidifying our basement. That's some serious cash, and I had even made a point of getting an Energy Star model! Other dehumidifiers may do much worse.

Nobody ever warned me about this, and we only barely needed the dehumidifier... the humidity was not that high (65% in summer), plus its energy use is probably low for a dehumidifier, being Energy-Star rated.

But wouldn't you want to know if something costs hundreds or thousands more every single year past what you paid for it?

I was also able to show that a refrigerator of ours was going bad, using much more energy than it should. This is a problem with self-regulating devices... a real issue can be hidden by them working harder to overcome the problem. The frig was on about three times as much as it should. It was not a trivial problem.

Otherwise, they let you know if laptops, TVs, and anything else uses much power in its standby mode. Sometimes you are pleasantly surprised. Sometimes not. (If you want to easily turn things completely off, consider a $30 set of cheap remote-control outlets.)

A backgrounder on me and outlet monitors, if you care

I first started in 2009 with a simple P3 Electronics P4400 Kill-A-Watt meter. It cost $22 at the time and was nice in its way, but very basic.

Then I moved up to a P3 Kill-A-Watt P4480 GT, $35 on Amazon in 2013

I loved these guys over the simple P4400 because, for one thing, they gave another decimal on power usage ("1.0 watts", not just "1 watt"). But they fixated on controlling power by time of day and much of their display centered around this. I only wanted more info on energy usage.

Eventually they crapped out circa 2015. The P4480 was no longer offered, so I got two P4482 "Control" units in November 2015, but I found they kept having overvoltage errors. This means they stop recording anything and shut down, but I knew my house voltage was fine, not overly high.

In a stunt of buffoonery, when I called P3 Electronics about it, the rep went back and forth talking about how my house's electricity may have gotten too high, and I really need to talk to my electricity provider (because it can't possibly be their fault), but when I pointed out to him that the overvoltage errors were occurring even within the specs laid out in the manual for this device (it said it wouldn't give an overvoltage until 135 V but it was giving them at 124.4), he caved and reluctantly agreed to RMA, in which case I got two more P4482s ... which were also defective in this regard.

So I write off Kill-A-Watt as a respectable company, and don't recommend them. It's unacceptable when a rep knows that the overvoltage you are talking about should not happen for that device, but he doesn't want to RMA unless you have the wits to point out that he's contradicting their own design specs. I can only surmise that a good engineer designed these things, but the factory didn't make them right, and the company (and support) otherwise crumpled.

Recommendation: The Floureon TS-838

I tried the Ensupra Monitor ($20 on Amazon; it doesn't have a model number, sigh) and the Floureon TS-838 (also currently $20 on Amazon).

I recommend the Floureon. It's been a year since I worked closely with these two (I use smart-home monitoring more now). They're very similar; they probably both use the same basic chips and factory. I just remember the Floureon's info worked better for me. I have no reason to doubt either one's accuracy; I don't have any other sophisticated instruments to check either of them.

"Floureon" is a dumb name. Is it flour? Or is it a misspelling of fluorescent?

If anyone knows of some better device, please drop me a contact!


I am only interested in these guys for energy monitoring. If you want to get another decimal point of accuracy out of them, play with your energy cost. I can't remember the details but it's something like, if you tell it your cost is 9.99 dollars per kWh, it will then show you your energy usage with another decimal of accuracy, when you look at your rigged cost.

Sorry for the lack of details but I go through a lot of devices. If you study your device, this tip will make sense.

A Plea To Engineers Making Outlet Monitors

We - or at least I - just want energy usage data!

  • Someone make something that doesn't devote most of its screen space to the time of day and time of week, for controlling a device over time. I don't want a controller, I want an energy monitor.
  • Someone make something that goes very low with energy monitoring. Milliwatts, and watt-hours. Please stop with all the super huge kilowatt measures... we want to know just how small some vampire devices might be.
  • Please drop the stupid kg CO2 measures, and what not. Kg CO2 is a super simple calc anyone can do any time given your totals. Your purpose is to show energy usage. Let's compromise: Just make a screen that simply says "almost infinitesmal kg CO2 for anything you can plug in", then let users opt to never show it, and leave it at that. K?