How Much Juice is that Laser Using?

I just got this tool (toy?) delivered. It’s a whole house energy monitoring unit. It looks like it has a pretty good pedigree, but we’ll see how well it works once I get it installed. It cost $299. If it works as well as presented, it will be helpful (fun?) to have around the house. Has anyone else had an experience with it?


Amazing if it works.

Would be interesting im feeling some degree of snake oil. It works by Listing to the back feed noise patterns of your appliance (those things the fcc tests for and will block sale of if to noisey). And thing it would be i treating what it does about devices on ups or power cleaners

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I have/had an old version of this kind of thing. (It’s still installed, but the part that receives the transmissions is borked.) The basic functionality is pretty good. And my guess is that recognizing appliances isn’t that hard, because the power draw alone would narrow the search substantially. (Mine was of a time before big data, so you had to go into the history and tell it which appliances were which, and I never bothered because for the most part, duh.)

So at a minimum you’ll be able to just go into the graphs and see what happens when the laser is on vs when it’s off.

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Looks neat. I’m especially interested if it works well without smart appliances. I’m continually getting emails from my power company that I use more electric than my neighbors. I’d like to know what’s doing it. My direct neighbor is no help because they live in the dark. I’ve not seen more than one light on in their house at a time since their kid went to college. My last one did this fall and my bill dropped by 25% but it’s still more than the rest of the neighborhood.

Thought it might be the meter but it’s an old school one - not one of the digital ones that our electric company has had accuracy issues with.


Please keep us updated with its performance.

Since I work out of my house, I would be interested in how it works over a week and then a month.

I have 3 to 4 servers, 8+ desktops, 4 laptops and way to many IoT and mobile devices that I would like to get real time data and power logs for.

for anyone looking for something more affordable, these kill-a-watts work extremely well at checking one plug at a time, and at less than 20USD, it’s hard to beat:


Hopefully you have so many GF projects that it affects your electric bill. More likely Fridge/Freezer/Wash/Oven/HVAC and lighting are so huge that it’s really not a thing. We switched our entire house to LED lighting, and just changed out our HVAC to super efficient, and it practically halved our bill (well, what would be our usage if we didn’t have solar, which makes it super hard to actually determine)


I hope to get it up and running in a week or so. It does look like there is a learning curve for the device. One other issue I read about is that it has trouble combining different draws from components within the same device. An example is a dishwasher with a pump, heater, etc. It would recognize each electrical signature as separate items within the dishwasher. I don’t know if those could be consolidated into a single group entry at this time.

I do like the fact that you can manually name a device if you can isolate a draw that it doesn’t easily recognize. That also helps for multiples of the same device. For instance, as I understand it, it should recognize multiple TVs as different devices. It wouldn’t know where the TV is, but you could turn the Kid’s TV on and when it registers, name it so you can differentiate it from the living room TV.

Overall, it seems like it will be interesting to work with it while waiting for the GF delivery. That’s why my original post identified it as a “tool (toy?)”. Most likely it will initially be something to play with rather than a true money saving tool.


Have one of those (Kill A Watt). From Harbor Freight. Poor boys do what they can.

Though I notice the current price at Harbor Freight is much higher than what I paid.


Me too – After checking that a device isn’t rated beyond the K-a-W’s capacity, I check new devices individually for about a month to get a sense of usage over time. For example, it costs me about $1 in electricity to print one e-Nable hand on my UM2+ 3D printer.


Ok…you get this information about appliance electrical usage after spending $300, installing it and training it(?). After a couple months of data, then what? I know many baseball fans are as interested in statistics on players as the game itself. I am not a baseball fan… :slight_smile: - Rich


the idea is that then you know how much everything costs to run in a very real way. you can calculate exactly how much your fridge is using over a year and clearly figure whether buying a new one is worthwhile, or whether it makes more sense to cook your food in the toaster oven vs your main oven (quality of cook and end product aside).

i’m curious to see how much it’s going to be able to figure out on its own without any end user training. it’s probably going to be picking up the big ones pretty easily - fridge, furnace, a/c, stove, oven - these all run on predictable cycles that are easy to model.

things like a light switch that dims or controls multiple bulbs, i’d be pretty surprised if it figured that out, since the load may change depending on how it’s being used that day. `

anyway, sure, it’s expensive now, but that cost will come down over time. and it’s much more useful having this sort of granular data local and immediate rather than trying to extrapolate patterns over time from your power bill (if it even gives you sufficiently discrete units of time, which many companies don’t).


Spot on. I have new kitchen appliances but we’re still running an old refrigerator in the basement for overflow food. Also have a really nice plasma TV but maybe it’s time to replace it with an LED even though it’s only a few years old and thousands of $ of sunk cost - the new ones are pretty cheap. Ditto for the washer (dryer is really new, washer is about 10 years old).

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This is what I use on the house now :

On the power usage test I did I used this :

(Well, its not EXACTLY this, but uses the same chipset)

Now the HA system I use :

Any two of the devices come up less then that device and you’d get a heap of functionality.

Another other way would be a RPi with a Z Wave ‘HAT’ then poll them that way.

An example use case is me and the wife went on vacation to CA last year. The mother in law stayed home. Both me and her got a push notification @ 3AM EST that the power usage jump up to 4700W and it was a abnormal behavior (as it looks at trends). My wife opened up the app, went to the section that had the kitchen- fired up the security camera app and saw that the oven was on with a pot on it. Then she was able to kill the power (220V) to the oven remotely. That- was worth the price of admission. As that could have gone sideways pretty quickly.


Sure, though I don’t think ease of use should be discounted. You can buy the sense and plug it in and have it go to work. Easier than generating your own baseline model and proceeding thus.

Though I’m tempted to buy one for myself.


I’m told some libraries loan out Kill-A-Watt or similar devices.

Now that I think about it, the number of people on this forum that would borrow a tool that had to be returned instead of buying it is probably fairly low to nonexistent. Well, maybe there is one.


Borrowed a Backhoe once. From my son. Couldn’t afford to buy it, he’s a ruthless negotiator.


ugh just read you cant use a computer or web page to get to it it appears to be app only . I hate that

would be nice if they had a windows universal app


Because 1 - he had a good teacher and 2 - he knows what arguing with Dad will get him.
Seriously, that’s the perfect tool for that task! Soil does’t look too rocky there. Water, propane or utilities for another structure? Nice spread You have there! :+1:

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