Which Smart Energy Monitor Is Right For You? ShellyEM vs Sense

today on the hookup we're gonna take a look at smart home energy monitors specifically the $65 shell EEM and the $300 cents energy monitor will cover installation set up and use and then we'll decide whether or not they are a worthwhile addition to your smart house the two products we're gonna be looking at today are the sense energy monitor which retails for three hundred dollars and the shell EEM which costs 75 percent less at around $65 us on the surface these devices are very similar they're both Wi-Fi devices that use a pair of CTS or current transformers to determine the energy usage in your home first you might want to know how an energy monitor even works when electrons travel through a wire they generate a magnetic field around them that has a strength that's proportional to the amperage or the number of electrons that are flowing through that circuit when you clamp a split-core transformer around a wire carrying an AC current the magnetic field that it generates then induces a voltage in a coil in the CT since the strength of the magnetic field is proportional to the current the induced voltage in the CT is also proportional and that allows you to accurately calculate the amount of current running through the circuit once you know the current or the amperage all you need to do is have a reference voltage in the circuit and then you can calculate power both the shell EEM and the sense energy monitor use this same technology to monitor your power but the similarities pretty much end there the first noticeable difference comes when you place your order for the shell EEM on the product page you'll need to select what current rating you want for your CTS this is because the shell EEM is not necessarily meant to be a whole home monitoring solution but instead it's meant to measure just a couple of circuits or even just a single device like an electric dryer that would pull a little too much amperage then you should put through a smart plug in my case I'll be using the shell EEM to monitor the energy usage of my pool by installing it in my pool sub panel and since that sub panel draws well under a hundred total amps the two 50 amp CTS will be fine for me the sense on the other hand only has one option for CTS and that's for good reason the sense only has one intended use and that's to be installed as a whole home energy monitor and that doesn't mean that the sense can't monitor individual devices though it just means that it does it in a really tricky way the sense measures each leg of your service wires separately and it can measure things like reactive power true power and apparent power after that it uses fancy computer magic to match what they call the energy signature of your device to their huge database of energy usage that they've been able to collect from their cloud user base most of the large appliances in your home have these telltale signs that will allow the sense that theoretically recognize them using its cloud-based machine learning platform in practice however I've had my sense installed for just over a month now and it's found 10 total devices seven of which it guessed correctly and three of which I haven't actually figured out what they are but it's definitely not what the sense guessed there are a few large items in my house that I figured the sense would easily be able to find but it hasn't yet specifically I have two separate AC units one for the first floor and one for the second floor sense was able to locate my first floor AC unit within the first three days but it still hasn't found my second floor unit similarly it's also located my garage refrigerator but it hasn't located my kitchen refrigerator it also hasn't been able to locate my pool pump or my pool heater which are two of the primary devices that I was hoping to monitor the installations of both of these devices are pretty simple but they could be and maybe they should be terrifying for someone who hasn't done work inside an electrical panel before I know I've cautioned you in the past that working on mains voltage and your outlets is dangerous but this takes it to a whole new level even after you flip the main breaker on your panel the service wires are still live there's no GFCI or circuit breaker to save you here if you complete the circuit between these wires with your body very bad things are gonna happen if you aren't comfortable with electricity I'd highly recommend that you get a certified electrician to do these installs for you in fact the documentation for both the sense and the shell EEM suggests multiple times that the installation should be done by an electrician moral of the story please be careful and if you feel like you might be over your head just don't mess with it in the u.s. we use something that's called split phase electricity this means that we have to supply lines coming to our electrical panel and both of them are 120 volts ac but there are a hundred and eighty degrees out of phase from one another this means that if you reference one of them to the neutral you're gonna end up with a hundred and twenty volts ac but if you reference them to each other you're gonna get 240 volts of potential because each rail your supply doesn't necessarily have the exact same voltage you'll need to provide the sense with three electrical connections to 120 volt connections in a neutral connection since it's generally bad practice to have more than one set of wires connected to each breaker I installed a new 240 volt breaker in my sub panel to power the sense after you've connected the sense to power you'll plug the CTS into the main unit push the external antenna through one of the punch outs in the breaker panel and then last you'll clamp the CTS around your supply lines you should never clamp a CT around a supply line without first closing the circuit by connecting it to your device doing so will induce voltage in the open circuit and that's dangerous because it can arc through the connection once all the wires are in place you flip the breaker back on and you'll hear the sense make some musical sounds signifying then it's ready for setup the setup process is pretty typical and it just asks you for some personal information like your name email and phone number and then you're all done installing the shell EEM is less straightforward but it's still not difficult by any means if you've wrapped your head around the basic concept if you want to measure a single 240 volt circuit with a shell EEM you're gonna need to provide it with a 240 volt reference as i mentioned before it's bad practice to hook up more than one wire to a single breaker so to install the shell EEM in your breaker panel you're gonna need to install a new 240 volt breaker and then hook up one of the 120 volt lines to the L terminal on the shell EEM and the other 120 volt line to the N terminal you'll then install a single C T around one of the wires coming off of your 240 volt breaker since the e/m has connection for two cts you could actually measure a second 240 volt breaker using this method if you want to measure 120 volt circuit you're gonna need to provide the Shelly with 120 volt reference this means instead of using the new 240 volt breaker you'll instead use a 120 volt breaker you'll also want to make sure that this breaker is on the same phase as the circuit that you want to monitor otherwise you're going to get some interactor at measurements because your reference voltage could be different than the circuit that you're measuring in either case just as before you want to make sure that your CTS are connected to your Shelly and not in an open circuit when you install them on your wires for both of these use cases the Shelly M does a fine job measuring current draw but for me I wanted to measure the power consumption of my entire pool including the lights pump chlorine generator and heater to do this I needed to be able to measure both of the supply lines in this sub panel each of which is 120 volts some of the circuits in this panel are 120 volts and some are 240 volts so it's not sufficient for me to have a single CT around one of the supply lines since I then wouldn't be able to see the 120 volt circuits in the other phase the problem with this setup is I need to give the shell EEM 120 volt reference for it to accurately measure each of the supply wires but that causes two issues first this can lead to some inaccuracies in the power calculation since power is calculated by multiplying amps by volts and even though the amperage is going to be correctly measured the voltage is only measured on one of the supply lines so if there's a significant difference between the two my power measurements won't reflect that for my particular system my two rails are never more than a few tenths of a volt different from each other so it's not a big deal for me but depending on your power grid where you live it could cause a problem the second problem is that if I install the CTS in the direction shown on the plastic it's gonna give me one positive value and one negative value this is because the supplies are 180 degrees out of phase from one another so the reference voltage is always out of phase from one of the CTS luckily the fix for this is really simple all you need to do is flip around the CT that's showing a negative voltage in order to make it start showing a positive voltage now that our devices are installed let's take a look at the apps and what we can do with the data the sense app is pretty neat and it seems really well-made the bubbles on the main page put the energy consumption of each device into perspective and on the devices tab it gives you the ability to create notifications for when a device turns on or off you could easily use this function to do things like notifying you when the washer is done in your clothes need to be transferred into the dryer that is of course assuming that the sense has discovered your devices and that in my opinion is the biggest downfall of the sense I'm not sure why they haven't implemented a system to speed up discovery where you maybe tell it which device you want to discover and then flip that device on and off a few times but that option just isn't there it boggles my mind that there's a chance that you're gonna buy this $300 energy monitor mount very particular device in your house and that device could never be discovered I know for instance that a few of the energy hogs in my house will never be discovered because I go to great lengths to make sure that they never turn off or lose power this includes all of my networking equipment my home assistant Plex and blue iris server and my personal PC I'd love to be able to tell the sense that I have an always-on type device and then switch it on or off a few times for the sense to learn its power consumption and then have it keep track but as I mentioned that's just not part of what the sense can do for the shell EEM you'll use the Shelly app and as always in the Shelly app you have two different options you can either connect to their cloud server and store historical data on their servers and control your devices from anywhere or you can disable the cloud completely and use local MQTT to integrate the shell EEM into your home automation platform of choice I will of course be doing the latter but let's take a look at what's possible in the app using the cloud connection first when using the cloud the Shelly M monitors power over time and it has a similar overview page to show the total consumption being monitored by the Shelly devices you can use the scenes tab to create similar automations for the washer and dryer as long as that's the circuit that the Shelly e/m is connected to but it's definitely not quite as straightforward as the sense app as far as app integration goes I think the sense app is overall a better energy monitoring app but the Shelly app also has the benefit of controlling all your other Shelly devices this allows you to have one device communicate with another and you can create scenes and automations directly within the app but if you've watched my channel before you know that I don't really use separate apps and I'm always going to try to integrate everything into my home assistant hub so next let's see what it takes to get these two things into house IO the sense integration is really simple you just add three lines to your configuration yellow file and it links your home assistant to your sense cloud account the sense integration uses cloud pulling meaning the sense is going to communicate directly with the cloud and then you're going to pull that information from the cloud to your home assistant it's unfortunate that there's no local polling option but it's really not a deal-breaker for me because in this case the sense is a non critical device after adding those lines to your configuration file a quick restart in the sense integration will add a binary sensor for each device that is discovered and then also a sensor for your total energy consumption and then your daily weekly and monthly consumption using the binary sensors you can easily create automations based on your discovered devices but ultimately that goes back to my big issue with the sense which is that you are completely dependent on your sense discovering your devices and there's no guarantee for a time frame when a device discovery will occur or even that the device will be discovered at all still the sense integration was one of the more headache-free experiences I've ever had having a cloud only device to home assistant integrating the shell EEM into home assistant will utilize MQTT so first you'll need to turn on MQTT by going to the web console of the device then selecting internet and security and finally advanced developer options where you can enter your MQTT broker information when you turn on MQTT the Shelly cloud connection will be disabled but since you're integrating into home assistant you probably don't care about that anyways according to the documentation the Shelly publishes messages on all of these topics but in my testing I found that only the power and voltage topics were actually being used I suspect these are going to be used in later firmwares but these topics are currently not in use I'm mostly interested in the instantaneous power messages for the two channels on the Shelly e/m so to get those values into home assistant I'll add an MQTT sensor for each value and then I'll include the specific and qtt topic for each value under the state topic remembering to modify the device ID field with my personal Shelly's device ID and then I'll modify the I filled with the channel number of the CT that I'm measuring because I'm measuring the current draw of my entire pool sub panel I also want to include a combined value for energy usage and power to do this I'll just add a template sensor to combine the values of the individual channels then I hit save check and fig and then after the restart my new sensor should be there ready for me to add to the lovelace interface if you want to correlate this to a device like the fancy machine learning in the sense you're gonna have to do a little detective work first to do this monitor your power consumption and turn each individual device on and off record those values on a scratch sheet of paper and also try to determine if you have any idle power consumption caused by always-on devices since I don't have a fancy machine learning setup I'm gonna use node-red to specify my devices I've posted some clever code down in the description that allows you to determine which devices are contributing to the overall power consumption value by entering an array of wattage of your devices there's also a tolerance for power fluctuation and an idle power consumption value for when all of your devices are off I'm also using some logic that's specific to my circuit to determine the difference between 240 volt devices like my pump heater and salt generator and my 120 volt devices like my pool lights and my patio speakers if you want an explanation of what the code actually does I might post a quick video later on but you don't really need to understand how it works in order for it to work for you here you can see that by monitoring the total power of the system I'm able to extrapolate the state of each of my connected devices fairly accurately keep in mind that the more devices you attempt to monitor and the more similar those devices the less accurate this system will be if you see that your devices are being incorrectly identified you can try lowering the tolerance value in the function node if no results are being given try raising that tolerance I don't know if I would use these device States for any critical automation but they're surprisingly accurate for being such a blunt tool once Shelly adds the topics for reactive power it's going to be even easier to differentiate between the devices on the same circuit but for now this is working well for me and the best part about the Shelly solution is that you aren't at the whim of the sense machine learning algorithm to discover your devices that you want to monitor with this system you can install it and be monitoring and automating on the same day so which energy monitor should you get well the sense is a really high quality product and I think it's a great choice for a lot of people I think it's even pretty fairly priced given the hardware cloud integrations storage and machine learning algorithms but for $300 I'm pretty disappointed that it has only discovered a handful of devices over the course of a month and with only about 70 percent accuracy only time will tell how useful the scents will be and how many devices it will discover but for now it isn't super helpful to know how many times a day the microwave or ice maker has on or off for me the shell EEM is much more my style mqtt local control allows me to manipulate and use the data as I see fit and the price is certainly right at just $65 ultimately when choosing an energy monitor you're gonna need to decide for yourself how much legwork you want to do if you just want to plug it in and have it work eventually the sense is probably for you but if you want full control you should go with the shell EEM thank you so much to my awesome patrons over at patreon for continuing to support my channel if you're interested in supporting my channel please check out the links down in the description if you enjoyed this video please consider subscribing and as always thanks for watching the hook-up [Music]

Channel: The Hook Up

Views: 236,156

Keywords: home assistant, hassio, home automation, hass.io, smart home, diy, electronics, arduino, esp8266, nodemcu, wemos d1, automation, ShellyEM, energy monitor, energy, usage, sense, smart, meter, energy meter, power, consumption, wifi, cheap, mqtt, shelly, CT, node-red, node red

Id: 5RyDxZLA8b8

Length: 16min 38sec (998 seconds)

Published: Wed Sep 11 2019