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Energy Monitoring (with Home Automation)

Linwood

Active Member
Is anyone doing per-circuit energy monitoring of their house? 
 
I have an old TED (The Energy Detective) dating from around 2007, which sort of still works, but I only have four CT's with it and they are split 200A and not accurate for branch circuits.
 
I've looked at their newer system with a "Spider" that does 8 circuits (and I think you can have multiple), and it's pretty pricey ($470 for mains plus 8 CT's).  There's also some indications it is not working well with Home Assistant (at best it has light enough use little discussion).  I can't test as the old one doesn't use the same API.  But they do have a good reputation for accuracy and durability.
 
Emporia has a multi-circuit system, but it is cloud only (I asked about an open API, and they said that's not their business model). 
 
Sense, also cloud based, purports to monitor only the mains and figure out what devices you have; not sure I believe in that yet, especially given a lot of their statements are future looking (we will use your data among others to figure this out, basically). 
 
Open Energy Monitor looks overall like a good choice, but it's based in the UK and not sure how long or much trouble or cost to buy stuff from there. But it looks like the most DIY friendly complete system.
 
Brutech is interesting and looks like it may be about the price of TED but with more CT's, but also don't see a lot of use of it on it relative to Home Assistant, though it looks supported.  And probably easier to get out of Canada for the US than the UK. 
 
Anyone using variations of these or others, what do you recommend?   Specifically for local data storage and monitoring, not cloud based.
 
 

Linwood

Active Member
So, as I sit here cooling off (working in a garage in Florida is hot, even in "winter")... 
 
I did a lot of reading, inquired to various vendors, and bought something.  Here is some of what I found in case others are looking: 
 
TED: They have a new system, it can attached two 8-port Spiders to each of their measurement units (which otherwise just do the mains), so with a "pro" single system you can measure 16 circuits.   Their system uses an in-panel device to collect data, and uses powerline transmission to their network enabled device you place elsewhere. That's the same technique used in their very old system I have, and powerline transmission is great when it works, and very frustrating otherwise.  The vendor assured me I would have no trouble, but their old system worked in my bath, kitchen and a few other places, but not my office or network closet where I wanted it (and yes, I tried both legs). They warn some devices, including UPS's, can interfere -- and of course in my office and network closet I have UPS's.  Note I'm not trying to use powerline through the UPS, it's just on the same circuit.  To be fair the actual implementation is probably 10 years newer and hopefully better.
 
On the good side for TED they immediately said they had an open API, and provided it.  They have both a query API, and a push API to push data to a service.  I went over the query API in some detail, though, and could not find how to get per-circuit data (they assured me it was there, but without actually telling me where).  The push service does have it.
 
On the good side I had a TED device still working perfectly after 10-12 years.  The bad news is I just didn't get comfortable that the powerline issues wouldn't be a problem, and I didn't feel like rolling my own receiver for their data (it appears aimed at 3rd party web services, but no integrations were listed; they said they never heard of Home Assistant.  They do have a 30 day satisfaction guarantee.
 
I decided to pass, but I think they are likely a good solution especially if you do not need it integrated with some other system; very packaged, very long term good reputation.
 
OpenEnergyMonitor.org sells hardware.  It looks quite good, open source, integrates with a lot of stuff. I found it a bit difficult to figure out what I would actually need to make it all work hardware wise.  They are in the UK, so would need to deal with shipping.  I passed as I found a similar solution that looked easier to deal with, but I think this looks pretty promising.  They also are linked to EmonCMS's web service for doing analysis, so if you buy their hardware you can get free web site usage (you can also host EmonCMS locally).  I'm still unclear how I could have gotten 17 circuits monitored, but I suspect I can with multiple emonPi/base/something.  I passed, but it also seemed a good solution.
 
Brultech / GreenEye Monitor / GEM: I almost bought this one.  It's another commercial (vs open source) product, and someone has already done integration with Home Assistant. It supports a whopping 32 inputs in one place which is the most I have seen (be prepared for a wiring challenge to get all those wides inside and neat).  It's wifi or ethernet.  They have been around (but pretty low key) for a long time, and I found no significant complaints.  They keep up with integration and show many compatible systems (Charmed Quark, Home Assistant, HomeSeer, and many others).  They respond to inquiries quickly and accurately.  They are in Canada, so still have some delay for shipping, but better than the UK.  overall quite pleased.  I'd say they were my 2nd choice.
 
Emporia Vue: This is a really cheap device (I use that vs affordable based on a lot of comments online).  They are also entirely cloud based.  I asked if they had an API for local data storage and was told "we do not plan on allowing for local storage... [our] business is developed around collection and analytics of energy data in the cloud".  I read a bit between the lines that they may be  using your data, not just selling data storage.  They were very kind though and referred me to other local-storage devices.  My take is this is a good system for people who want to do a lot of circuits really cheaply and do not mind cloud storage.
 
Sense: So... I just have no idea.  It's a mains-only sensor, that sends data to the cloud, and tries to use load change characteristics to infer what your devices are, and how much each is using.  It purports to learn (both from you, locally, and from all others in aggregate) and improve over time.  I read all sorts of mixed reviews, some say it works, some that it doesn't; they basically say "be patient". Personally I'm not enamored with the idea of inference -- there's just too much variation, e.g. my new hot water heater is a heat pump, except when it switches ti resistance; or to both; the heat pump has different running levels.  And all that gets merged with everything else in the house. Is it possible to eek out which is which from the total?   Sure, maybe.  I have a lot more confidence if there's a probe on each relevant circuit.  Pass.
 
LeChacal.com:  So this is really interesting.  It's a Raspberry Pi (most any version) based system with stackable daughter cards.  A card might handle 7-8 different CT's.  It is less expensive than many alternatives, depending on how many CT's you want.  They say you can stack (didn't see how many, they show a picture with 5, so that's about 35-40 inputs.  You can then customize the case with little add-on sections to get the right height.   rPi's of course are very DIY friendly.  I thought a lot about this one, but it had two drawbacks -- they are in the UK as well, and there's a lot more pieces and parts and if I had to order extra stuff, it would drag on and on for a while.  The other is I didn't like the cube form factor you ended up with, it did not look that friendly to mounting in some kind of cabinet beside the panel.  I could probably work something out, but I liked a more flat form factor.  This was probably my 3rd choice.
 
IotaWatt: THis is what I ended up choosing.  It is also an open software project, but they sell hardware that is certified appropriately, and have put a lot of effort (it is apparent) into making sure their CT's, reference adapters, etc. all work and play together well.  There's an active community, and the project is in Git if you want to build your own.  It's ESP8266 based, so low power and wifi (no hardwired ethernet is one drawback).  Each device can monitor 14 inputs (plus a voltage reference) which was a bit short of what I wanted, then I decided that I might improve my wiring mess by using two, one on each side of the panel.  These are relatively inexpensive, so two iotaWatt's and all the CT's were about the same as the TED or Brultech.   It integrates in a push technique to PVOutput, Emoncms and Influxdb, the latter two (maybe all) are in turn integrated with Home Assistant.  They also have a documented REST interface if you want to pull data directly to Home Assistant.  The unit itself has a very nice graphing interface for direct looks at real time data without any of the integrations.  The ESP8266 may sound like it is wimpy, but I just looked and mine is sampling many times per second and still driving a web server.  It also does 3 phase, and can (but does not require) monitor a voltage reference on each US split leg if you want a bit more accuracy (I am doing that but wondering if the improvement in data accuracy is not below the level of absolute accuracy on the measurements; most US split legs are pretty balanced). 
 
I ordered it (about 2 days free via USPS) and got 19 or so monitors, two units for about $520.  If you only monitor 14 or less points, you save a lot over that. I then spent a bit for cabinets and conduit at home depot to get ready, and put it in yesterday.  It took me about 3 hours to get all the CT's on and going (it's going to take hours at some point to dress up the wiring!) and it came up and worked first try.  Very easy to get configured.  I spent a lot more time getting the conduit and boxes mounted.  Note that the small CT's are solid -- you have to disconnect the load from the breaker to put them on, so those uncomfortable working in a panel would need someone qualified (the mains and 100A CT's are split so those are much easier to attach).  These solid CT's are going to be more accurate for low amperage loads. 
 
So now doing some calibration, figuring out how I want to integrate (a problem with having choices is you have to pick one - analysis paralysis). 
 
 

upstatemike

Senior Member
I use a GEM with Homeseer. It was an easy way to monitor dedicated circuits like my ovens and dishwashers. I am more interested in triggering events from individual circuit draw than I am in measuring or logging usage so this may not be as good for you as it is for me.
 

Linwood

Active Member
If anyone is curious, here's what my install looked like.  This has 18 current probes, four voltage (each one has each main).
 
If anyone is curious here's what it looks like with the boxes open.  The two small boxes on right and left are actual Orbit sprinkler boxes, which have a nice divider for high voltage (behind in this view) and low (what you see) and room for an outlet (where the transformers are plugged in).  The bundle of wires on each side of the panel tied in red wire ties are the new wires for the current transformers on different circuits.
 
This lets me monitor most of the relevant stuff, and ignores lighting and outlets in most rooms, since with LED lights now, and nothing more than the occasional TV or Google Home in the outlets, those are very low draw (and I can get them in aggregate by difference in the mains and everything monitored).   
 
Now for the hard work to figure out what to do with all this data.
 
 
i-n8K6BBN.jpg
 

vc1234

Active Member
Linwood said:
If anyone is curious, here's what my install looked like.  This has 18 current probes, four voltage (each one has each main).
 
If anyone is curious here's what it looks like with the boxes open.  The two small boxes on right and left are actual Orbit sprinkler boxes, which have a nice divider for high voltage (behind in this view) and low (what you see) and room for an outlet (where the transformers are plugged in).  The bundle of wires on each side of the panel tied in red wire ties are the new wires for the current transformers on different circuits.
 
This lets me monitor most of the relevant stuff, and ignores lighting and outlets in most rooms, since with LED lights now, and nothing more than the occasional TV or Google Home in the outlets, those are very low draw (and I can get them in aggregate by difference in the mains and everything monitored).   
 
Now for the hard work to figure out what to do with all this data.
 
 
i-n8K6BBN.jpg
 
Looks similar to what I used to have in my previous house.  The messiest part was/is to wire all the current transformers and connect them through the conduit to the measuring module. I used Brultech, iotaWatt did not exist at the time.
 
When I moved, I disconnected everything and took with me primarily because I did not want to be responsible for the equipment in any way.  The equipment is still in the box.  I just do not have enough motivation/energy of going through wiring CTs again.  I'd rather use something similar to https://www.mitsubishielectric.com/fa/products/lvd/lvcb/pmerit/mdu/index.html if it were available with some reasonable open communication protocol.

 
 

Linwood

Active Member
While I'm visiting -- Home Assistant and IotaWatt work really well together going through InfluxDB and Grafana.  Here's an example of it all going together.  I said "Hey Google, show energy on master bedroom tv" and viola... 
 
i-V7dXNpt.jpg

 
Iota stores data in InfluxDB, where Grafana can get to it, some other data gets fed from Home Assistant like temperatures including thermostat set tem, heat pump hot water heater status, etc., then Home Assistant tells the LG TV to pull the dashboard and display it.
 
Absolutely no use, but very cool.   B)
 

apalrd

New Member
I have a Brultech GEM system with all 32 channels populated. I have 33 circuits in my panel, so I decided to use the Micro-40 donuts on every circuit except two large 240V circuits, which I used Split-60s on. I also skipped one circuit, a whirlpool tub pump that is rarely used. I did not have any channels left to monitor the mains, but I don't see a need when I am monitoring all of the circuits individually. My house has a fairly well thought-out breaker layout, so each bedroom has a dedicated 15A circuit, and in the rest of the house lighting and plugs are on separate circuits.
 
Installing all of the CTs in the panel was not a small task, and took around an hour with power shut off. I basically started from the top and worked down, labeled each CT in order, and zip-tied all of the CT wires together and ran them as far from the AC wires as I could. I ran all of the wires out the bottom of the panel, and then mounted the GEM next to the panel. After that, I spent a few more hours setting up the GEM outside of the panel, neatening up and labeling all of the wires, etc. I looked for pictures of this process (I installed it last summer) but couldn't find any on my phone. I am using it with a wired Ethernet connection, and it sends data to Node-Red + MQTT + InfluxDB + Grafana. The software on the GEM itself is quite basic and took awhile to figure out, but it has had no issues since I installed it. Node-red is setup as an HTTP service, which the GEM posts to at a 5s interval.
 
I picked the GEM because of the high channel count, and because it did not rely on a cloud service at all. There's no AI trying to guess what load is what, just real numbers that I can analyze myself. I like that I can monitor every single circuit separately, so tracking down phantom loads and problem appliances is easier. I'm also not a fan of using wifi for something permanently installed like this, where running a new cat5e cable is not an issue.
 
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