Home Energy Monitors
Looking for advice from someone who has knowledge and/or experience with home energy monitors. I’m switching my home to all electric and want to monitor energy usage for all appliances.
In my case I have a 320 amp service with 2, 200 amp panels. I already have ductless heat pumps, HPWH, electric hot water boiler, water softener, well pump, booster pump and mechanical ventilation, all kitchen appliances that I am currently using, and will have an in-law suite that will have all electric appliances in the future.
It seems that the “Sense” home energy monitor is popular. Though I am curious about its accuracy and learning ability given all the appliances and mechanicals i’ll be using and seeing that it only connects to the main lines coming from the meter rather than individual circuits.
The “Gen2 Emporia” is another but has 16 individual sensors for circuits(I only would need to monitor major appliances so 16 would be enough for me). My only concern about this is the individual sensors are rated up to 50 amps and I have a dbl pole 60 amp breaker for my boiler.(maybe I could use 2 sensors, one for each line?)
Feedback about accuracy, price point, etc. is much appreciated. Thanks in advance.
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I have a Sense monitor that was given to me by Green Mountain Power. It does an excellent job of monitoring total electrical use and production from my solar panel. It successfully identified a bunch of my minor devices -- microwave, garage door opener, toaster, etc. It has not been able to identify the heat pump, the water pump, the refrigerator. For appliances that plug into 115v outlets you can get an inexpensive sensor that informs the Sense how much power is being used. However there is no inexpensive solution to monitoring the heat pumps. Though I am curious about how much power they use I am not ready to spend hundreds of dollars to find out.
https://www.greenbuildingadvisor.com/question/energy-monitoring-systems-which-is-best-combo-of-affordability-ease-of-operation-and-accuracy
Putting a sensor on each leg of the breaker accomplishes nothing. They can each carry 60A, not a total of 60A between them. That being said, just because the breaker is 60A doesn't mean it will ever see 69A. Look at the rating on the load, it may be 50A or less.
If the boiler runs on a true 240v circuit (double pole as noted by original post) without a neutral connection a single sensor will suffice, as the current flow through both legs of the circuit will be equal. If there IS a neutral connection then two sensors would be needed.
Thanks Tyler for the link to the analysis of alternative monitoring systems. The advice there was that the then new Emporia Gen2 system was much more reasonably priced than the alternatives. Has anyone been using that system?
I think it comes down to Emporia vs. IotaWatt. IotaWatt is highly configurable--you can get CTs with different current capacities from them, or get your own and program it to use them. So you can certainly get set up for the 60 A branch you want to monitor. It might be possible to do the same with the Emporia, but getting it set up to use a different CT and read out properly might not be possible.
I've had several over the years (TED, BLE, and a couple of others I can't recall), we are currently using Sense.
Sense is simple to install, it's accurate on total voltage, etc. The interface is nice, there is a lot of data you can download from your account to track your usage and it interfaces with 3rd parties so you can combine some of that data together and correlate outcomes.
But it absolutely SUCKS at identifying devices, so do not consider it for device level monitoring.
As an example, my current sense device list includes 5 refrigerators, 7 Air conditioners, and 5 central heaters. I've told sense exactly what I have but it still finds things and automatically adds them to the device report.
If they would just decide to support CT level monitoring, they would have an absolute winner on their hands.
You can add some plug in monitors from Kasa to track 15a point loads, but that's about it.
I find it useful, and the data compelling, but the lack of circuit level monitoring is a real miss.
I concur with Jayson on Sense. I have one and applaud the user friendliness and accuracy, but the ability to "detect" devices is dubious. Because of this fact I purchased their add on CT's (limited to two) and monitor my heat pump circuit. This takes the guesswork out.
This option might be of interest to you: DIY Energy-Usage Monitor. The plans are available for free via github (the link is included in the article).
Like others, I have Sense installed. I also have Accurite sensors installed to monitor relative humidity and temperatures in my ceiling and walls. Accurite is good at measuring the overall thermal performance. Good value, and published interfaces.
Sense is not very good at detecting ECM pump or fans. My background is chemical engineering, so I am looking at performance per device. Next house, I am looking for a smart panel (iospan) to measure cost per circuit. Sense does too much guessing through pattern analysis. But they have good analytics at a Macro scale. No predictive analytics..yet.
As a general caveat, why just measure? What the US needs is residential energy management systems that can take action. If the ceiling assemble is building up humidity, the turn on the zone valve to dry it out.
I would break my analysis into to what I want to control versus what I want to monitor. For example, if your refrigerator is running, do you want to catch it?
If you still doubt whether it is worth installing such a panel, discard all doubts and believe it is incredibly convenient and profitable. As someone who used to spend a huge amount of money for the consumed light, I can tell you that with these panels, you will see checks for an amount much less than you are used to. I installed panels from the https://www.luminsmart.com/platform/smart-electrical-panel company in my house, and for about a year now, I have been more than happy with this decision. Now I can control the number of watts that a particular energy source consumes in my house, and I can adjust the maximum. It is very convenient and profitable, so I advise installing it as soon as possible.