I have had a sense monitor installed in my office/shop for a few weeks now and thought that I would give people some idea of what I like, don’t care about and wish I could do… that I haven’t found yet.
The Sense Energy monitor device is a simple power meter that clamps on your incoming main lines and provide a pretty high frequency update of your usage (including spikes). It has features for identifying devices that uses some DL/ML code … which I didn’t really care about, but it is kind of neat.
I purchased the device to get a good idea of what power I was “really” using before I design a solar system to support it. If you are planning on doing a solar system, I highly recommend this $300 device (from Amazon) as it really takes out the guess work of how much power you need to engineer for.
My setup is a 1200sqft office area/kitchenette with forced air AC/heat, a 1200sqft shop with lots of high AMP wood working equipment cooled by a mini-split system and a 1200sqft garage (no AC). The office and shop are in Florida with Icynene insulation (so it is pretty sealed up). While I expect that the shop will pull a significant draw when operating (e.g., 3HP table saw), I am not designing the system to support the shop load (only the office area and maybe the mini-split).
Installing the Sense Monitor was really easy… there are a lot of videos online for doing that and generally they are easy to follow. Basically, you put the current clamps on the main 240v lines and stick the WiFi antenna out of the box so you can get to the network… done.
To give you a sense of the monitoring data I am interested in, you see the graph below showing the load from this afternoon. There is continuous load and then spikes where the AC kicks on. The surge for the AC is about double the continuous load for the AC. So, 4KW spike and 2KW draw. Pretty easy, it would seem that two 6KW Growatt (to provide split phase) would work perfect. However, …
If you look at the spikes over a couple of days, you have the normal usage and then every now and then you have a massive spike. I don’t know if that is real and/or what is causing it. My electric company is willing to put an expensive power meter on for me so we can tract it down and see if it is an equipment fault or something to be worried about.
Looking at just the massive spike, it occurs at random places (here it is during the AC running). You can see that it is a 10KW spike and sometimes as high as 15KW for a very short duration. So much for using two 6KW Growatt systems.
Sense Energy will also give you your usage over time so you can see the steady state usage. You can also pull this from the Power Utility (sometimes), but I wanted to know what I was really using and not an estimate farther up the line. Without the spikes, the steady state usage over a day is a reasonable 3KW/day (with some margin) which is what I would design the solar panels and batteries to.
Bottom line: Really inexpensive way to determine what you are actually using and not worse case usage. The data logging is nice and the tools to manipulate are intuitive. I do wish there was a way to down load the data locally so that I could do more analysis on it, but I have not found anyway to do that yet. In fairness, I haven’t asked yet either, but the all-knowing Google didn’t see thing. Once I have the office/shop engineered and installed, I will either move the monitor to the house (or buy another one) and start working on that design.
As always, these are my personal feelings and your mileage may vary. If you have any idea where the massive spikes are coming from, I would love to hear your view!
The Sense Energy monitor device is a simple power meter that clamps on your incoming main lines and provide a pretty high frequency update of your usage (including spikes). It has features for identifying devices that uses some DL/ML code … which I didn’t really care about, but it is kind of neat.
I purchased the device to get a good idea of what power I was “really” using before I design a solar system to support it. If you are planning on doing a solar system, I highly recommend this $300 device (from Amazon) as it really takes out the guess work of how much power you need to engineer for.
My setup is a 1200sqft office area/kitchenette with forced air AC/heat, a 1200sqft shop with lots of high AMP wood working equipment cooled by a mini-split system and a 1200sqft garage (no AC). The office and shop are in Florida with Icynene insulation (so it is pretty sealed up). While I expect that the shop will pull a significant draw when operating (e.g., 3HP table saw), I am not designing the system to support the shop load (only the office area and maybe the mini-split).
Installing the Sense Monitor was really easy… there are a lot of videos online for doing that and generally they are easy to follow. Basically, you put the current clamps on the main 240v lines and stick the WiFi antenna out of the box so you can get to the network… done.
To give you a sense of the monitoring data I am interested in, you see the graph below showing the load from this afternoon. There is continuous load and then spikes where the AC kicks on. The surge for the AC is about double the continuous load for the AC. So, 4KW spike and 2KW draw. Pretty easy, it would seem that two 6KW Growatt (to provide split phase) would work perfect. However, …
If you look at the spikes over a couple of days, you have the normal usage and then every now and then you have a massive spike. I don’t know if that is real and/or what is causing it. My electric company is willing to put an expensive power meter on for me so we can tract it down and see if it is an equipment fault or something to be worried about.
Looking at just the massive spike, it occurs at random places (here it is during the AC running). You can see that it is a 10KW spike and sometimes as high as 15KW for a very short duration. So much for using two 6KW Growatt systems.
Sense Energy will also give you your usage over time so you can see the steady state usage. You can also pull this from the Power Utility (sometimes), but I wanted to know what I was really using and not an estimate farther up the line. Without the spikes, the steady state usage over a day is a reasonable 3KW/day (with some margin) which is what I would design the solar panels and batteries to.
Bottom line: Really inexpensive way to determine what you are actually using and not worse case usage. The data logging is nice and the tools to manipulate are intuitive. I do wish there was a way to down load the data locally so that I could do more analysis on it, but I have not found anyway to do that yet. In fairness, I haven’t asked yet either, but the all-knowing Google didn’t see thing. Once I have the office/shop engineered and installed, I will either move the monitor to the house (or buy another one) and start working on that design.
As always, these are my personal feelings and your mileage may vary. If you have any idea where the massive spikes are coming from, I would love to hear your view!
