I added a second Sense monitor to my installation to get a better handle on the Tesla Powerwall providing power to my home during utility peak hours and to ensure I eliminate the demand charge. The upper half of the image is my new Sense unit monitoring the combined Solar&Powerwall output and the lower is just monitoring my solar only output. You can see in the upper image the “missing” morning solar - that missing power is recharging the powerwall from the prior evenings peak period. You can also see the stored solar being used to power my home until 8pm. I wanted to be able to separately track true solar produced and to track the powerwall.
Energy storage adds a whole new dimension to power/energy accounting ! From what I have seen, the Tesla app also shows energy flow between home, solar energy inverter, battery and grid, but presumably not as much detail as Sense.
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@kevin1 - Very true! Exactly why I added the second unit. Tesla’s app is pathetic, no detail, no export - basically just eye candy for a quick overview. I need the nitty-gritty!
This is all data gold that is usable sooner rather than later. Lovely.
I don’t know how they do their calculus but this is proof that Tesla (and other providers for that matter) should invest in Sense right away. Or at least: “And get a free Sense with your new EV/solar/battery”
Firm believer in throwing multiple Senses at problems rather than fiddling around and ultimately coming up with less usable data.
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The web interface to the Powerwall gateway can produce details on every aspect of the PV/PW operation albeit at much coarser inervals than the Sense.
I sample selected data each midnight and produce a series of day-by-day plots patterned after those from the Tesla app.
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When I was talking to the electrical supply house employee’s they knew I had solar but said the unit with out the additional clamps would work. Sense works great when the sun is down, but as soon as my solar panels start producing power nothing shows as being on all power is shown in negative ie: -1200 etc. I will be purchasing the second set of clamps hopefully that will cure my problem
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I am also going to be in the same boat soon. I plan to be setup like the first and treat solar or battery as solar.
The problem arises if the batteries charge from grid it’s going to incorrectly attribute that to Solar when they discharge. We almost feel a sense unit that has solar mean current and battery CTs. It would also be nice to be able to get a sense unit with a few dedicated branch monitoring CTs for things like EV, furnace, Dryer, oven/range that are dedicated circuits and would only have one device. The problem I with that is then filtering it out of the main CTs I assume.
The way sense is conceived, it’s supposed to infer from the current profile of your energy consumption what consumer just turned on or off. Therefore, it would be redundant to have separate clamps for dryer, EV, etc.
Ideally, Sense would make new hardware that has not only the existing utility and solar inputs, but also one for the backup battery. Since that is unrealistic in the short term, we could also use a “sensor” that comes with 4 clamps instead of 2. They can then be placed on the utility and backup battery wires. (I’ve tried to include a schematic for extra clarity, but this forum doesn’t allow the posting of “media”.) That would treat the utility current and the battery current as the same. For the purposes of tracking the consumers in your house – which is the original intent of Sense – that is a valid solution as both provide energy to your consumers. The dance where energy may be used to charge your battery from the utility or where your battery may be sending power to the utility are really irrelevant to the original purpose of your Sense monitor.
While I referred to the 4-clamp sensor as a concept, it would in fact be better to instead provide a splitter cable (similar to the extension cords they provide) with 3 plugs where 2 existing 2-clamp sensors can be connected in series to effectively act like a 4-clamp sensor. This has 2 benefits:
- It is probably simpler to make make that a true 4-clamp sensor and
- More importantly, it allows for the use of existing extension cords in case the clams need to split across 2 different panels.
The second point may not be obvious to those who never installed such a system before. But when you try to thread 4 clamps into different panels, you will realize that you can’t push the clamps though the conduits. The only way to do this is by threading the other end (with the plug) through the conduits. That means all clamps on the other end of the cable will end up in the same panel!
I’m looking for that splitter cable so that I can make my Sense work properly again! If anyone from Sense (the company) likes to contact me for more details of this idea, I’ll be happy to provide the information.
PS: I don’t have a Powerwall, but a Franklin battery. However, the same solution applies.
Thanks,
Chris
I get how it’s supposed to work but in practice it just has too much noise. Applying that tech to each circuit would give less things to listen to on each circuit in theory. Doing what it does in many circuits would require much more horsepower than the current unit has though. Being able to give this in a one device circuit and this is what is on it would further clean things up. I still love my sense but at this point it’s whole house monitor more than anything. For individual devices I am using the Kasa integration. That is 90% of what I have being tracked.
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I agree with you about it being quite terrible about inferring correctly what the consumers are that turn on and off. I have heard that the Sense company is updating the software and it supposedly has gotten better over time, but since the battery was installed, I haven’t really been able to use it and try it out.
Like you said, it’s fairly good at being a whole house monitor since it gives me 1W resolution while the battery app only gives me 100W resolution. That’s by far not good enough.
I still hope to get that splitter cable so that I can start using Sense again. I am quite shocked that there is no official solution out there from Sense since backup batteries have been picking up in popularity.