Smart Solar/Battery

heimlich

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I have a few of these switched power receptacles. On one side there is a plug for a device. When that device is on it turns on all the other plugs power. For instance, hook a computer in. When the computer is on it powers the other plugs which may be connected to monitors. So that when the computer goes off the monitor goes off.

In your example, the grid is the computer.
 

svetz

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Looks like all the panel makers have remote versions now and the breaker prices aren't too bad ~$60 for the SquareD to the right. So a lot less George Jetson then last year. Sadly, they don't all report energy data and they all seem to require a special panel.

There are quite a few LoRa smart switches too now; this adds to the large number of wifi switches. Ewelink has a $38 30 Amp switch, but it won't support 240V split phase.

This guy gets an "A", but I'm pretty sure it's a wifi switch flipping a contactor in a box you could make for 1/2 the price. Have to run, but will update this post later if I find the "perfect" device.
1614173154658.png
 

Supervstech

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Looks like all the panel makers have remote versions now and the breaker prices aren't too bad ~$60 for the SquareD to the right. So a lot less George Jetson then last year. Sadly, they don't all report energy data and they all seem to require a special panel.

There are quite a few LoRa smart switches too now; this adds to the large number of wifi switches. Ewelink has a $38 30 Amp switch, but it won't support 240V split phase.

This guy gets an "A", but I'm pretty sure it's a wifi switch flipping a contactor in a box you could make for 1/2 the price. Have to run, but will update this post later if I find the "perfect" device.
Ok... how did you format your response image like that?
 

svetz

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$39 Option? Must be something better than this.... something with power monitoring...

ItemImageSize (LxWxH)Price
30 Amp 2-pole Contactor w/120V coil
51I4K5khFFL._AC_SL1500_.jpg
87 x 72 x56 mm$10
WiFi smart Plug (or signaling of your choice)
61hEPDlj18L._AC_SL1000_.jpg
88*38*23mm$9
Box
(Love how this is the most expensive part)
51V+pjfDtbL._AC_SL1100_.jpg
150 x 110 x 70 mm$12
Fuse
619ET3RliCL._AC_SL1100_.jpg
58mm x 16mm x 45mm$8
Simplified Wiring Diagram
1614197156340.png
$0

Update: Should probably fuse the smart plug for Murphy's sake.

Ok... how did you format your response image like that?
?
You mean using Tables and cells?
 
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Q-Dog

¯\_(ツ)_/¯
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I like this idea. I replace outlets and switches, pull cable, replace breakers, even replace water heaters,
but there are still some things about 120/240 that are magic to me. If my 240V load (water heater for
example) has only L1, L2 and ground, where do I get the Neutral? ¯\_(ツ)_/¯

My water heater has a timer that we sometimes override when we do laundry or take a shower outside
of our normal times. This would be a circuit to make that timer a little more smarter. I'd like to tell
Siri to turn on/off the water heater.
 

svetz

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If my 240V load (water heater for example) has only L1, L2 and ground, where do I get the Neutral?
That would be a problem. Any nearby 120V circuits (preferably in the same junction box)? It doesn't have to be on the same circuit. 240V smart sockets exist, but I haven't seen anything inexpensive. Some of those relays can be energized with 24 Vac, so you could possibly use a 10:1 transformer and one of the cheap 24V wiFi relays.

Personally I'm still hoping something better comes along.
 

svetz

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Aeotec 40 Amps, Z-Wave, $95
36c43a22-a8a2-4dd0-ae13-0394eb106618._CR0,0,600,600_PT0_SX300__.jpg


Updates
  1. Thought this was familiar, jwu_cc recommended it in post #2 ;) Should handle the no neutral case.
  2. Hmmm... has power monitoring too
  3. Started a thread on the Emporia Vue for power monitoring as an alternative to an all-in-one switch/monitor solution. A number of members have them so possibly they can provide feedback.
 
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Q-Dog

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OK, so there is no special magic. 😲 Oh well. Our water heater is in a closet and there is an outlet a couple of feet away on another wall. I could probably drop an outlet into there without much trouble.
 

Skyguy

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I had a similar question and came across lumin- https://www.luminsmart.com/ it retrofits to an existing panel so no critical load panel needed, you use the same panel/breakers you already have. You can control 12 circuits (6@60a and 6@30a) on the entire panel. You can also get another set of CT’s and/or an additional unit if you want to control more circuits. It’s more of a load shedding tool to maximize your battery/solar life than a smart panel in a way.

I saw this panel that was a complete retrofit (my current project is new construction so I considered it) but has too many unknowns for me- https://www.span.io/ Cost was 3x that of the lumin and my old school electrician had a lot of good “what if” questions when looking at it. It’s more of a control everything approach.

I have a LOT of questions about my final system design/sizing, but the ability to load shed the largest energy hogs (schedule/priority) without the need for an inflexible critical loads panel makes a huge difference for installation/service/use. If it ends up making sense for my application i may dive in with it.

The other side of the coin is more control = more things to potentially go wrong. You can buy a larger solar system/battery bank for the cost of the smart control system reducing the need for one in the first place. Thanks for bringing us all down the rabbit hole...
 

svetz

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Sweet! Thanks for posting those, I didn't know about either device.

That's the beauty of procrastination, if you wait long enough more clever products start popping up. The "Span" is another smart load center like the Leviton in #6. The Lumin is cool, looks like it can control twelve lines, but only has two current transformers, and can go to 4? Wonder how well the lumin can make use of excess solar power (its a tricky problem, for example on my system the microinverters get throttled back so they're only producing what I'm consuming, but if you knew how much power was actually available you could, for example, turn on car charging if there was enough).

For me, the perfect product would be inexpensive circuit breakers I could retrofit in my Square D (that both allowed remote on/off as well as current measurements) as the load center is an interior hallway.

On the upside, 15 amp smart sockets with power monitoring built-in are fairly inexpensive now. Haven't seen much beyond 15 amps through.

...the ability to load shed ...
[In TV Ronco announcer's voice] Now you too can cause rolling blackouts within your home just like the Grid Operators!

...Thanks for bringing us all down the rabbit hole...
What are friends for?
 

Skyguy

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Svetz- I contacted Lumin to see if I can add a set of CT’s to the PV current and compare the PV output to the main panel load and if there is excess PV generation turn on a load dump such as a water heater or EV charger. I don’t have an electric car but will have a smaller battery to start off with so I can appreciate where you are coming from.

Being able to control a “battery” like the water heater storage tank will allow any excess generation not to go to waste. I’d be using Lumin backwards ie in off grid mode most of the time instead of how it is designed to be used.

I’m thinking to avoid “self rolling blackouts“ which be offset if the inverter goes into grid bypass mode since I do have grid power but not the desire to pay the utility the demand/fees for the privilege of NOT using the grid in a grid tie system.

whats on the other side of your hallway? Maybe you could mount the lumin box in a closet or something on the other side of the wall? It does seem like a smart breaker could be much simpler approach. Maybe procrastinate a little longer and rabbit hole pops out in China somewhere with the perfect solution....
 

svetz

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Cool beans! We're in the infancy of this stuff. Won't be too much longer before those guys start recognizing multiple batteries and some complex programming (e.g., I have a house battery and an EV battery to use, but the EV needs X amount of Wh to drive to work by 6:00 AM) and figures out how to manage your microgrid.

I’m thinking to avoid “self rolling blackouts“ which be offset if the inverter goes into grid bypass mode since I do have grid power but not the desire to pay the utility the demand/fees for the privilege of NOT using the grid in a grid tie system.
Whereas I want to create rolling blackouts inside my house, no critical circuits here and a good net-metering agreement ... everything has access to the micro-grid (combination of battery and solar).

E.g., during the day when I have solar and the house batteries are full I'll want to charge the EV. But if I don't have enough solar during the day I want the EV charger switched off. Or, if I'm really hurting for power, the system can figure out what to do (e.g., cut off everything and just turn the fridge on every couple of hours for 15 min (or via IoT a fridge temp sensor).

...whats on the other side of your hallway?
On the other side is the kitchen. I have the DIY solution in #24, so I'm not destitute. Also started this thread, if something comes of it I won't need additional current measuring devices.
 
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