the SMART Home: Electrical Panels, and More

[SageBrush]

This thread is meant to share information related to the emerging field of smart appliances and their coordination. 'SMART' can mean different things to different people, and consumers have different devices and different priorities. E.g., one person may be focused on keeping their home energy flowing during a grid outage. Another person may be focused on storage arbitrage. My interest is in maximizing home PV generation for highest efficiency and least output to the grid. The common ground (hah!) is appliances have to modify their own supply dependent in part on what every other appliance is doing, the state of home generation now and for the next day, and environmental conditions of the home and outside.

Leviton
Sales 'smart breakers.' Each breaker is a wi-fi device that can turn the breaker on/off via phone app control. The app

• Has scheduling options at the breaker level
• Cannot island the PV generation from the grid
• Cannot be used to set up an off-grid profile

Span
Is IIRC a spin-off from Tesla. An entirely new panel replaces the one in place to offer both breaker level control and grid control. Control is via user preference using an app and allows

• On/off and scheduling at the breaker level
• Islanding of home generation to continue when the grid is down
• The user to designate an off-grid profile that takes both PV and battery into account

Legrand (NetAtmo)
As of 2/2021, only available in Italy and France. In addition to wi-fi controllable breakers, this vendor has an open API and supports the other leading home comm protocols from Apple, Google, and Amazon and IFTTT. It is on the dev track I hope to see advance.

 

[Akikiki]

Very cool thread. My definition is making appliances, lights, A/C, sensors smart to let me know what's going on and do stuff for me. I have an Alexa device in every room, some more than one. I can whisper and she hears. I've put smart switches, ceiling fans, all lights, cameras, water sensors, and other stuff almost every where. 47 panels and 2 Powerwalls. 75% of my panels are under NEM.

I like the SPAN box. My house is old and really not practical to replace existing with SPAN, but thinking about it anyway.

 

[SageBrush]

I thought a little more about what I want a 'SMART' home to do, and in a nutshell it comes down to the devices coordinating between themselves. When to turn on and when to shut off; and when to defer to other appliances.

It is a dance between the PV, the house heat pumps, and the EV.

In terms of comms, the smart breaker has to relay Amps. Mostly for the PV, but other devices could provide state info via Amp draw
The EV can relay SoC
The DHW has to relay water temp, and provide a COP chart
The house should relay interior temp and humidity, and its heat pump should provide a COP chart
And the brains of the home should be aware of outside weather

 

[h2ofun]

Very cool thread. My definition is making appliances, lights, A/C, sensors smart to let me know what's going on and do stuff for me. I have an Alexa device in every room, some more than one. I can whisper and she hears. I've put smart switches, ceiling fans, all lights, cameras, water sensors, and other stuff almost every where. 47 panels and 2 Powerwalls. 75% of my panels are under NEM.

I like the SPAN box. My house is old and really not practical to replace existing with SPAN, but thinking about it anyway.

What does 75% of you panels are under NEM?

 

[Akikiki]

Of my 47 panels 35 were installed in several phases. NEM is Net Energy Metering. It means, that when I produce power, i.e., daylight, part is used right then to power the house, and the remaining power is sent back along the grid. Its used by others connected and managed by the utility. I get credit for it. In effect, I am selling that extra/excess power that I am not using back to the utility. In my state, I get retail rate selling back to them. Right now, that about 32 cents a kwh. And I am lucky. years ago, I signed up for the EV rate pilot program. When I use power after 9 pm until 7 am, I buy it back for 26 cents a kwh. The utility is essentially a big battery for NEM participants. I've had solar since 2008. In those days panels were 200 watt. I've added more in later years and in 2019 before the 30% tax credit reduced, I removed 80% of my existing and replaced with 370's and moved to Solaredge because Enphase is terrible. from my experience.

In 2016, my utility decided the grid's sectors was saturated and allowed no new NEM connections. They created an alternative plan called Self-Supply. Where we add panels and energy storage. We charge our batteries during the day, and use them at night. If we need more, we are still connected to the grid and draw/buy more power from the grid.

But the grid goes down for any number of reasons too often here. And if we get a big blow or hurricane, we could lose the grid for weeks. So, one goal of mine has been batteries. When I produce more power than I use, annually my utility gives me a credit. I can use the credit to pay the monthly min service charge for grid connection which is $27.50, or take a check. This year's check is $492.

Adding batteries is possible, to back up my 35, but I get no tax credits for just batteries. And I did not want to risk adjusting my NEM. So, I opted to add 12 more panels with my two Powerwalls. The fed give us 26% tax credit and the state gives us 35% tax credit. Sounds good, but state tax credit does not include batteries. Over all after calculating the eligible tax credits against allowed system purchase, it equals out that the panels are free/paid for by tax credits, and my out of pocket was only for the Powerwalls.

The 12 panels are actually an independent/parallel system but luckily for me, connected to each other at the Tesla Energy Gateway. the 35 can help power the Powerwalls, but the 12 can not send back to the grid - prohibited - violates the max I can send back under NEM. My 12 charge the Powerwalls, and currently, I discharge them down to 20% daily using them after dark. This over all decreases what I am using that I had banked at the grid/utility. So, my annual check should be better with the Poweralls.

 

[darhall993]

Of my 47 panels 35 were installed in several phases. NEM is Net Energy Metering. It means, that when I produce power, i.e., daylight, part is used right then to power the house, and the remaining power is sent back along the grid. Its used by others connected and managed by the utility. I get credit for it. In effect, I am selling that extra/excess power that I am not using back to the utility. In my state, I get retail rate selling back to them. Right now, that about 32 cents a kwh. And I am lucky. years ago, I signed up for the EV rate pilot program. When I use power after 9 pm until 7 am, I buy it back for 26 cents a kwh. The utility is essentially a big battery for NEM participants. I've had solar since 2008. In those days panels were 200 watt. I've added more in later years and in 2019 before the 30% tax credit reduced, I removed 80% of my existing and replaced with 370's and moved to Solaredge because Enphase is terrible. from my experience.

In 2016, my utility decided the grid's sectors was saturated and allowed no new NEM connections. They created an alternative plan called Self-Supply. Where we add panels and energy storage. We charge our batteries during the day, and use them at night. If we need more, we are still connected to the grid and draw/buy more power from the grid.

But the grid goes down for any number of reasons too often here. And if we get a big blow or hurricane, we could lose the grid for weeks. So, one goal of mine has been batteries. When I produce more power than I use, annually my utility gives me a credit. I can use the credit to pay the monthly min service charge for grid connection which is $27.50, or take a check. This year's check is $492.

Adding batteries is possible, to back up my 35, but I get no tax credits for just batteries. And I did not want to risk adjusting my NEM. So, I opted to add 12 more panels with my two Powerwalls. The fed give us 26% tax credit and the state gives us 35% tax credit. Sounds good, but state tax credit does not include batteries. Over all after calculating the eligible tax credits against allowed system purchase, it equals out that the panels are free/paid for by tax credits, and my out of pocket was only for the Powerwalls.

The 12 panels are actually an independent/parallel system but luckily for me, connected to each other at the Tesla Energy Gateway. the 35 can help power the Powerwalls, but the 12 can not send back to the grid - prohibited - violates the max I can send back under NEM. My 12 charge the Powerwalls, and currently, I discharge them down to 20% daily using them after dark. This over all decreases what I am using that I had banked at the grid/utility. So, my annual check should be better with the Poweralls.

Anyone have the Span panel installed? I watched Ben Sullins video review, it looks interesting. I’m looking to step up from Sense, I have 2x200 amp panels and wonder if their system can present them as one system via their app interface.

 

[chadconway]

@darhall993 currently SPAN can have them both in one app, but represents them separately, but we are working to offer a collective view in the future which will be available via an over the air software update.

 

[woof]

@darhall993 currently SPAN can have them both in one app, but represents them separately, but we are working to offer a collective view in the future which will be available via an over the air software update.

Good to know! I've got two SPAN's on order for a new construction project. Just waiting for a hole to be dug, and then concrete, and framing, and ... it's gonna be a while!