My new solar and Powerwall installation

[ecarfan]

Some people have asked who my solar installer is and what my system cost.

I am using a local company based on the San Francisco peninsula called Dura Foam Solar (they began as a foam roofing company, and I have a foam roof, that is in part why I chose them). As far as I know they do not work outside the Bay Area but you can always contact them directly and ask. See Solar Power – Dura Foam Roofing

I am not going to publicly post the exact cost but I will say that for the system as I described in my first post in this thread, with the Powerwall, and before the Federal tax credit, it is somewhere near $40K.

To those who may point out that I could have directly purchased all the individual system components for much less and installed them myself (or found someone to install them for a lower cost than what I am paying), my response is that I did not chose to do that for a variety of what I consider good reasons, and leave it at that. I bring that up because I know that in other TMC threads about solar installs some people have posted expressing incredulity at the cost of a solar system, saying that they could do it for much less. And good for them.

Please do not turn this thread into a debate about the pros and cons of self-install or similar. I very much want this thread to stay focused on my solar installation and the Powerwall since I have not yet seen a thread on TMC where a member has posted about their solar/Powerwall installations and many people are interested about the subject.

Thank you. More information about my install coming soon. Today a Tesla Energy employee is onsite and working with the electricians, and she is awesome! So smart and helpful.

 

[Garlan Garner]

Some people have asked who my solar installer is and what my system cost.

I am using a local company based on the San Francisco peninsula called Dura Foam Solar (they began as a foam roofing company, and I have a foam roof, that is in part why I chose them). As far as I know they do not work outside the Bay Area but you can always contact them directly and ask. See Solar Power – Dura Foam Roofing

I am not going to publicly post the exact cost but I will say that for the system as I described in my first post in this thread, with the Powerwall, and before the Federal tax credit, it is somewhere near $40K.

To those who may point out that I could have directly purchased all the individual system components for much less and installed them myself (or found someone to install them for a lower cost than what I am paying), my response is that I did not chose to do that for a variety of what I consider good reasons, and leave it at that. I bring that up because I know that in other TMC threads about solar installs some people have posted expressing incredulity at the cost of a solar system, saying that they could do it for much less. And good for them.

Please do not turn this thread into a debate about the pros and cons of self-install or similar. I very much want this thread to stay focused on my solar installation and the Powerwall since I have not yet seen a thread on TMC where a member has posted about their solar/Powerwall installations and many people are interested about the subject.

Thank you. More information about my install coming soon. Today a Tesla Energy employee is onsite and working with the electricians, and she is awesome! So smart and helpful.

My apologies ecarfan. I was just trying to help folks out and vouch for Solar Edge. Its your thread.

 

[wang5150]

Is the PowerWall able to be installed on the exterior of the house using a different enclosure?

I'm wanting to have 2 of them installed on the exterior wall of the house near the existing inverters.

 

[K-MTG]

Also curious on the cost, and who you used for the Solar installation. Thanks for sharing your progress!

I have Solar City for Solar but Baker Electric Solar reached out to me for the powerwall with a estimate of $11k.

Not sure if that is a good deal. If it is my only option I will have to pull the trigger or wait for powerwall 2.0

I installed mine with my son. Solar is a very lego type installation. There are no shingles to remove or anything.

My system cost approx. $8K in total. 54 panels. You can keep track of my progress by clicking the link below.

Does that include the powerwall? Very good price

 

[Garlan Garner]

I have Solar City for Solar but Baker Electric Solar reached out to me for the powerwall with a estimate of $11k.

Not sure if that is a good deal. If it is my only option I will have to pull the trigger or wait for powerwall 2.0



Does that include the powerwall? Very good price

No powerwall.

 

[schonelucht]

I am not going to publicly post the exact cost but I will say that for the system as I described in my first post in this thread, with the Powerwall, and before the Federal tax credit, it is somewhere near $40K.

I must admit I'd have expected a good deal less but sometimes being able to get a trusted installer who takes care of literally everything is priceless. Do you have an estimate on how much the system would have been without the Powerwall? And possibly also an idea of what kind of savings you are expecting from the system?

 

[ecarfan]

My new system is wired up and ready for final inspection by the county tomorrow. If it passes inspection, the new solar and the Powerwall will be started up next Monday. Tesla Energy will be at my house for the startup to make sure everything goes well.

 

[ecarfan]

s the PowerWall able to be installed on the exterior of the house using a different enclosure?

I cannot answer that question. I do know that the Powerwall can be mounted on the exterior of a house in its own standard enclosure. I did consider doing that but my solar installer figured out a layout such that all the components pictured just above would fit on that wall of my garage, which is the only available wall space I have in my small garage.

Do you have an estimate on how much the system would have been without the Powerwall? And possibly also an idea of what kind of savings you are expecting from the system?

I do not have an estimate for what my solar system would have cost without the Powerwall.

As far as the savings I expect, my electrical bill has average about $170/month for the past few years that I have had two Teslas. WIth my new solar/Powerwall system I estimate my monthly bill will be about $10/month, the standard California "Minimum Bill" charge.

 

[Cosmacelf]

Nice rigid conduit work! Looks very well done.

 

[Alketi]

Question about the SolarEdge/PowerWall combination:

In the event of a power outage, does the SolarEdge inverter automatically switch both the house and solar panels entirely over to the PowerWall?

 

[Cosmacelf]

Question about the SolarEdge/PowerWall combination:

In the event of a power outage, does the SolarEdge inverter automatically switch both the house and solar panels entirely over to the PowerWall?

It's more complicated than that. First, the entire house is not available to be backed up. You have an essential loads electrical panel that contains just the loads that you want backed up. So, following a power outage, the essential loads panel is disconnected from the main load panel and thus from the grid using an automatic transfer switch. Then about 5-10 seconds later, the Inverter powers the essential loads using the solar array power. Any excess power from the solar panels is fed into the Powerwall battery. Conversely if the solar array isn't generating enough power for the essential loads panel, then power is drained from the Powerwall.

 

[tomas]

It's more complicated than that. First, the entire house is not available to be backed up. You have an essential loads electrical panel that contains just the loads that you want backed up. So, following a power outage, the essential loads panel is disconnected from the main load panel and thus from the grid using an automatic transfer switch. Then about 5-10 seconds later, the Inverter powers the essential loads using the solar array power. Any excess power from the solar panels is fed into the Powerwall battery. Conversely if the solar array isn't generating enough power for the essential loads panel, then power is drained from the Powerwall.

So is part of any install then splitting out current panel into essential and non-essential? Any guidelines for that decision?

 

[nwdiver]

So is part of any install then splitting out current panel into essential and non-essential? Any guidelines for that decision?

It's possible to backup your entire house... just A LOT more expensive. I've got a 4kW off-grid inverter I use if there's an outage... it does fine to run the entire house but my home is small and I have inverter driven mini-splits for AC that don't require much power.

For hotter climates most people would probably consider AC to be a 'critical load'... if the system can run your AC then it can probably run the entire house... with the exception of large resistance loads like dryers and stoves.

 

[ArtInCT]

So is part of any install then splitting out current panel into essential and non-essential? Any guidelines for that decision?

Yes, there are... you have to identify what outlets and or hard wired items are on each breaker and then you can decide if that circuit is essential or non-essential. I walked thru this with my electrician who then took notes regarding the Watts he saw being consumed in operation and startup (like motors starting). It essentially took about 1.5 hours of he and I with a walkie talkie pair. In my particular environment, we left out the dual ovens and a few spare guest rooms to fall into a kW hour budget.

Essential items were sump pumps, furnace, refrigerator, stove top, kitchen, living room and bedroom, etc, etc... those areas that we use a lot. If you do not go into a room very often then perhaps it could be considered non-essential.

The essential circuits get moved from the primary load panel to the break out generator / PowerWall load panel.

Although this sounds simple it is crucial and somewhat tedious, especially if outlets are hidden behind heavy furniture, appliances, etc.

 

[Garlan Garner]

It's more complicated than that. First, the entire house is not available to be backed up. You have an essential loads electrical panel that contains just the loads that you want backed up. So, following a power outage, the essential loads panel is disconnected from the main load panel and thus from the grid using an automatic transfer switch. Then about 5-10 seconds later, the Inverter powers the essential loads using the solar array power. Any excess power from the solar panels is fed into the Powerwall battery. Conversely if the solar array isn't generating enough power for the essential loads panel, then power is drained from the Powerwall.

That's not true.

You don't need an essential panel. You can connect eadh Solar Edge Inverter to 1/2 of you primary panel and all of your 120v appliances will work. The only issue is that 240V appliances probably won't work because both 120v sides would have to be 180 degrees out of phase and that may not happen.

I have 2 of them with battery backup..... See my Inverter progress below.

 

[Cosmacelf]

Fine. The NORMAL install, and the way the SolarEdge/Powerwall documentation reads, you have an essential loads panel. But if you really know what you are doing, and either have an unusually small house or an unusually large solar panel array, and not not much AC load, you might be able to design a system such that your whole house is backed up. YMMV.

 

[ecarfan]

Fine. The NORMAL install, and the way the SolarEdge/Powerwall documentation reads, you have an essential loads panel. But if you really know what you are doing, and either have an unusually small house or an unusually large solar panel array, and not not much AC load, you might be able to design a system such that your whole house is backed up. YMMV.

Yes that is correct as I understand it. Your post last night (upthread) is mostly correct in describing my particular install, however it is my understanding that in my particular installation the switchover in the event of a grid failure is not automatic, it must be done manually by me. I will try to confirm that and post again.

 

[MP3Mike]

You don't need an essential panel. You can connect eadh Solar Edge Inverter to 1/2 of you primary panel and all of your 120v appliances will work. The only issue is that 240V appliances probably won't work because both 120v sides would have to be 180 degrees out of phase and that may not happen.

I don't think that would pass code as it could back feed power to the lines, and other houses around you, when the power goes out. You have to have some kind of transfer switch to cut off the feed from the utility before you can switch to generator/battery power.

 

[ecarfan]

you have to identify what outlets and or hard wired items are on each breaker and then you can decide if that circuit is essential or non-essential

Yes that is correct as I understand it. But you also have to take into account the output of your solar system and Powerwall (in my case) and not include so many circuits in the critical loads panel (or "essential loads panel" as @Cosmacelf calls it) that you could overload them during a power outage. During an outage you have to use common sense and an understanding of the current draw of whatever is connected and being used in the house and make sure you don't trip the breakers in the critical loads panel.

In my case, because I have just a single Powerwall and a just under 10kWh solar system, I chose to limit the circuits in the critical loads panel to my refrigerator, some outlets in the kitchen and my spouses home office, some overhead lights, and a bathroom. So during a power outage, assuming a reasonable level of solar power production, I should be able to run my refrigerator for a majority of the time day or night, use an 1300W induction hot plate in the kitchen to boil water and heat food, plug in a few low amperage items as needed, my wife can run her office equipment and we can charge our phones/tablets,etc.

Given adequate sunlight I will be able to maintain that level of electrical power indefinitely.

 

[Garlan Garner]

I don't think that would pass code as it could back feed power to the lines, and other houses around you, when the power goes out. You have to have some kind of transfer switch to cut off the feed from the utility before you can switch to generator/battery power.

I have a whole house disconnect switch setup. Its made by Outback. I got my system wayyyy before powerwall became available.

It kept me from having to have a separate critical use panel.