General consensus on grid tied battery systems

[nomadh]

I'm seeing lots of talk about batteries on grid tied systems but they all seem "at the cusp". Unfortunately in San diego Net metering is running out and if I want in I need to jump soon. I'm currently being offered a string inverter system using ABB inverter or for just a few hundred more a solar edge system. They claim both systems will have the option of adding a battery after the fact. The tesla for the solar edge and a german battery for the abb,possibly Sonnenbatterie.
I'm ok with either I think although I am just now hearing about abb so I dont think they have been used much in the US. My main reason for wanting a battery is to have my solar and some after sun power during an extended grid down situation. The price is looking good either way running about $2.20 a watt skipping the 30% tax and going prepaid lease/ppa. The salesman doesnt know much about it and assumes the whole system will be shut down even with batteries when the grid is down. That seems crazy to me. Once you have the system to charge and balance the batteries you can add a disconnect and keep running off grid. Hell SMA can sort of do it now WITHOUT a battery.
Any info on how these new hybrid battery grid tied systems will operate and if emergency islanding will be a feature? I'm fine with a manual switch or aux socket. This would be for emergencies.


As an aside how complicated is it to Change out an ABB power one inverter for an SMA TL inverter. Similar technologies dual string inverters. Is it just a wire swap to get it running?
There is just no way I will pay thousands to have kilowatts of power on my roof and yet have no way to use any of it in an emergency.

[DanKegel]

How often are you expecting your power to go out?

It seems to go out for about an hour a month here, whenever it gets stormy, but that's not enough to make me want to plunk down an extra $7k or whatever for a battery yet.

[J.P.M.]

FWIW: Net metering 1.0 from SDG & E is indeed expiring, but NEM 2.0 will retain most of the benefits of NEM 1.0. Get yourself informed and don't rush/panic. Things are changing, but it isn't the end of net metering by any means as some/many had thought until very recently.

[solarix]

There certainly is a lot of anticipation for grid-tied storage. It promises to help the grid-tie as well as provide some off-grid capability. But, details are scarce so far and I bet this whole arena is going to be fraught with early-adopter problems. Don't hold your breath on storage options making grid-tie solar any more cost-effective either. Its likely to be a bad "value proposition" unless uninterruptible power is important to you. I'm sticking with recommending the SunnyBoy SPS system until the other storage options shake out a ways.

[nomadh]

How often are you expecting your power to go out?

It seems to go out for about an hour a month here, whenever it gets stormy, but that's not enough to make me want to plunk down an extra $7k or whatever for a battery yet.

I'm looking to cover myself for the bare minimum if it ever goes out for weeks or becomes fairly intermittent. I did just loose power for a few hours last sun during a rainstorm. If it kept raining and stayed out for a day I'd have the family room under 6 inches of water. Probably generator for the rainstorm but the sunnyboy is a great answer for the other.

[nomadh]

FWIW: Net metering 1.0 from SDG & E is indeed expiring, but NEM 2.0 will retain most of the benefits of NEM 1.0. Get yourself informed and don't rush/panic. Things are changing, but it isn't the end of net metering by any means as some/many had thought until very recently.

I've been looking for 3 years now. I missed the great great deals on prepaid leases back then. If I did it then I could have paid for my system practically and could have bought a sunnyboy and put it in a box as a standby now. It does look as though net metering 2 isn't to bad a deal but 1 is better and now that I have 8 people living in my house and my power bills are up to $350 a month in the winter its getting to be time to move. Funny thing is now that I decided that I like sunnyboy by a squeaker over solar edge. Naturally the vender giving me the financing wont do sunny boy. Funny thing is pricing is so good I can buy a sunny boy and install it in an emergency and still save money.
So part of this is best guess and I'm hoping someone here has a better educated guess than me.
Has anyone heard that IF you were to get one of these add on batteries to the solaredge or abb or enphase ect have any of them talked about the systems ability to run the panels and battery during a grid down situation? It seems every part needed will now be in place except the auto cutout switch to disconnect.

[GFS]

I'm seeing lots of talk about batteries on grid tied systems but they all seem "at the cusp". Unfortunately in San Diego Net metering is running out and if I want in I need to jump soon. I'm currently being offered a string inverter system using ABB inverter or for just a few hundred more a solar edge system. They claim both systems will have the option of adding a battery after the fact. The tesla for the solar edge and a german battery for the abb,possibly Sonnenbatterie.
I'm ok with either I think although I am just now hearing about abb so I dont think they have been used much in the US. My main reason for wanting a battery is to have my solar and some after sun power during an extended grid down situation. The price is looking good either way running about $2.20 a watt skipping the 30% tax and going prepaid lease/ppa. The salesman doesnt know much about it and assumes the whole system will be shut down even with batteries when the grid is down. That seems crazy to me. Once you have the system to charge and balance the batteries you can add a disconnect and keep running off grid.
Any info on how these new hybrid battery grid tied systems will operate and if emergency islanding will be a feature? I'm fine with a manual switch or aux socket. This would be for emergencies.

Hi Nomad,
I'm a fellow San Diegan in the same boat as you. Due to a wife medical condition, I need to have 24/7 electrical capability to my house. To that end, I am currently putting in a backup generator system and designing a solar grid tied solar installation that will have a battery backup capability. I can't speak to the ABB inverter system, but I can tell you what I've found out regarding the SolarEdge system.

Basically, SolarEdge took their SE7600 inverter and modified the input safety switch/box slightly to create their "StorEdge" inverter that has battery connection for electrical load backup and for load shifting. It has Tesla Powerwall input/output and a 5 kW Critical Load Distribution Box Output. Now this is where we come to something critical. For the solar inverter to act as a backup power generator with battery input, you have to have a separate critical load electrical distribution panel. I don't think SDG&E will approve any setup that allows you to power your main electrical panel with an inverter/battery setup. Too much possibility of that type of setup powering the main distribution lines in a blackout and hurting someone down the line. So having a separate critical load distribution panel is kind of standard for backup emergency power.

The nice thing about the standard SE7600 inverter is that this inverter can be upgraded to a "StorEdge" inverter with an upgrade (or so SolarEdge tells me). So I'm looking to get an SE7600 and upgrade later. Just make certain you have clearance below the inverter to install the upgrade box and go.

Just my 2c

Gordon

[ButchDeal]

Has anyone heard that IF you were to get one of these add on batteries to the solaredge or abb or enphase ect have any of them talked about the systems ability to run the panels and battery during a grid down situation? It seems every part needed will now be in place except the auto cutout switch to disconnect.

SolarEdge can definitly do that
take a look at the online documents:

http://www.solaredge.us/groups/us/solutions/storedge

[nomadh]

SolarEdge can definitly do that
take a look at the online documents:
http://www.solaredge.us/groups/us/solutions/storedge

I've seen this and it does mention backup power but so far I think this vague little bit is all I have found to go on. ITs kind of disheartening to think a main lynchpin of my 3+ years of shopping for solar and this is the biggest explanation I find. There are whole tv shows on preppers, there are national news tv shows on our creaky grid and it seems 1/3 America is dependent on a medical device yet it seems grid down solar power is still a "silly niche" market.

StorEdge™ Benefits: More Energy DC coupled solution allows high system efficiency PV power is stored directly in the battery No additional conversions from AC to DC Module-level power optimization for more power harvesting Simple Design & Installation A single inverter for grid-tied solar, backup power, and smart energy management Inverter includes all hardware required for automatic disconnection from the grid when needed Outdoor installation allows flexibility in battery location No special wires are required to install the battery. Installs with standard PV cables No high voltage or current during installation and maintenance Enhanced Safety Integrated Rapid Shutdown functionality Low current during operation Full Visibility Monitor the battery status, PV production, and self-consumption data Smarter energy consumption to reduce electricity bill Monitor remaining hours of backup power energy Easy access to the inverter during maintenance (outdoor installation) StorEdge™: Backup Power and On-Grid PV Solution White paper Single Phase StorEdge™ Solutions Datasheet

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[Amy@altE]

I strongly suggest you look into financing instead of leasing, it is usually a much better deal in the long run. But there are tons of other threads about that. GFS gave a nice description of how the grid tie battery backup systems work. You have to add an additional critical loads panel to connect your critical loads to. When the grid is up, both breaker boxes get power from the inverter. When the grid it down, the inverter shuts down its connection to the main breaker box, as required by UL1741, but continues powering to the critical loads from the power stored in the battery bank. If the sun is up, it will charge the batteries from the solar panels, if the sun is down, it will power your loads as long as the battery has power left in it.

Before you decide on going that route instead of a generator, use a loads list calculator online to determine your critical loads. Make sure the battery options you are looking at have enough power to handle what you are trying to backup.

[SunEagle]

I strongly suggest you look into financing instead of leasing, it is usually a much better deal in the long run. But there are tons of other threads about that. GFS gave a nice description of how the grid tie battery backup systems work. You have to add an additional critical loads panel to connect your critical loads to. When the grid is up, both breaker boxes get power from the inverter. When the grid it down, the inverter shuts down its connection to the main breaker box, as required by UL1741, but continues powering to the critical loads from the power stored in the battery bank. If the sun is up, it will charge the batteries from the solar panels, if the sun is down, it will power your loads as long as the battery has power left in it.

Before you decide on going that route instead of a generator, use a loads list calculator online to determine your critical loads. Make sure the battery options you are looking at have enough power to handle what you are trying to backup.

Actually anyone that requires a non interruption of power will need something to provide power until the generator can take over. That "cross over" would be a battery system like a UPS or Flywheel generated power. Both of those are expensive because they only work for short periods. But if you need power 100% of the time to run a critical medical device the costs become secondary.

[jflorey2]

As an aside how complicated is it to Change out an ABB power one inverter for an SMA TL inverter. Similar technologies dual string inverters. Is it just a wire swap to get it running?

Not quite. But in general you can do it without a lot of pain; SMA inverters are fairly flexible when it comes to string voltage, so it's likely your array would not need to change.

[ButchDeal]

I've seen this and it does mention backup power but so far I think this vague little bit is all I have found to go on. ITs kind of disheartening to think a main lynchpin of my 3+ years of shopping for solar and this is the biggest explanation I find. There are whole tv shows on preppers, there are national news tv shows on our creaky grid and it seems 1/3 America is dependent on a medical device yet it seems grid down solar power is still a "silly niche" market.

Bimodal systems are very well understood. You just are looking ate a new product made to work with an as yet unavailable batter. Outback power and xantrex make very reliable battery backup grid tie systems and have for many years. These along with solarEdge StorEdge will have two ( or more with some Outback versions) AC connections. The grid attached one will be disconnect during grid outage as required. On all three of their web sites you can download the manuals and installation documents.
The SMA TL is a different animal, more of a toy with an isolated manual 15a outlet.

[nomadh]

Actually anyone that requires a non interruption of power will need something to provide power until the generator can take over. That "cross over" would be a battery system like a UPS or Flywheel generated power. Both of those are expensive because they only work for short periods. But if you need power 100% of the time to run a critical medical device the costs become secondary.

Not that critical. I can go a day usually. I can certainly flip a switch or run an extension if needed. Like I said I want to be able to get to some of my power in a big emergency like grid down . no hospitals, no water type of regional or national emergency. And the most important feature is it needs to be cheap. I like the sunnyboy because its included free. Even with its obvious limitations.

[nomadh]

I strongly suggest you look into financing instead of leasing, it is usually a much better deal in the long run. But there are tons of other threads about that. GFS gave a nice description of how the grid tie battery backup systems work. You have to add an additional critical loads panel to connect your critical loads to. When the grid is up, both breaker boxes get power from the inverter. When the grid it down, the inverter shuts down its connection to the main breaker box, as required by UL1741, but continues powering to the critical loads from the power stored in the battery bank. If the sun is up, it will charge the batteries from the solar panels, if the sun is down, it will power your loads as long as the battery has power left in it.

Before you decide on going that route instead of a generator, use a loads list calculator online to determine your critical loads. Make sure the battery options you are looking at have enough power to handle what you are trying to backup.

Its a prepaid lease so we will still be needing finacing. We just wont be getting the 30% back with is fine because we are seeing prices around $2.20 a watt cash prepaid. We still get the 20 year warranty and maintenance and roof repair. The downside is they still own it when I need to hack it in an emergency. But whatever, its an emergency.


The description of how it works sounds exactly like what I want. The next problem is will it be $3k or $12k installed and running.