Battery Backup for a Grid-Tied system

[ButchDeal]

Well I guess that is why you are so confused. Dealing with mtv solar in WV.

[NetComrade]

ok, upon reading a few more threads on the radian, i think i will stick with the "ROI" advice and just get a generator and wait for something that plugs into solaredge... especially since I am already wired for one, and have one (just need to fix it)

maybe I'll get solar heated water instead this year.. was looking for a quick an easy write off

thank you all and I appreciate the educated and "common sense" responses.

[NetComrade]

Link below for the diagram by folks that installed my system including 2 solaredge and one outback. In followups they recommended to replace one of the solaredge with a scneider w6848 for the following reason

This past year we installed 20 or so fairly complex systems and, one thing we have learned is that battery back up systems work better if some of the PV is DC connected.

http://www.mtvsolar.com/Resources/Di...ckACCouple.pdf

[NetComrade]

I feel embarassed. The outbacks were part of the original proposal 3 years ago, I didn't get them because I didn't have that much $$$ at the time. This also has the explanation you were looking for

[QUOTEThe Inverters that best match the panel configuration and also allow for one of the inverters to be connected to the Outback inverter charger are a 5000 and 3000. The 5000w will have 21 panels connected (steep roof) and the 3000w will have the 14 panels on the flat roof. The reason for choosing these inverters is to properly DC load the inverters to as close to max DC input as possible (refer to the same web page you sent a link to). The 3000 allows for 4050W/ DC, we will be inputting 3920W. The 5000 allows for 6750W and we will be inputting 5880W. [/QUOTE]

Found AC Coupling Outback/SolarEdge doc.. I think it's what I am looking for. Thank you for your kind pointers.

http://www.outbackpower.com/downloads/documents/technotes/ac_coupling_tech_note.pdf

[ButchDeal]

I was going to say because two different arrays are at a different pitch on my roof, but I am not sure it matters too much with optimizers.

It doesn't matter at all with solaredge optimizers

[NetComrade]

Why do you have so many small inverters on a single site?

I was going to say because two different arrays are at a different pitch on my roof, but I am not sure it matters too much with optimizers.

[jflorey2]

"AC coupled" rings a bell... Will the mentioned Outback "fool" the SolarEdge they're connected to the grid?

It can. But you don't want to - believe me. The hoops you'd have to jump through are many. You'd need another breaker panel, a few relays, a few inverters like the Radian, a large battery bank etc. (Around $12K total.) There's a reason almost no one does this.

[ButchDeal]

I do have 2, Solaredge 3800 and SolarEdge 6000.

Why do you have so many small inverters on a single site?

"AC coupled" rings a bell... Will the mentioned Outback "fool" the SolarEdge they're connected to the grid?

I will also research what "bi-modal" means

A bimodal inverter has batteries and can work on the grid and off the grid.
It will not "fool" the solarEdge inverters but will control them to keep the battery charged and provide power to an emergency panel.
take a look at the OutBack Radian inverters:

http://outbackpower.com/outback-products/make-the-power/radian-series-inverter-chargers/item/radian-series-gs8048a-gs4048a?category_id=529

[SunEagle]

ok, thanks.. sounds the only other route (especially if I want to maintain remote monitoring of solaredge) is to install a 3rd hybrid inverter and tap into the 400V+ DC lines coming off the roof.

The other route it to swap a solaredge with a one that supports the Tesla battery, but seems like that never really shipped.

And probably won't for a while since they just voted on the merger. The focus will be somewhere else then a home battery system for a while.

On the flip side I just read an article about a company introduce something call the Totem. Looks cool and is much bigger then the PowerWall 2. No price yet

[Sunking]

You do not want batteries, just use a pad mounted whole house generator. When power goes out, your lkife goes on normally and you get to enjoy looking outside and watch your neighbors suffer. Use batteries and you and your wallet will be the one suffering.

[NetComrade]

I do have 2, Solaredge 3800 and SolarEdge 6000.
Teslas' you can't really buy, but good to know any SolarEdge inverter is compatible with powerwall 2.
"AC coupled" rings a bell... Will the mentioned Outback "fool" the SolarEdge they're connected to the grid?

I will also research what "bi-modal" means

[ButchDeal]

ok, thanks.. sounds the only other route (especially if I want to maintain remote monitoring of solaredge) is to install a 3rd hybrid inverter and tap into the 400V+ DC lines coming off the roof.

I don't understand what you mean by "Third"
you have only one inverter now the SE3800.
you can AC couple with a bimodal inverter like from OutBack power, but trying to "tap" into the DC bus on the SolarEdge network is not a good idea and not likely to work anyway. You would void all warranties and have to come up with a charging solution from the 350-450V DC bus to your battery.

The other route it to swap a solaredge with a one that supports the Tesla battery, but seems like that never really shipped.

The SolarEdge SE7600 supports the powerwall V1
any solarEdge inverter should support the powerwall V2

or you could use the existing solaredge with an outback in an AC coupled fashion

[NetComrade]

ok, thanks.. sounds the only other route (especially if I want to maintain remote monitoring of solaredge) is to install a 3rd hybrid inverter and tap into the 400V+ DC lines coming off the roof.

The other route it to swap a solaredge with a one that supports the Tesla battery, but seems like that never really shipped.

[SunEagle]

I thought of using a very small battery bank, to last let's say 30m worth of energy to give enough time to start the generator.

I am sure you can build a small UPS system that will carry you through a power outage until the gen set starts up. Based on cost I would charge it back up from the grid or from the generator instead of using the solar panel system. The cost of that type of charger probably would not pay for itself unless you get a lot of power outages.

[NetComrade]

I thought of using a very small battery bank, to last let's say 30m worth of energy to give enough time to start the generator.