Backup "reconfiguration" solution to current AC-Coupled system for DR

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I was researching potential cost-effective off-grid backup PV solutions in the event of a long-term Disaster (recovery).

I currently have a 5KW AC-coupled (microinverter) setup with batteries: no backup, self-consumption only. Panels are JA Solar 355-JAM6(K)72-355/PR (Voc 47.5, Isc 9.69). It isn't cost effective for me to rollout the required switch/controller and MPU for a true whole home backup. What I want is a quick, off-grid, "backup" controller solution in the event of a major disaster . . . with a predicted prolonged service outage.

So I wanted to procure a solar charge controller/inverter that I could reconfigure and reconnect my existing solar panels to and then charge a battery bank.

Looking for most efficient recommended cost-effective configuration with an MPPT charge controller and PV array setup (Series/Parallel) and battery bank setup (12/24/48V). Maybe someone's personal preferences on a Solar Charge controller, inverter, or combo as well as most efficient design. I found the Outback Flexmax 80 FM80 MPPT 80 AMP Solar Charge Controller for ~$450 and it seems like a good purchase and I have a 12v 1KW inverter. Trying to minimize cost and leverage what I have. I also have a few MC4 combiner (parallel) connectors and some feeders as well as the battery cables for either series or parallel. Hoping to only expense the controller and or controller/inverter combo as this is designed for a disaster scenario only. Note, I do have a good 7K inverter generator but limited fuel storage capacity (~3-4 days max)

Thanks in advance
 
How do you propose to use a charge controller with microinverters?
 
ggunn said:
How do you propose to use a charge controller with microinverters?
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That part I understand. In the "reconfiguration" I would disconnect the microinverters and string the PV modules together in parallel or series, depending on recommendations. I imagine to reconfigure this from an AC-coupled grid-tied system to an off-grid DC /inverter system would take me a couple of hours of re-cabling. Again, this would be in a DR scenario only (in SoCal)
 
LATTC Student said:
That part I understand. In the "reconfiguration" I would disconnect the microinverters and string the PV modules together in parallel or series, depending on recommendations. I imagine to reconfigure this from an AC-coupled grid-tied system to an off-grid DC /inverter system would take me a couple of hours of re-cabling. Again, this would be in a DR scenario only (in SoCal)
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Is 1kW backup power worth all that trouble?

I suggest you spend the money on a conversion kit for your generator and run it off natural gas for long blackouts. It's much cleaner than gas and very low probability of running out of fuel.
 
analog8484 said:
Is 1kW backup power worth all that trouble?

I suggest you spend the money on a conversion kit for your generator and run it off natural gas for long blackouts. It's much cleaner than gas and very low probability of running out of fuel.
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Good point for 1KW. I would most likely welcome ideas to get q cost-effective solar charger/inverter combo ~4KW. I do like the natural gas idea but the DR scenario assumption is an all-service outage - earthquake country around here.
 
It's sounding more and more like what I am asking for is basically deploying an entirely additional system for off-grid. I guess that's really overkill. I have an old 400W Renogy kit in my shed that could get me by in a disaster for a while, coupled with the generator. This isn't exactly the "Doomsdayer" forum . . .which is now how I feel this post is about (and which I am not). So thanks again Analog and ggunn for bringing some common sense into it for me.
 
Dual fuel with propane option is nice IF you already have a propane tank instead of piped natural gas.
If you really want SHTF provisioning and have tons of money to spare get a Schneider Hybrid Inverter with Generator Support when in off grid operation. All you have to add is a charge controller. Look at Midnight Solar for ultra reliable and feature filled. Use a diesel generator for best long term fuel storage. The Inverter can be set up to keep generator loading above 50% to prevent "wet stacking". Turning generator on and off as needed to balance generator running with battery use.
If you have a site suitable for year-round hydro power you are golden.
But with all that, self defense becomes a serious issue.

How's that for a comprehensive short summary?
 
If you just want to charge your phones, consider a cheap inverter and car battery type setup that you can unplug a single panel from you array to power. Look for something made for RVs.

To keep the fridge running, nothing will be more cost effective than adding an Enpower to your system.
 
GoldDigger said:
Dual fuel with propane option is nice IF you already have a propane tank instead of piped natural gas.
If you really want SHTF provisioning and have tons of money to spare get a Schneider Hybrid Inverter with Generator Support when in off grid operation. All you have to add is a charge controller. Look at Midnight Solar for ultra reliable and feature filled. Use a diesel generator for best long term fuel storage. The Inverter can be set up to keep generator loading above 50% to prevent "wet stacking". Turning generator on and off as needed to balance generator running with battery use.
If you have a site suitable for year-round hydro power you are golden.
But with all that, self defense becomes a serious issue.

How's that for a comprehensive short summary?
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Love it! Yeah, should be more focused on laying dormant minefield in my perimeter and stocking up on .308 for the Zombie waves, LOL
 
jaggedben said:
If you just want to charge your phones, consider a cheap inverter and car battery type setup that you can unplug a single panel from you array to power. Look for something made for RVs.

To keep the fridge running, nothing will be more cost effective than adding an Enpower to your system
Click to expand...
Makes sense, thanks JB. I will just save up for that as next phase. It was more the MPU cost that was the deterrent. I have a (commercial electrician) friend who offered to do it for a good price.
 
LATTC Student said:
It's sounding more and more like what I am asking for is basically deploying an entirely additional system for off-grid. I guess that's really overkill. I have an old 400W Renogy kit in my shed that could get me by in a disaster for a while, coupled with the generator. This isn't exactly the "Doomsdayer" forum . . .which is now how I feel this post is about (and which I am not). So thanks again Analog and ggunn for bringing some common sense into it for me.
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If Doomsday scenario is what you are concerned about then getting some power from your solar array is far from adequate. If the situation is so bad that natural gas lines are disrupted for a long time then water supply lines are likely gone too. What will you do for water, food, heating, cooking, transport? If you are serious about this stuff then you should check the prepper sites to see what they do. Real prepping gets expensive quickly. Personally, I don't think it's practical worrying about outages longer than a couple weeks. Beyond that duration many other things besides power become real problems and it would be bugout time for me.
 
analog8484 said:
If Doomsday scenario is what you are concerned about then getting some power from your solar array is far from adequate. If the situation is so bad that natural gas lines are disrupted for a long time then water supply lines are likely gone too. What will you do for water, food, heating, cooking, transport? If you are serious about this stuff then you should check the prepper sites to see what they do. Real prepping gets expensive quickly. Personally, I don't think it's practical worrying about outages longer than a couple weeks. Beyond that duration many other things besides power become real problems and it would be bugout time for me.
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Yes all true. We do have some of that stuff but I am certainly not a prepper. We have 60 gal's of gas, 10X5gal of bottled spring water, a survival suitcase from Costco, 10 boxes or Army MRE, guns/ammo, generator, and the 400W off grid Renogy solar kit. Survivable, maybe. Those things were all just sort of accumulated over the years. The power outage (maybe from cyber, natural disaster, or other). Those threats aren't on my mind frequently but I did want to leverage my existing solar for a prolonged outage, if possible.

At this point I think Ben's idea of just biting the bullet and adding the whole home backup switch for $3K will be my next expense. I do like the alternate propane/natural gas option for long term on fuel for the gen as well. Just need to investigate cost.

Thanks again for the follow ups Analog. Lots of good perspective in this group.
 
LATTC Student said:
Good point for 1KW. I would most likely welcome ideas to get q cost-effective solar charger/inverter combo ~4KW. I do like the natural gas idea but the DR scenario assumption is an all-service outage - earthquake country around here.
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Good point. Much of SoCal has had seismic shut-offs put inline with the meter and disaster response will have many gas mains shutdown, with reopening gas mains starting at emergency services such as hospitals, fire and police departments, and military/national guard bases before residential service is restarted.
 
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