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Is there a grid tie system that can be easily switched to non-grid tied?

IP4

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I'm in the US and would like to use solar even if the grid goes down while using a grid-tied system.

I'd like to get the cost savings of feeding the grid while the grid is up, but if the grid goes down I want to be able to use the solar to charge my batteries. I'm not concerned about a failover where there's no time delay between switching from grid to non-grid if the grid goes down. I could do that manually when needed. The main goal is to use my solar panels for whatever I want if the grid goes down.

The only way I can think of is to have a second charger/inverter where I manually take the wires that come from the solar panels and feed into the grid-tied inverter, and move them over to the non-grid tied charger/inverter. But this would be quite expensive.

Is there a way to do this without a second non-grid charger/inverter?
 
IP4, It sounds like your goals are similar to mine.

I am new to all the lingo and norms and what not but I think what you are looking for is called "Hybrid Solar (grid tied with battery backup)".

There are multiple Hybrid Inverter providers out there though if you are in the US and looking to tie to the grid and/or are in a juridiction with heavy compliance mandates you likely will need to go with a UL listed Hybrid Inverter (and may want to factor in standby efficiency etc).

At this point I am looking to go with the Sol-Ark Hybrid inverter (12K unless the 15K comes really soon).

If I understand things correctly I plan to mainly keep my batteries mostly charged and available for myself if the grid goes down and will feed any excess power to the grid during the day and then pull from the grid after solar production stops (treating the grid kinda like a battery)... My power company allows that but does not pay me for any overage and I don't think I will have any as I use way more energy that my solar setup will produce. My design is basically enough solar and battery backup to provide power to my critical loads like:

- 2 refrigerators & 1 freezer (all 120V on 2 different circuits);
- Septic aerator & pump (240V & not sure specs);
- Pool pump (240V single speed 1.5HP);
- Garage Door (120V);
- Multiple circuits for lights/outlets for parts of my home (all 120V) & particularly a safe zone of my house;
- Efficient mini-split AC+Heat Pump (220V) for a safe zone of my house (my master bedroom, master office, master bath, & saferoom);
- 1 washer (120V);
- 1 electric water heater (240V) (that I may switch off if batteries are low);

I may also add my electric dryer (240V) or something like that as an on demand dump load... Note that I have conventional multistage 5ton and 3ton AC+Heatpumps and large electric stoves/ovens/etc that I do not plan to run through the Sol-Ark... I already added propane for heat and emergency cooking and do plan to get a plugin induction cooktop if I have excess solar production (batteries full) when the grid is down.

If my memory is correct (and I understand correctly) I am planning on putting on the Sol-Ark's load output to 2 critical loads panels such that each individual critical circuit can be manually switched between the SolArk and the grid such that if there is any issue with my SolArk system I can easily be back on grid while it is fixed (hopefully something like the following):

http://www.reliancecontrols.com/ProductDetail.aspx?A510C
 
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IP4, It sounds like your goals are similar to mine.

I am new to all the lingo and norms and what not but I think what you are looking for is called "Hybrid Solar (grid tied with battery backup)".

There are multiple Hybrid Inverter providers out there though if you are in the US and looking to tie to the grid and/or are in a juridiction with heavy compliance mandates you likely will need to go with a UL listed Hybrid Inverter (and may want to factor in standby efficiency etc).

At this point I am looking to go with the Sol-Ark Hybrid inverter (12K unless the 15K comes really soon).

If I understand things correctly I plan to mainly keep my batteries mostly charged and available for myself if the grid goes down and will feed any excess power to the grid during the day and then pull from the grid after solar production is down (treating the grid kinda like a battery)... My power company allows that but does not pay me for any overage and I don't think I will have any as I use way more energy that my solar setup will produce. My design is basically enough solar and battery backup to provide power to my critical loads like:
- Septic aerator & pump (240V & not sure specs);
- Pool pump (240V single speed 1.5HP);
- 1 electric water heater (240V) (that I may switch off if batteries are low);
- 1 washer (120V);
- Garage Door (120V);
- 2 refrigerators & 1 freezer (all 120V on 2 different circuits);
- Multiple circuits for lights/outlets for parts of my home (all 120V) & particularly a safe zone of my house;
- Mini-split AC Heat Pump (220V) for a safe zone of my house (my master bedroom, master office, master bath, & saferoom);

I may also add my electric dryer (240V) or something like that as an on demand dump load... Note that I have conventional multistage 5ton and 3ton AC+Heatpumps and electric stove/oven/etc that I do not plan to run through the Sol-Ark when the grid is down...

If my memory is correct (and I understand correctly) I am planning on putting on the Sol-Ark's load output 2 critical loads panels that can be switched between the SolArk and the grid like the following:

http://www.reliancecontrols.com/ProductDetail.aspx?A510C
Thanks! I'm new to this too and it's good to find out that other people have thought of this and have solutions. Sol-Ark seems like a good company and they have good reviews so I'll keep them in mind. The switch is clever as well.
 
There are numerous options to get back up power and backfeed the grid for net metering.

All require a battery (there may be some enphase micro inverters that cab power lights, etc) and some way to disconnect from the grid.

There is tons of information on the forum. You've got lots of reading ahead of you.

If you want to run you AC or anything with a large motor, I'd recommend a low frequency inverter. A high frequency inverter, like the Sol-ark, is not good at the high surge required to start a motor.
 
Thanks! I'm new to this too and it's good to find out that other people have thought of this and have solutions. Sol-Ark seems like a good company and they have good reviews so I'll keep them in mind. The switch is clever as well.
No problem. Hopefully if I said anything incorrectly above some of the most knowlegeable folk on this forum will correct it.

The SolArks are higher priced than I was hoping but after learning more about UL listing and efficiencies (standby/idle and otherwise) and considering this solution is for my home with the safe room for my kids and my home office so I can still do my work when the grid is down I decided to not try to be penny-wise and pound-foolish. I would be devastated if my home burned down and my insurance company denied my claim due to using non UL listed equipment.
 
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The SolArks are higher priced that I was hoping but after learning more about UL listing and efficiencies (standby and otherwise) and considering this solution is for my home with the safe room for my kids and my home office so I can do my work I decided to not try to be penny-wise and pound-foolish. I would be devastated if my home burned down and my insurance company denied my claim due to using non UL listed equipment.
There are lots of other options for tier 1 components that have a long history of reliable service and are UL listed.
The Sol-ark is a rebranded 3rd party inverter.
 
I'm in the US and would like to use solar even if the grid goes down while using a grid-tied system.

I'd like to get the cost savings of feeding the grid while the grid is up, but if the grid goes down I want to be able to use the solar to charge my batteries. I'm not concerned about a failover where there's no time delay between switching from grid to non-grid if the grid goes down. I could do that manually when needed. The main goal is to use my solar panels for whatever I want if the grid goes down.

The only way I can think of is to have a second charger/inverter where I manually take the wires that come from the solar panels and feed into the grid-tied inverter, and move them over to the non-grid tied charger/inverter. But this would be quite expensive.

Is there a way to do this without a second non-grid charger/inverter?

Enphase iQ8 and SMA Sunny Boy are grid-tied inverters that can also provide power when the grid is town.
 
By definition a hybrid inverter can operate as a grid tie inverter and with the addition of batteries can operate off grid. They often contain automatic transfer switches. The additional circuitry to do all of the above is why they are more expensive than simple GT inverters.

GT inverters are simpler and presumably produced in greater volumes than hybrid inverters. Those are what account for their less expensive price points.
 
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