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Is grid connectivity inverter really worth it?

Alkaline

Solar Wizard
Joined
Jul 26, 2020
Messages
2,065
Location
Orange, Tx
The inverters that have grid connectivity, are they worth having? If you are never planning on selling back to the utility company but instead just have a transfer switch / sub panel to power your house?

The price difference is substantial, so if you are not planning on connecting to the grid should you still get a on-grid inverter?
 
If you don't want to sell back, you can still offset your grid usage. No need for transfer switches if that is the goal. If you are not going to be connected to the grid at all, then no, you don't need it.
 
The inverters that have grid connectivity, are they worth having? If you are never planning on selling back to the utility company but instead just have a transfer switch / sub panel to power your house?

The price difference is substantial, so if you are not planning on connecting to the grid should you still get a on-grid inverter?
It's grid assist they want so they can start up larger loads. Usually the battery bank can't handle the surge.

Some of these people must have 20 HP motors in their basement running a line drive as I can't fathom needing that much power in a residential house. I can easily run anything in my house. We just don't run everything at once.

My shop is another matter, motors of all sizes to start/run. There is a way around that too and run strictly off solar.
 
I have my own version of grid assist.
A Chargeverter.
I love mine. Only argument would be that it depends on just how much grid assist you need.

IE, you want to run a big welder or (insert large load here) that your inverter can’t handle.

That’s getting a bit beyond the scope of the question, but I do think it’s worth noting you have to look at turn key cost of either setup. Regular inverter + chargeverter may begin approaching cost of the inverter you were trying to avoid in the first place.
 
I have my own version of grid assist.
A Chargeverter.
Did they ever make it so it can be set to a certain float voltage and be left there? I wouldn't necessarily want it to charge my batteries to full if left alone, just hold the line so to speak.
 
It's grid assist they want so they can start up larger loads. Usually the battery bank can't handle the surge.

Some of these people must have 20 HP motors in their basement running a line drive as I can't fathom needing that much power in a residential house. I can easily run anything in my house. We just don't run everything at once.

My shop is another matter, motors of all sizes to start/run. There is a way around that too and run strictly off solar.
You must not be married.

I just replaced a perfectly good electric dryer with a gas version, simply so I didn’t have to break down the how/why for my wife.

Clearance price $400 LG with smart features felt cheaper an easier. Hell I’d happily spend $400 to avoid the look on her face when I say to only dry clothes at certain times ;)
 
You must not be married.

I just replaced a perfectly good electric dryer with a gas version, simply so I didn’t have to break down the how/why for my wife.

Clearance price $400 LG with smart features felt cheaper an easier. Hell I’d happily spend $400 to avoid the look on her face when I say to only dry clothes at certain times ;)

Just hook up an inverter and batteries right next to the electric drier, with a battery meter on it. Tell her she can run the dryer until the battery meter goes to zero. :ROFLMAO:
 
Did they ever make it so it can be set to a certain float voltage and be left there? I wouldn't necessarily want it to charge my batteries to full if left alone, just hold the line so to speak.
It's always been that way.
That's how I use it. (Or will, if I ever need to)
 
I love mine. Only argument would be that it depends on just how much grid assist you need.

IE, you want to run a big welder or (insert large load here) that your inverter can’t handle.

That’s getting a bit beyond the scope of the question, but I do think it’s worth noting you have to look at turn key cost of either setup. Regular inverter + chargeverter may begin approaching cost of the inverter you were trying to avoid in the first place.
I don't need it for surges. Although it would help for that if the battery is low.
 
The inverters that have grid connectivity, are they worth having? If you are never planning on selling back to the utility company but instead just have a transfer switch / sub panel to power your house?

The price difference is substantial, so if you are not planning on connecting to the grid should you still get a on-grid inverte
I'm off grid, I bought a Hybrid. Mostly for the 10 year warranty with us support. I have not seen any off grid all in 1 inverters out there that offer that. I'm sure some one can find one may be that would be the one you get.
 
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It's grid assist they want so they can start up larger loads. Usually the battery bank can't handle the surge.

Some of these people must have 20 HP motors in their basement running a line drive as I can't fathom needing that much power in a residential house. I can easily run anything in my house. We just don't run everything at once.

My shop is another matter, motors of all sizes to start/run. There is a way around that too and run strictly off solar.
I’d like to run a 50 Amp plasma cutter and a 5 hp air compressor plus other loads at the same time in my shop. Or a 20 inch planner and 3 hp dust collector. I’d take grid pass through if I could get it.

I am hoping my 4x Sunny Islands will pass through a good chunk of the 100 Amps from my 25KW generator. Still unclear on how much it will do so. I don’t mind running the generator for the occasional job.

On the plasma cutter part, if I find myself using it a bunch, I’ll probably buy a Hypertherm 30 Air which the Sunny Islands should have no problems with on their own.
 
GT PV is the simplest and cheapest system.
If net metering is available, that is cheaper than batteries, more efficient, and has vastly more capacity.
Even if you receive zero credit, being allowed to backfeed simplifies system. You can over-panel with cheap PV panels and throw away power you don't use.

Without some sort if credit, you probably want batteries. But just 25% credit and you're better off buying more panels and forgoing battery.

If your grid connection is 200A, you've got 48kW available and almost 250kW for motor starting surge.
It would take a lot of battery and inverter to come close to that.

But it does depend on your application, purpose, loads.

Between off-grid and grid-interactive, price difference could be some sensors and firmware. Beyond that, quality and certifications. Maybe recovering cost of more extensive UL testing is the primary thing you're paying for but don't need.

If not backfeeding at all, do like I do and buy old model Sunny Islands and Sunny Boys at liquidation prices. At least for larger systems; small ones can be built cheaper with other brands.
 
Since I have net metering, I went with 2 separate systems. I use the off grid system as much as I can and build up my kwh bank on the grid for cloudy days. The downside is 9kw of PV going unused when the grid is down. If I could start over, I'd probably get a hybrid inverter and let those 29 solar panels on the roof be available whenever I want them.
 
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