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Are there any budget hybrid grid tie inverters that actually work?

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Solar Wizard
Joined
Feb 1, 2023
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I've decided on a grid parallel hybrid setup that powers the main panel in connection with the grid but doesn't export to the grid. There are solutions out there!

I would love to get a solark, or a Schneider ,or victron, but their price kills my ROI(my per kWh price is currently 13.2cents)

So I look at the megarevos and sungolds etc and it's horror story after horror story.

So, is there anything affordable that actually works? Or do I need to wait a year or three for the kinks to get worked out?
 
So, is there anything affordable that actually works?
So you are looking at original purchase price of the first unit as your measure of what is "affordable"?

I've said it before, i cannot afford to buy crappy electronic equipment, particularly SCCs. I have an SCC that i bought in 2010 working every day and showing no sign of letting up. Had i bought an "affordable" one, it'd probably be on my third or forth.
 
So you are looking at original purchase price of the first unit as your measure of what is "affordable"?

I've said it before, i cannot afford to buy crappy electronic equipment, particularly SCCs. I have an SCC that i bought in 2010 working every day and showing no sign of letting up. Had i bought an "affordable" one, it'd probably be on my third or forth.
I think we are saying the same thing. I don't want to buy something that won't work, but it doesn't make financial sense (currently) to buy something that will work but is a net money loser, and there doesn't appear to be a happy medium currently
 
(my per kWh price is currently 13.2cents)
If you are looking to beat this penny for penny, you'd be very lucky. In California, we're trying to beat $.45/kWh which is far easier but still challenging.

If you are looking to come out ahead with peace of mind for backup power, hedging against future rate increases and the likes, then buying quality equipment is your best bet.
 
If you are looking to beat this penny for penny, you'd be very lucky. In California, we're trying to beat $.45/kWh which is far easier but still challenging.

If you are looking to come out ahead with peace of mind for backup power, hedging against future rate increases and the likes, then buying quality equipment is your best bet.
At .45/kWh, i would achieve payback in 3 years lol. I think my advantage is I'm not paying an install service 3x the cost to do it for me, plus 20% on top of that for financing charges.
 
If you are looking to beat this penny for penny, you'd be very lucky. In California, we're trying to beat $.45/kWh which is far easier but still challenging.

If you are looking to come out ahead with peace of mind for backup power, hedging against future rate increases and the likes, then buying quality equipment is your best bet.
Which hybrid inverter do you use?
 
Here is my Outback Skybox 15kwh system in action, on PG&E EV rates with much higher rates from 3-4, 4-9, 9-12am so I just program the Skybox to self supply from 4-12am. Most I have used is around 12khW at 12am so I am building another battery pack of 16 x 280ah batteries and that should ride through to 8am for the solar to start charging again. Of course I won't cycle the battery from 12am-8am but i will have enough if the grid does go down. Note I am not trying to conserve power from 4-12 and I am just using the house as I would on-grid.
Snip20230221_6.png
Another view from Enlighten which is AC coupled to the Skybox on the backup loads side. It doesn't know about the DC array and power generated from that so the graphs are a little wonky. The Grid import and Grid export is pretty close to what Skybox reports.
IMG_2099.PNG
 
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I've decided on a grid parallel hybrid setup that powers the main panel in connection with the grid but doesn't export to the grid. There are solutions out there!
Noticed your OP on Thurs didn't comment at that time, you are still interested so wanted to point out that your stated goal of feeding power into the main panel vs. installing a critical loads subpanel is somewhat at odds with the terms, budget, short pay-back period and cost effectiveness because the main panel carries a large load in comparison to what a single inverter can provide. Also the terminology in your OP needs to be clarified.

"Grid parallel, hybrid set up" is a bit of an oxymoron. Grid-tied inverters can be described as being connected in "parallel" with regard to the bus bars in a load panel in the sense that the grid as well as the grid-tied pv system can both supply power to the branch breakers thus the loads. A hybrid inverter on the other hand has AC Input and AC Output terminals. If you wish to connect the Inverter AC Output to the main panel then the wires on the main breaker in that panel have to be intercepted, generally by a Transfer Switch, so Power from the utility meter is fed directly into the Inverter AC Input. This configuration would be more appropriately described as a Series connection since any grid power used would be feeding through the inverter then to the loads. When the grid is down or you wish to use Load Shaving then the inverter feeds the main panel using batteries to carry the load.
The problem with connecting the main panel to a single inverter is:
1) Total amount of power in pass thru mode is limited to the rating of the inverter built in transfer/disconnect switch which is 40A to 60A only. Which may be enough for your house (it is for ours) but probably would not be code compliant because a 100A main breaker is considered the minimum.
2) Total amount of power when in PV/inverter mode is even more limited to the inverter output rating and ability to start inductive loads which is quite poor with a budget type inverter.

If you are serious about wanting to do a DIY solar project with a budget in mind, it would be advisable to consider installing a critical loads subpanel connected to something like an All-in-One EG4 6000EX that has split phase capability without the need for a second inverter or autotransformer.
 
I've decided on a grid parallel hybrid setup that powers the main panel in connection with the grid but doesn't export to the grid. There are solutions out there!

I would love to get a solark, or a Schneider ,or victron, but their price kills my ROI(my per kWh price is currently 13.2cents)

So I look at the megarevos and sungolds etc and it's horror story after horror story.

So, is there anything affordable that actually works? Or do I need to wait a year or three for the kinks to get worked out?
I really need to get around to typing up a review of my SGP TP6048, not a horror story by any means.
 
Which hybrid inverter do you use?
I currently only have micro inverters.
I am patiently waiting for the next generation of DIY friendly, UL compliant inverter.
Becoming less and less patient.
My critical loads panel and 48V 280Ah battery are ready too.
 
Here is my Outback Skybox 15kwh system in action, on PG&E EV rates with much higher rates from 3-4, 4-9, 9-12am so I just program the Skybox to self supply from 4-12am. Most I have used is around 12khW at 12am so I am building another battery pack of 16 x 280ah batteries and that should ride through to 8am for the solar to start charging again. Of course I won't cycle the battery from 12am-8am but i will have enough if the grid does go down. Note I am not trying to conserve power from 4-12 and I am just using the house as I would on-grid.
View attachment 136032
Another view from Enlighten which is AC coupled to the Skybox on the backup loads side. It doesn't know about the DC array and power generated from that so the graphs are a little wonky. The Grid import and Grid export is pretty close to what Skybox reports.
View attachment 136036
Thanks for posting that. I can find any info on a 15k skybox online.

Also are you using a critical loads panel or main panel? Thanks
 
Noticed your OP on Thurs didn't comment at that time, you are still interested so wanted to point out that your stated goal of feeding power into the main panel vs. installing a critical loads subpanel is somewhat at odds with the terms, budget, short pay-back period and cost effectiveness because the main panel carries a large load in comparison to what a single inverter can provide. Also the terminology in your OP needs to be clarified.


That's exactly why I want to use the main panel. To power large loads. I don't use a terrible amount of power. About 2.5kwh and a 6kw system would be ideal for me in but someone could be taking a shower with the water heater using 4.5kw and my well pump could come on with an inrush of 37 amps and with the right circumstances, shut an off grid inverter down. With grid tied hybrid they can't happen.
"Grid parallel, hybrid set up" is a bit of an oxymoron. Grid-tied inverters can be described as being connected in "parallel" with regard to the bus bars in a load panel in the sense that the grid as well as the grid-tied pv system can both supply power to the branch breakers thus the loads. A hybrid inverter on the other hand has AC Input and AC Output terminals.


Wouldn't that just be an off grid inverter?
If you wish to connect the Inverter AC Output to the main panel then the wires on the main breaker in that panel have to be intercepted, generally by a Transfer Switch, so Power from the utility meter is fed directly into the Inverter AC Input. This configuration would be more appropriately described as a Series connection since any grid power used would be feeding through the inverter then to the loads. When the grid is down or you wish to use Load Shaving then the inverter feeds the main panel using batteries to carry the load.
The problem with connecting the main panel to a single inverter is:
1) Total amount of power in pass thru mode is limited to the rating of the inverter built in transfer/disconnect switch which is 40A to 60A only. Which may be enough for your house (it is for ours) but probably would not be code compliant because a 100A main breaker is considered the minimum.
2) Total amount of power when in PV/inverter mode is even more limited to the inverter output rating and ability to start inductive loads which is quite poor with a budget type inverter.

If you are serious about wanting to do a DIY solar project with a budget in mind, it would be advisable to consider installing a critical loads subpanel connected to something like an All-in-One EG4 6000EX that has split phase capability without the need for a second inverter or autotransformer.
My understanding of a hybrid inverter is one that is grid tied with battery backup. In my case I also want zero export. My understanding is that what you described can be done with a simple off grid inverter.
Please correct me if I'm wrong
 
Thanks for posting that. I can find any info on a 15k skybox online.

Also are you using a critical loads panel or main panel? Thanks
The skybox is only 5kw of inverting power but because I have CTs installed at main panel and it is a grid tied inverter, it can push power back through the grid feed to net out whole house consumption.
 
The skybox is only 5kw of inverting power but because I have CTs installed at main panel and it is a grid tied inverter, it can push power back through the grid feed to net out whole house consumption.
Oh ok, 5k not 15k(mistype I think).
That's exactly what I need to be able to do but without ever exporting to the grid. Im watching videos on the skybox now
 
My understanding of a hybrid inverter is one that is grid tied with battery backup. In my case I also want zero export. My understanding is that what you described can be done with a simple off grid inverter.
Please correct me if I'm wrong
You are not wrong, its that you have a mental concept that seems simple but in reality requires a combination of hardware and firmware/software that is generally only found on the more expensive, full featured inverters Schneider, Sol-Ark, maybe the new Outback Mojave system. What you are describing are a set of features such as Grid Support, Peak Load Shave & Generator Support all of which require the inverter to be active while grid (or Gen) power is passing through the inverter. As your household loads change the inverter is trying to react rapidly to partially supply power to loads but not so much that some leaks backwards out to the grid. That's NOT simple at all.

Budget priced inverters operate in fixed modes such as SBU, USB or SUB. For example during the day when there is plenty of solar and the batteries are charged you can run off the inverter but when your water heater and well pump turn on at the same time the inverter will overload and shutdown. They are not capable of seamlessly "blending" power from the grid and inverter at the same time. In addition they are a poor choice for inductive loads like air conditioning and pumps.

To be clear, I'm not trying to talk you out of whole house backup, just trying to keep you from being disappointed by a low cost system that doesn't keep you comfortable.
Our 1,900 sq ft house (200A main panel) is at this very moment is running on a single Schneider XW+ 6848 being fed with a 60A, 2 pole breaker. When the grid goes down, we really don't have to worry about anything or run around turning things off including the 4 ton AC unit. So what you are proposing can most certainly be done IF designed and installed correctly.
 
You are not wrong, its that you have a mental concept that seems simple but in reality requires a combination of hardware and firmware/software that is generally only found on the more expensive, full featured inverters Schneider, Sol-Ark, maybe the new Outback Mojave system. What you are describing are a set of features such as Grid Support, Peak Load Shave & Generator Support all of which require the inverter to be active while grid (or Gen) power is passing through the inverter. As your household loads change the inverter is trying to react rapidly to partially supply power to loads but not so much that some leaks backwards out to the grid. That's NOT simple at all.

Budget priced inverters operate in fixed modes such as SBU, USB or SUB. For example during the day when there is plenty of solar and the batteries are charged you can run off the inverter but when your water heater and well pump turn on at the same time the inverter will overload and shutdown. They are not capable of seamlessly "blending" power from the grid and inverter at the same time. In addition they are a poor choice for inductive loads like air conditioning and pumps.

To be clear, I'm not trying to talk you out of whole house backup, just trying to keep you from being disappointed by a low cost system that doesn't keep you comfortable.
Our 1,900 sq ft house (200A main panel) is at this very moment is running on a single Schneider XW+ 6848 being fed with a 60A, 2 pole breaker. When the grid goes down, we really don't have to worry about anything or run around turning things off including the 4 ton AC unit. So what you are proposing can most certainly be done IF designed and installed correctly.
I appreciate the clarification and I agree. At this time the budget hybrid inverters like the megarevo 8k don't seem to be there in terms of reliability. So it looks like I'm going to have to pony up for a better inverter.

My thought for backup would be to also feed the ac out of the inverter to the main panel but use an interlock where it can never be on at the same time as the main breaker. That way if grid goes out I flip the interlock and the main panel has now become the backup panel. I know, it sounds radical but I don't see why it wouldn't work.
 
...

My understanding of a hybrid inverter is one that is grid tied with battery backup...
There is no perfectly accepted definition for 'hybrid". Some people insist it must only applied to solar inverters that are grid tied with a battery backup when grid is not available or for purposes of time shifting loads to take advantage of differing grid rates. Quite a few others use "hybrid" to mean it can supply loads either by grid or inverter with UPS like fallback.

The problem with grid tied setups is that even if you do so called zero export you need an interconnect agreement with your utility company. For good reason because any power sources in parallel are never truly isolated from each other. In order to pick up load from one you must decrease the loading on the other. The costs of getting your utility approval of this can easily blow a budget.
 
There is no perfectly accepted definition for 'hybrid". Some people insist it must only applied to solar inverters that are grid tied with a battery backup when grid is not available or for purposes of time shifting loads to take advantage of differing grid rates. Quite a few others use "hybrid" to mean it can supply loads either by grid or inverter with UPS like fallback.

The problem with grid tied setups is that even if you do so called zero export you need an interconnect agreement with your utility company. For good reason because any power sources in parallel are never truly isolated from each other. In order to pick up load from one you must decrease the loading on the other. The costs of getting your utility approval of this can easily blow a budget.
At first I didn't want to deal with the utility so I was considering an off grid system with a switch but the more I looked into it the more it made sense to do a grid tied system. Lucky for me the only cost is a stamped design and that's about $400.


The zero export thing is because , in addition to paying peanuts for received power ,they charge you an additional monthly fee for having a solar plan and regular rates. If I do a non solar tou plan I can buy energy from the grid at night for 9c /kwh
 
Do it. Are you using it as an off grid inverter, or as a grid tied inverter?
Grid tied, zero export. Attached a bunch of SA data showing how it functions.
Ill work on a writeup...
 

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Grid tied, zero export. Attached a bunch of SA data showing how it functions.
Ill work on a writeup...
Nice!!!

The third image is beautiful to me lol.

To clarify. You just have the grid line hooked up to your main panel and that line carries power bidirectionally to/from the main panel and you use cts to control import/export?
 
Nice!!!

The third image is beautiful to me lol.

To clarify. You just have the grid line hooked up to your main panel and that line carries power bidirectionally to/from the main panel and you use cts to control import/export?
No cts. Attached diagram should explain how I have it wired.
 

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No cts. Attached diagram should explain how I have it wired.
Oh snap I was getting excited there for a minute.
The way you have it hooked up is pretty much off grid mode and you're limited to 6kw of power delivery at any time.

Thanks for sharing though
 
if you have a backup loads panel and pushing power back through grid input to main panel, it is very hard/impossible to prevent leaking back out to grid even though you have CTs installed due to all the reason people have outlined above. If you put the whole house behind the inverter like the solark 15k, you can prevent any power from being exported back to grid.
 
if you have a backup loads panel and pushing power back through grid input to main panel, it is very hard/impossible to prevent leaking back out to grid even though you have CTs installed due to all the reason people have outlined above. If you put the whole house behind the inverter like the solark 15k, you can prevent any power from being exported back to grid.
I understand that.

The part I don't understand about putting the whole house behind the inverter is, if there is a load too great for the solar panels or battery, does it switch completely to grid, or just blend enough grid in to power the load.
 

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