Swap Solis inverter (non hybrid) for a hybrid so can add batteries

[bignose2]

Hi,

I really hope you can advise as to be honest most installers are asking quite a lot of money & not really advising of what is involved.

Last year I had 3.6 Solis grid tied (non-hybrid) inverter (4.2 PV) installed

All works well but no batteries then.

I would like to add batteries so I think the easiest (slightly more expensive) way would be to swap for a hybrid.

Do you know if the connections are basically the same (apart from the batteries obviously) & maybe more data, CT etc. but non-Grid stuff.

From what I can see from the manuals the Hybrid has the same connections as the non-hybrid

It seems still a single main power Grid cable into the CU which I assume must be standard into the meter, all isolations as already installed etc. The meter seems to have Imp & Exp written on it : EML M22. ECA2.v v1

I just cannot see how anything extra would be physically required on the grid side.

Could I just disconnect the old inverter & replace with a hybrid & connect the batteries.

Thanks I/A

 

[johnb2713]

Hi,

I really hope you can advise as to be honest most installers are asking quite a lot of money & not really advising of what is involved.

Last year I had 3.6 Solis grid tied (non-hybrid) inverter (4.2 PV) installed

All works well but no batteries then.

I would like to add batteries so I think the easiest (slightly more expensive) way would be to swap for a hybrid.

Do you know if the connections are basically the same (apart from the batteries obviously) & maybe more data, CT etc. but non-Grid stuff.

From what I can see from the manuals the Hybrid has the same connections as the non-hybrid

It seems still a single main power Grid cable into the CU which I assume must be standard into the meter, all isolations as already installed etc. The meter seems to have Imp & Exp written on it : EML M22. ECA2.v v1

I just cannot see how anything extra would be physically required on the grid side.

Could I just disconnect the old inverter & replace with a hybrid & connect the batteries.

Thanks I/A

All sounds about right, you should notify your DNO of the changes I believe. The batteries will have positive, negative and comms to the inverter. It may be worthwhile looking at getting an extra panel with kit so you can get the battery / inverter / panel VAT free.

 

[bignose2]

Hi,

Do you know for sure'ish that I can just take out the standard inverter & connect up the Hybrid version with most likely all the same connectors. Just extra for the battery & comms?

99% sure I don't need to notify the DNO as the connection the the grid will we identical ao before, the battery won't make any difference. I was thinking about adding an AC connected inverter (Solis RAI) & pretty sure that does need notification.

The installers did say THEY were able to get zero VAT just on the extras as can be considered as part of the original install but not sure how being joe public if can still be done but I have 2 identical installs & one is for my business anyway.

 

[johnb2713]

Hi,

Do you know for sure'ish that I can just take out the standard inverter & connect up the Hybrid version with most likely all the same connectors. Just extra for the battery & comms?

I dont see why not, I assume you have some form of CT or Generation meter and the new inverter will be a hybrid version of the existing one.

99% sure I don't need to notify the DNO as the connection the the grid will we identical ao before, the battery won't make any difference.

I'm fairly sure you do a) youre changing the inverter and therefore need their consent and b) you're adding a battery which may / may not add a significant load at times and also feed in to the grid a significant amount etc. I'm sure one of the others with far greater knowledge than me will confirm one way or the other later.

I was thinking about adding an AC connected inverter (Solis RAI) & pretty sure that does need notification.

AC coupled battery I think you mean, thats a good way to do it from the point of view of increasing you inverter power and making placement easier.

The installers did say THEY were able to get zero VAT just on the extras as can be considered as part of the original install but not sure how being joe public if can still be done but I have 2 identical installs & one is for my business anyway.

I think they're on thin ice with that one, but as you have a business you can maybe get the VAT back that way.

 

[binky]

I'm fairly sure you do a) youre changing the inverter and therefore need their consent and b) you're adding a battery which may / may not add a significant load at times and also feed in to the grid a significant amount etc. I'm sure one of the others with far greater knowledge than me will confirm one way or the other later.

it's changing the lading of the network so needs notifying for you could be sending all power from the solar array and discharging the battery at full tilt back into the grid. . Be careful with hybrid inverter settings as the cable maybe as small as 2.5mm to the CU - 25 Amps max, although I would ot run it at more than 20Amps in these circumstances.

AC coupled battery I think you mean, thats a good way to do it from the point of view of increasing you inverter power and making placement easier.

and doesn;t interefere with current installation ergo keeps any warranties.

I think they're on thin ice with that one, but as you have a business you can maybe get the VAT back that way.

Can't get VAT back unless you are VAT registered. If your business is VAT registered, could buy the panels through your business. Although 20 panels for an ice cream van might be stretching that a bit...

 

[shaunuk]

you can also just add a battery only inverter, like the Growatt spa-3000, its cheep and will just work by charging with excess solar that would have been exported, also provides redundency (your solar inverter and battery inverter won't break at the same time), downside, another app to check. upside, you may have more capacity as the solar inverter will be producing when the suns out, and if a large load is requested, both inverter will work together to minimise grid import.

 

[bignose2]

Hi,

I had started out with the thought of the Solis RAI, AC Coupled Battery install which I think is the same as the Growatt spa-3000 & then leaned towards the hybrid option, although taking out a perfectly good non-hybrid inverter I think the install would be more complicated & additional 240v wiring & notification.

I know some keep saying that it is changing the loading to the grid, solar & battery combined so would need to notify anyway even with the Hybrid, I am not too sure why. I am no expert, hence asking questions here but the one thing I was always lead to believe as long as correctly spec'd inverter don't need to worry about overloading the grid or the extra DNO G99 notification for the over 3.68kw
As long as the Hybrid inverter is limited to 3.6kw I assume works the same way my current one does, i.e. with built in limiter. My PV is 4.4kw but that is fine & actually recommended for best solar capture because it can never send more than the 3.68kw.
If this was the case I would think every single hybrid install with batteries would need the g99 application.
Now I fully understand if you add an AC battery & extra inverter there must be some mechanism to prevent both discharging as this is a separate load into the CU.

 

[johnb2713]

Hi,
I had started out with the thought of the Solis RAI, AC Coupled Battery install which I think is the same as the Growatt spa-3000 & then leaned towards the hybrid option, although taking out a perfectly good non-hybrid inverter I think the install would be more complicated & additional 240v wiring & notification.

You have the notification to do anyway, I wouldnt have thought you would need to change the 240v wiring, 3.6kW removed, 3.6 kW Hybrid installed, the load on the cable should be the same. The Solis 3.6 kW hybrid spec says max charge and discharge is 3kW to batteries son cabling should be OK.

I know some keep saying that it is changing the loading to the grid, solar & battery combined so would need to notify anyway even with the Hybrid, I am not too sure why.

I hear you and I'm of the same opinion the regulations are crazy, I can fit a 10kW shower and dont need to notify the DNO but a 3.6KW inverter I do even if I'm not exporting.

I am no expert, hence asking questions here but the one thing I was always lead to believe as long as correctly spec'd inverter don't need to worry about overloading the grid or the extra DNO G99 notification for the over 3.68kw.

But how do you know the grid capacity where you are? how do you know you wouldnt be overloading it?

As long as the Hybrid inverter is limited to 3.6kw I assume works the same way my current one does, i.e. with built in limiter.

It should be the same setup.

My PV is 4.4kw but that is fine & actually recommended for best solar capture because it can never send more than the 3.68kw.

Not quite sure what you mean here.

If this was the case I would think every single hybrid install with batteries would need the g99 application.

G98 application and yes, they do need the application.

Now I fully understand if you add an AC battery & extra inverter there must be some mechanism to prevent both discharging as this is a separate load into the CU.

No problem with this, they can both work at the same time, my two inverters (6kW Growatt and a 5kW Victron) operate together all of the time.