Off-grid with Utilitly backup question

[Steve Fractals]

Hi all,

I'm getting up to speed with my knowledge on off-grid systems but am confused with one aspect and wonder if anyone can clear this up for me.

When you have your AC-in connected to either a generator or grid on the off-grid all in one invertor and solar and batteries have some but not enough power for the load then can these off-grid units use say 60% from the AC-in and 40% from solar generation?


I understand they can use say 60% from Solar and the 40% from the batteries but having asked one manufacturer regarding a percentage from AC-In and percentage from either Solar PV or Battery I was told No and that unit can only use 100% utiltiy/grid or a mix of solar/batt but not a mix of utility/PV & battery. This seems a bit mad to me and clearly that particular unit as an all or nothing transfer switch but do units like say growatt or others have the facility to use a percentage of the load from utility/grid from AC-In whilst using the rest from PV/Batts or are they all like this?

 

[Nobodybusiness]

Hi all,

I'm getting up to speed with my knowledge on off-grid systems but am confused with one aspect and wonder if anyone can clear this up for me.

When you have your AC-in connected to either a generator or grid on the off-grid all in one invertor and solar and batteries have some but not enough power for the load then can these off-grid units use say 60% from the AC-in and 40% from solar generation?


I understand they can use say 60% from Solar and the 40% from the batteries but having asked one manufacturer regarding a percentage from AC-In and percentage from either Solar PV or Battery I was told No and that unit can only use 100% utiltiy/grid or a mix of solar/batt but not a mix of utility/PV & battery. This seems a bit mad to me and clearly that particular unit as an all or nothing transfer switch but do units like say growatt or others have the facility to use a percentage of the load from utility/grid from AC-In whilst using the rest from PV/Batts or are they all like this?

Depends on what Unit you buy but they will definitely use Grid or Generator power to make up any short falls the inverter cannot supply to loads up to a point. Depends on the manufacture and size of Inverter.

 

[Steve Fractals]

Depends on what Unit you buy but they will definitely use Grid or Generator power to make up any short falls the inverter cannot supply to loads up to a point. Depends on the manufacture and size of Inverter.

I'm looking at 3-5 kwh all in one off-grid units. The unit I asked the supplier about was a Chinese Powland (not famous brand) unit. Can you confirm any specific models that allow the combination of a percentage of utility/grid on AC-In and a percentage of PV/Batt for loads please?

 

[Nobodybusiness]

So the unit I asked the supplier about was a Chinese Powland (not famous brand) unit. Can you confirm any specific models that allow the combination of a percentage of utility/grid on AC-In and a percentage of PV/Batt for loads please?

The only ones I know for sure are Deye and Sol-Ark.

Some of the other members will have more experience with other brands.

No knowledge of Powland.

 

[wattmatters]

There are some all in one inverters with the facility to supplement solar with grid supply, while others are not capable of this and so you need to choose grid pass through mode or solar/battery mode.

You need to choose carefully if you want your inverter to have the ability to blend AC sources.

I'm looking at an inverter at present which has this capability. PIP 8048MAX (for single phase 240 V) and the load source modes are:
- Utility First
- SUB
- SBU

The SUB mode for this inverter describes this mode as:

Solar energy provides power to the loads as first priority.
If solar energy is not sufficient to power all connected loads, Utility energy will supply power to the loads at the same time.

My current PIP 4048HS clone does not have SUB mode. So I have it programmed to flip between Utility First and SBU mode.

 

[Steve Fractals]

I was looking at the powland but not now as supplier confirmed it cannot supplement with AC and can only be all AC or all PV/batt.

Do the growatts or other brands that anyone can name other than the very expensive Sol-Ark that have this supplement from AC rather than the total switch over to AC modes please. Any All in one off-grids from 3-5kwh please.

 

[Nobodybusiness]

I was looking at the powland but not now as supplier confirmed it cannot supplement with AC and can only be all AC or all PV/batt.

Do the growatts or other brands that anyone can name other than the very expensive Sol-Ark that have this supplement from AC rather than the total switch over to AC modes please. Any All in one off-grids from 3-5kwh please.

Some of the Growatts are off grid only and some have grid tie.

I think Growatts have some kind of issue with N-G bonding which makes it hard to use grid and Solar together.

There was a whole thread about it on here if you search.

Lots of people use them here. I am just not familiar enough with them to help you on that.

I’m sure some of these guys will chime in.
I just can’t remember off the top of my head who uses them..

 

[Steve Fractals]

You would think that inverter manufacturers would list AC with PV blend in their specs or general features blurb but I've done quite a bit of googling and it seems hard info to find. Is this just how it is or am I not searching with correct terminology etc?

Is there a list available with All-in-one off-grid units with this facility?

 

[RetroGizmo]

Have a look at the MPP solar inverters with the "no battery" option.

MPP Solar Inc » Inverter Selection Guide

www.mppsolar.com

They provide off-grid (no direct AC/AC coupling of the inverter and utility) AC and PV blending.

EpEver also provide this in their Hyrid inverters, but do not provide an NG bond while the inverter is in use. The MPP units do.

 

[Steve Fractals]

Have a look at the MPP solar inverters with the "no battery" option.

MPP Solar Inc » Inverter Selection Guide

www.mppsolar.com

They provide off-grid (no direct AC/AC coupling of the inverter and utility) AC and PV blending.

EpEver also provide this in their Hyrid inverters, but do not provide an NG bond while the inverter is in use. The MPP units do.

Thanks, Struggling to find a way of getting one in UK but read that MPP are just rebadged Voltronic so looking at them and another one which is also seems to be rebadged Voltronic the Axpert King II.

​

 

[Nobodybusiness]

Thanks, Struggling to find a way of getting one in UK but read that MPP are just rebadged Voltronic so looking at them and another one which is also seems to be rebadged Voltronic the Axpert King II.

​

If you are in the UK then get a Deye..

I didn’t realize you were in the UK..

 

[Steve Fractals]

Have a look at the MPP solar inverters with the "no battery" option.

MPP Solar Inc » Inverter Selection Guide

www.mppsolar.com

They provide off-grid (no direct AC/AC coupling of the inverter and utility) AC and PV blending.

EpEver also provide this in their Hyrid inverters, but do not provide an NG bond while the inverter is in use. The MPP units do.

Just wanted to say thanks again, I contacted MPP and they have confirmed that their units do have this feature, said it was standard on all their units. Just purchased the PIP6048MT from them