I have a 5kw inverter and a 5kw battery with no solar panels. Chinese make. Is it possible to feed back into the grid with this setup. My electricity bill increased drastically 

25 minutes ago, FransSmith said:

I have a 5kw inverter and a 5kw battery with no solar panels. Chinese make. Is it possible to feed back into the grid with this setup. My electricity bill increased drastically 

Need more info. I'm not sure how to interpret this question.

Firstly, your footer says you've got an 8kW Sunsynk inverter with 9900W of panels and 3x5kWh batteries installed. With this setup you can technically definitely export power to the grid if your installation has municipal or Eskom approval.

If you have a 5kW inverter and 5kWh battery with no solar panels, you've got no means of generating your own electricity for export. At best you could draw energy from the grid and feed it back, if that makes financial sense for you.

What do you mean by "Chinese" make? Deye and Solis are two Chinese brands making grid-tied and hybrid inverters that are capable of feeding back. If you've got any off-grid inverter, anything that's not grid-tied, then you can't export with it.

When did your bill increase after installed the  inverter or suddenly one day long after the inverter was installed ? 

What inverter is it ?

Are you using communication between inverter and lithium ?

If it's after you installed the inverter and there no communication between inverter and battery  then it's normally due to float charging the battery 24/7 and so going to cost . 

It's alway best to install solar even if it's just enough to keep the battery fully charged and not to charge or float charge from grid at all .

 

I think people tend to not realize the inverter itself is drawing power 24/7 to power itself.  So if there is no solar input this additional draw eventually comes from the grid.

E.G. in my case this is a rough estimation based on the difference between actual load and PV/Battery input/output.

That is about 3.5kw per day of additional load from just the inverter so if you can't offset that with solar input that is getting added to your bill irrespective if you can charge and discharge your battery back into the grid. 

Another assumption here will be there is no bidirectional meter installed so it might also be illegal and unsafe in that instance and if there is a bidirectional meter selling back is usually at a lower rate than buying so that will also operate at a loss if there is no solar input.

Edited February 6, 20251 yr by -cK-

My apologies, my neighbour installed it and I am asking on his behalf. I think the brand is Ecco. But his electricity bill went sky high. I told him about my Sunsynk and the Ct clamp preventing feeding back. I told him I will try and find out on this forum because I am not 100% sure as well

53 minutes ago, GreenFields said:

Need more info. I'm not sure how to interpret this question.

Firstly, your footer says you've got an 8kW Sunsynk inverter with 9900W of panels and 3x5kWh batteries installed. With this setup you can technically definitely export power to the grid if your installation has municipal or Eskom approval.

If you have a 5kW inverter and 5kWh battery with no solar panels, you've got no means of generating your own electricity for export. At best you could draw energy from the grid and feed it back, if that makes financial sense for you.

What do you mean by "Chinese" make? Deye and Solis are two Chinese brands making grid-tied and hybrid inverters that are capable of feeding back. If you've got any off-grid inverter, anything that's not grid-tied, then you can't export with it.

My apologies, my neighbour installed it and I am asking on his behalf. I think the brand is Ecco. But his electricity bill went sky high. I told him about my Sunsynk and the Ct clamp preventing feeding back. I told him I will try and find out on this forum because I am not 100% sure as well

49 minutes ago, FransSmith said:

My apologies, my neighbour installed it and I am asking on his behalf. I think the brand is Ecco. But his electricity bill went sky high. I told him about my Sunsynk and the Ct clamp preventing feeding back. I told him I will try and find out on this forum because I am not 100% sure as well

Open to correction. Okay, so as I'm understanding this, your neighbour installed an off-grid inverter with battery back-up only, ie. with no solar panels to generate any of his own power. This is good for backup to have power when you need it when Eskom goes down, but there are inherent losses that WILL give him a bigger bill at the end of the day.

It's firstly the battery and inverter's self-consumption, ie. like adding another two useful appliances onto your household that don't generate any power by themselves but keep draining constantly.

Then there's the losses of putting power into the battery from grid, and returning power back from it, especially if he's got the inverter in a mode that prioritizes draining the battery each day. You never get back all that was put in. Best would probably be some kind of UPS-mode or SUB-priority, solar then utility and then as a last option the battery.

It is unlikely that this type of inverter will be able to feed power back to the grid. Best thing is probably to add panels.

2 hours ago, FransSmith said:

My apologies, my neighbour installed it and I am asking on his behalf. I think the brand is Ecco. But his electricity bill went sky high. I told him about my Sunsynk and the Ct clamp preventing feeding back. I told him I will try and find out on this forum because I am not 100% sure as well

As already explained here, the inverter and the battery will use power just to keep themselves running. But what is "sky high"? I can see the hardware adding 5% to the bill, but that's not "sky high" by any reasonable use of the term.

Can it feed back? Maybe. My inverter (Goodwe) can feed back even if run with no panels.

Now, if you feed back and it's done properly and you want to get credited, then you need a bidirectional meter. Most domestic meters in this country are one directional. So if you have a regular meter, and the system does feed back into the grid, then the meter doesn't know that the electricity is coming from your battery, into the grid, it just senses current and acts like the power is coming from the grid. 

Then your bill could go up quite a lot. But also your batteries would be discharging. 

So where's the manual for that inverter? Get that. Check the settings. My inverter can also be run just as a UPS - it will charge the battery from grid, and only discharge when the grid goes down. So see if this inverter can run in different modes. 

You might also want to check the CT clamp, or get an electrician with some solar know how to do that. They are directional, and the system may misbehave if the CT is the wrong way around.

Get your neighbour to enrol on this forum. It will be quicker for everybody if he can ask things directly, and we can do the same.

 

4 hours ago, FransSmith said:

with no solar panels

Just that part make feeding back to the grid totally unproductive.

The ecco inverter self consumption is about 0.3 amps which is around  70w per hour  . So now depending on how the battery setting are set (% or V )will determine how much battery will be consuming . If the inverter is set on USE it will be constantly float charging the battery and so with self consumption and float charging it's going to get expensive to have that setup running 24/7.  

 

Feeding into the grid usually needs an inverter with certified grid-tie capability and permission from your utility, so most off-grid or backup-style Chinese units won’t be allowed to push power back. The bill spike might just be the inverter drawing more standby power than expected. I’d double-check its settings and logs. If you’re looking into cheaper tariffs, I found https://octopus-referral-code.co.uk handy for comparing options and switching.

Edited January 16Jan 16 by Bubblerate