Is there any way of keeping my Solar & batteries working in the event of a power cut

[NugentS]

I have a 4kWp solar system with a Sunnyboy inverter on the roof facing almost directly south - this is on the house
I also have 30 or so kWh of batteries off two luxpower inverters installed in the very nearby but unattached garage each capable of about 3kW - so 6kW in total. These batteries are AC coupled. This is about a days worth of power given I have a high electricity use for a variety of reasons.
I have 16mm SWA between the house and the garage to charge and discharge the batteries
There is an EPS circuit in the garage to a twin socket for the freezer in the garage.

I recently had a powercut which essentially turns off the solar and the batteries - its a safety design that I understand why - so no issues there. I have a 100amp main fuse which popped when I was pulling about 40 amps (estimated). Apparently it was quite badly burnt and the fitting was a bit loose. Anyway all working now with new fitting

My question is how can I go about setting things up so that I have power (as delivered by solar and batteries) in the event of a powercut even if its a manual switchover.
AIUI I would need:
1. An Isolator to prevent me feeding anything back into the mains (although there exists a practical issue of fitting that to the equipment board - a lack of space, but that can be solved [somehow])
2. Something to generate the signal that the mains generates - I assume a 50Hz(?) signal so the equipment I have thinks its connected

Any ideas?

 

[binky]

I have a 4kWp solar system with a Sunnyboy inverter on the roof facing almost directly south - this is on the house
I also have 30 or so kWh of batteries off two luxpower inverters installed in the very nearby but unattached garage each capable of about 3kW - so 6kW in total. These batteries are AC coupled. This is about a days worth of power given I have a high electricity use for a variety of reasons.
I have 16mm SWA between the house and the garage to charge and discharge the batteries
There is an EPS circuit in the garage to a twin socket for the freezer in the garage.

I recently had a powercut which essentially turns off the solar and the batteries - its a safety design that I understand why - so no issues there. I have a 100amp main fuse which popped when I was pulling about 40 amps (estimated). Apparently it was quite badly burnt and the fitting was a bit loose. Anyway all working now with new fitting

My question is how can I go about setting things up so that I have power (as delivered by solar and batteries) in the event of a powercut even if its a manual switchover.
AIUI I would need:
1. An Isolator to prevent me feeding anything back into the mains (although there exists a practical issue of fitting that to the equipment board - a lack of space, but that can be solved [somehow])
2. Something to generate the signal that the mains generates - I assume a 50Hz(?) signal so the equipment I have thinks its connected

Any ideas?

If your batteries are AC coupled, they usually have an option for use as a UPS, but that involves wiring ccts directly to them, and they will only take a limited supply. So power to essential items only.

 

[NugentS]

Which is what I am doing with my in garage freezer.

I'd like a way to power the house (maybe not the oven, but the microwave should be very practical, along with lights and plugs throughout) without wiring special circuits (and having to use more cable between the house and the garage). The batteries are (assuming they have the power stored) easily capable of powering the house under normal circumstances and all without leaking to the grid

 

[binky]

Which is what I am doing with my in garage freezer.

I'd like a way to power the house (maybe not the oven, but the microwave should be very practical, along with lights and plugs throughout) without wiring special circuits (and having to use more cable between the house and the garage). The batteries are (assuming they have the power stored) easily capable of powering the house under normal circumstances and all without leaking to the grid

Not sure if it would work, but, you could fit a change over switch on the incoming mains, and outdoor socket and try using a small genie - would need to have decent pure sine wave output. I really don't know how the solar inveters would respond to a genie, but theoretically this would fool them into seeing a 'grid voltage' and allow them to generate.

 

[NugentS]

Could I do this with a UPS? I have enough of those. Plug the UPS output into the mains (ignoring the live male plug issue). The problem I can see is that at least for an brief period of time the UPS would be trying to supply the whole house whilst the batteries and solar wake up something that a small UPS (like what I have) won't do. The solar isn't so important - its the batteries that would have to be able to supply from zero or am I overthinking this.

Now most of the non lights etc is on UPS's anyhow so they would kick in and supply the computer equipment (its not whole house UPS) so I guess its just an extension of that. The UPS would need to supply lights etc - which it could probably do quite easily.

 

[binky]

I really don't know if that would work, I've never tried to do anything like that. Unless you get regular power outages, the cure might be more costly than the benefits. The genie idea was from a customer with numerous freezers, he grew a lot of his own food. Even if the batteries don't like it, at least you have the genie to power essentials.

 

[Stuboy1]

I have an isolated output on my Solis Hybrid specifically for loss of grid its a 3Kw circuit. It will also run in island mode if you delve into the software ;-)

 

[NugentS]

I have the same. But the batteries are inthe detached garage which means that I would have to run a scond circuit between the house and the garage AND then distribute this out into the house somehow.

I would much rather be able to isolate the mains (simple isolation switch) and then fool the solar panels and the batteries into thinking that the mains was attached

 

[binky]

I have an isolated output on my Solis Hybrid specifically for loss of grid its a 3Kw circuit. It will also run in island mode if you delve into the software ;-)

hadn't noticed that setting in the options (mind you I've never looked for it). Does this allow it to run as per normal rather than just powering the UPS feature socket?

 

[Stuboy1]

Island mode is just that, its an island system, i suspect if it sees 50Hz coming from somewhere else it might get VERY upset, especially if it can't sync to the phase, that would release LOTS of magic smoke! You would need to be dead sure of what your doing with the appropriate lockouts before using island in a non island setting! Looks like a lot of RTFM will be required.
Cheers
Stu

 

[binky]

Island mode is just that, its an island system, i suspect if it sees 50Hz coming from somewhere else it might get VERY upset, especially if it can't sync to the phase, that would release LOTS of magic smoke! You would need to be dead sure of what your doing with the appropriate lockouts before using island in a non island setting! Looks like a lot of RTFM will be required.
Cheers
Stu

just wanted to double check, I've never had the need to install an island system


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