Cost for solar system battery

[davieogrutha]

We had a salesman by this afternoon looking at our 3.5kw solar system that has been running for 9 years now. I was in the mind of putting a battery into the system which the salesman said was possible. He said I would need 2 x2.4kw batteries and a control unit thing(can't mind the technical term for it).
It would cost £5200 to get it installed and they would have a 10 year guarantee which would include the original panels and inverter.
It's more than I was expecting, is that price too much? Or about right?

 

[renewablejohn]

We had a salesman by this afternoon looking at our 3.5kw solar system that has been running for 9 years now. I was in the mind of putting a battery into the system which the salesman said was possible. He said I would need 2 x2.4kw batteries and a control unit thing(can't mind the technical term for it).
It would cost £5200 to get it installed and they would have a 10 year guarantee which would include the original panels and inverter.
It's more than I was expecting, is that price too much? Or about right?

Expensive when you think you could buy a second hand Nissan Leaf for less than that.

 

[steveR]

@davieogrutha bearing in mind your latitude and that you only have a modest array, are batteries actually worth having? Seems a lot of dosh, unless you are off-grid?

A spot of future proofing maybe to make sure the system can also take power from a small turbine in the future....

I guess in the summer months, you have literally, (almost) around the clock power being generated, but what is your usage over a day?

 

[Doing it for the kids]

I’d never do a deal with a. Door to door salesman.

Their costs must be higher than someone you seek out to help?

 

[kill]

I was quoted 5kw lithium batteries at £1600 a few months ago and told that you can add on more whenever you require. But that’s linked to a solar system but can also be recharged from our wind turbine as well.
An interesting fact to me was they only weigh around 55kgs so could be man handled reasonably easy into an older building if required. But availability isn’t alway great atm as most things else.

 

[jackrussell101]

How much battery storage would you need for 2 houses overnight if they ran off solar during the day and the surplus was saved for nightfall?

 

[bobk]

Can you draw off a charging battery ?

 

[milkloss]

What would be the max draw from these batteries would be my concern.

 

[Kidds]

Can you draw off a charging battery ?

Yes.
Wouldn't be much use if you couldn't.

 

[Cjm]

I’ve been quoted £3500-3900 for various makes between 5.2 and 5.8kw plus £200 install as part of a new solar installation from an online company that I didn’t go with. I’ve actually gone with a 5kw battery from the electrician who’s doing the whole job. £2750 for the battery alone

 

[Poorbuthappy]

Sorry to muscle in on op, but if you install a battery on a domestic set up like this, does it automatically mean you can use the power in a power cut? Or does that still require specific set up?

 

[Exfarmer]

How much battery storage would you need for 2 houses overnight if they ran off solar during the day and the surplus was saved for nightfall?

Impossible to say without far more info
How big is your solar.
What is your night time demand?
Are you wanting to do this in summer or winter?

 

[milkloss]

It would seem the average discharge rate for a domestic battery set up is 3kw……. Perhaps don’t go boiling the fast boil kettle whilst doing the vat returns!

 

[MrNoo]

Sorry to muscle in on op, but if you install a battery on a domestic set up like this, does it automatically mean you can use the power in a power cut? Or does that still require specific set up?

If it’s grid connected no. Think you need to have a manual switch to isolate your supply from the mains or you could electrocute some poor linesman trying to fix an issue.
I think some of the hybrid inverters can automatically do this, can’t remember what the function’s called.
Been looking into inverters as have banged up 10kw of panels

 

[Cjm]

If it’s grid connected no. Think you need to have a manual switch to isolate your supply from the mains or you could electrocute some poor linesman trying to fix an issue.
I think some of the hybrid inverters can automatically do this, can’t remember what the function’s called.
Been looking into inverters as have banged up 10kw of panels

It’s called “islanding”. And yes, some hybrid inverters can do it automatically on dedicated circuits

 

[farmerm]

If it’s grid connected no. Think you need to have a manual switch to isolate your supply from the mains or you could electrocute some poor linesman trying to fix an issue.
I think some of the hybrid inverters can automatically do this, can’t remember what the function’s called.
Been looking into inverters as have banged up 10kw of panels

Thats a thought... what happens when you have solar and there is a power cut? My understanding is what the panels generate reduce what you draw through the meter and when production is exceeding consumption the excess feeds back to the grid even if you don't have an export meter. Networks can disconnect lines from the grid supply but what protects linesmen from end user generation coming the other way be it from solar, wind or grid connected batteries?

 

[steveR]

Thats a thought... what happens when you have solar and there is a power cut? My understanding is what the panels generate reduce what you draw through the meter and when production is exceeding consumption the excess feeds back to the grid even if you don't have an export meter. Networks can disconnect lines from the grid supply but what protects linesmen from end user generation coming the other way be it from solar, wind or grid connected batteries?

Well with, my setup, if you have a power cut, the feed from the Panels to teh House is cut to prevent this very problem.

 

[Exfarmer]

The law is strict, for obvious reasons , that Islanding is only allowed on non grid connections. For certain there will be some amateurs attempting it. I strongly suspect that any domestic pv or turbine staying connected to the grid in the event of a cut would swiftly burn itself out.

 

[Doing it for the kids]

If it’s grid connected no. Think you need to have a manual switch to isolate your supply from the mains or you could electrocute some poor linesman trying to fix an issue.
I think some of the hybrid inverters can automatically do this, can’t remember what the function’s called.
Been looking into inverters as have banged up 10kw of panels

how are those freebies working out for you then?!

 

[MrNoo]

how are those freebies working out for you then?!

Got 10kw put up last weekend, so just researching inverters and instal option etc etc, bit of a minefield!