Battery Self install of battery storage

[littlespark]

I’ve been doing a fair bit of research on adding battery to my own house… there has been mention of it on other threads, but I’ll start a new one just for this.

Have been asking the “experts” in the local wholesalers, but I know they are salesmen first, and experts second.
However, saw this advert…



I’ve already got PV, with a good FIT price, so don’t want to affect that in any way.

The guy in YESSS said replace my existing inverter, and mount the battery’s next to it in the attic, but someone else has told me they are not to be in an attic for fire risk.


Can I fit the new inverter and battery’s separate to the PV? And not be limited to the <4kW?

The house heating is gas, but we can fit a few electric heaters to back that up…. Same with changing the gas hob to electric.

 

[UNG]

Worth checking with your home insurance company as the installation of PV batteries can affect your insurance

 

[littlespark]

Worth checking with your home insurance company as the installation of batterise can affect your insurance

Will that be just for inside the house, be that in an attic or garage… or on the outside?

I’ll also have to see how the No VAT offer on renewables works when I am not VAT registered myself

 

[richy3333]

First up DON'T believe anything a wholesaler advises - they are not experts but salespeople and the YESSS terms and conditions if you have a credit account are very biassed against you. They're all on bonuses to sell you rubbish.

I cant see the detail of the offer but just add a battery. We can't your existing inverter cope with it? Our experience though is that unless you are adding 10kW then anything less is not really that worthwhile. The main thing with these systems is not the materials but the companies technical assistance. We've sometimes had to spend up to 5 hours going back and forward with them to get systems up and running properly. Personally I'd stay well clear of YESSS but also go for Solis, Puredrive/Duracell or Givenergy.

Under FIT if you change the inverter you are supposed to advise your FIT provider. But I wouldn't bother.

 

[UNG]

Will that be just for inside the house, be that in an attic or garage… or on the outside?

From some things I have heard from a few sources the insurance companies are wanting the batteries in a detached shed or outbuilding

I’ll also have to see how the No VAT offer on renewables works when I am not VAT registered myself

I think you can only get the VAT back on batteries if they are installed at the same time as the panels

 

[littlespark]

First up DON'T believe anything a wholesaler advises - they are not experts but salespeople and the YESSS terms and conditions if you have a credit account are very biassed against you. They're all on bonuses to sell you rubbish.

I cant see the detail of the offer but just add a battery. We can't your existing inverter cope with it? Our experience though is that unless you are adding 10kW then anything less is not really that worthwhile. The main thing with these systems is not the materials but the companies technical assistance. We've sometimes had to spend up to 5 hours going back and forward with them to get systems up and running properly. Personally I'd stay well clear of YESSS but also go for Solis, Puredrive/Duracell or Givenergy.

Under FIT if you change the inverter you are supposed to advise your FIT provider. But I wouldn't bother.

The details of the supplied components;



For 2400 all in…. What I don’t use can be stocked for other jobs.

I’m trying to work out is there an optimum size of battery and inverter for a gas heated house, and wether changing say the gas hob to electric… or having an electric radiator to back up the heating fed from the battery, rather than using gas all the time.

 

[plugsandsparks]

How much solar do you have ?
Also that system you have looked at, is it capable of deciding from the solar output whether to charge the battery,or feed the load? It does appear to be a retro-fit solution for a PV install, so i would hope it has the controls necessary

 

[littlespark]

It’s 16 panels, less than 4kW…. And having a look at it, it’s wired as only one string.

The inverter I’ve got is older, and at the time, didn’t have any option to check it using a phone app…. I’ve got to go into the attic to see if it’s working….. so replacing it now would give me more functionality.

I assume the new inverter takes from the solar, feeds the house first, and any excess goes to battery before being sent to grid.

The meter will still read what’s being generated for FIT whether that’s direct from PV, or from the battery… so there’s no change there.


I’d also want to know if this will work in “island” mode…. Ie, giving me useful electricity from battery if there’s a powercut.

 

[plugsandsparks]

Here is a link to the "Datasheet"

https://www.tradesparky.com/solarsparky/battery-storage/sunsynk/hybrid/sunsynk-36kw-inverter-single-phase-ecco?affiliate=product_feed&utm_source=product_feed&utm_medium=product_feed&utm_campaign=product_feed&gad_source=1&gclid=Cj0KCQjw4MSzBhC8ARIsAPFOuyWNTnP7huKxenDCXOQRoxKDn4R2LAUNhiH3qDq6IsWgs4d2and0jnoaAujiEALw_wcB

Things that leap out are: Start up voltage is a little higher than other available systems, means it starts up later in the day and drops out earlier in the evening , not really a big deal but it is there.
Also your existing string voltage max is probably higher than this inverter can handle with 16 panels on one string.
To know for sure, double check you only have two DC cables connected to your existing inverter, get the product details of your existing inverter and if you can details of your existing panels and confirm No off.

Also remote monitoring appear to be an option - i.e. pay for a wifi dongle or the like

Otherwise this product appears to do what you want it to do

 

[timhoward]

The house heating is gas

Combi - or do you have hot water cylinder?
I'm just learning about Solar Power Diverters as I need to fit one soon, it appears to have two CT clamps to measure grid and PV and can dump any surplus into the immersion heater once the batteries are fully charged. Just thought I'd throw this thought out there!

 

[littlespark]

Combi - or do you have hot water cylinder?
I'm just learning about Solar Power Diverters as I need to fit one soon, it appears to have two CT clamps to measure grid and PV and can dump any surplus into the immersion heater once the batteries are fully charged. Just thought I'd throw this thought out there!

Unfortunately, I took the water cylinder out and put a combi in as our hot water pressure was less than effective… (which in turn caused a leak, but another story)

I was thinking of somehow using the surplus to preheat any water entering the combi, so less gas is used to heat up, or an electric radiator to heat a room… maybe replace the gas hob with electric?

 

[richy3333]

Our experience of fitting batteries is that anything less than 10kW is not worthwhile and really 20kW is preferable.

 

[littlespark]

Our experience of fitting batteries is that anything less than 10kW is not worthwhile and really 20kW is preferable.

But will that affect my FIT when the PV is less than 4?

And is that the inverter output, or the battery… which is kWh?

 

[richy3333]

I dont think it will affect your FIT. Dont tell them (although you are supposed to do so). You'll theoretically just be putting less back to FIT if its going into battery storage but they'll never know.

Battery, not inverter

 

[baldelectrician]

But will that affect my FIT when the PV is less than 4?

And is that the inverter output, or the battery… which is kWh?

I would keep the exiting PV as is and add a seperate battery system

If I had the spare cash I would go for a 10kW (MIN) system and a system that gives whole house backup in the event of a power cut.

Givenergy and Enphase comes to mind

The Givenergy passes the whole house through the system and will switchover in the event of a power cut.

 

[littlespark]

Thanks @baldelectrician thats why I am asking the questions.

If I forget that I have PV at the moment, and go with a grid charged battery… get an electricity tariff with lower night time and charge overnight, use during the day… it won’t matter if I get a 3, 5 or 10 kW (or whatever) inverter for the battery…. And I can locate it wherever…. I just think the attic is not a good place.

Making use of it by changing what I can to electric… hob, for example… but there’s nothing much can be done with the gas combi boiler with no tank.


Thinking of the PV now, will the battery side know when the sun is shining and let the PV take the load, or would the two invertors need to talk to each other somehow?
Likewise, will the battery’s charge off the PV (after the FIT meter) before charging from grid?

 

[baldelectrician]

With the Giveenergy the PV is wired directly to the All in One hub, this means the PV is also powered when there is a power cut (direct from the battery storage) and it also will know what you are importing and exporting.
You can also set priorities for each thing, the best option is to generate the PV (the meter on the PV system will register this) and store the energy

Just to note- DO NOT get a smart meter as they can switch you from deemed export (via solar meter) to actual export (registered from the smart meter), you will lose money with a smart meter if they decide to use actual export

 

[littlespark]

i have no desire for a smart meter just now.... Not because of the conspiracy thoughts that they can cut you off/ change your tariff/ spy on you etc.... but more because i do not think the technology is quite there yet...

I mean, i have a simple energy monitor CT around the tails, but it doesnt know the difference between grid load or PV going back.


However... if i need to change tariff or supplier to mske use of overnight cheap rate... will i be forced to take a smart meter?

 

[richy3333]

Up in the north SiS meter people told me last week that they have less than 18 months of non smart meters left. After that people won’t get a choice - it will be a smart meter or nothing.

You can have a second PV system and a battery. We did. Puredrive system with 3 PV systems and 3 inverters. 2 are on a FIT. Clamp on tails and the. Another on the chosen PV system. The other 2 are not affected.

 

[Gavin John Hyde]

Late to this one but have a look at teh givenergy All in One with 13.5kwh of storage 100% depth of discharge. it can be installed as ac coupled on its own to utilise solar/ac charigng, if you wanted then now or later you can add the gateway for full house back up. only costs £350 for the gateway seperate. the full AIO is around 4.5k depending where you shop.