Solar battery fit to existing solar.
Discussion
Are there any others that have OR are thinking of installing a battery to their existing solar?
We currently have 5.6kWh of solar/14 panels and are now seriously considering an EV so batteries and a "zappi" seem to be the next step.
Thinking of the export and Octopus int Go etc as a good option as well.
Battery wise, under 10kWh seems too small, over 15/16 too much. A neighbour has put in 16kWh of Fogstar recently with a victron inverter and decided AC coupling was their way to go.
What have you done or are considering???
We havent decided whether AC or DC coupling is best....Google Ai is fun....
We currently have 5.6kWh of solar/14 panels and are now seriously considering an EV so batteries and a "zappi" seem to be the next step.
Thinking of the export and Octopus int Go etc as a good option as well.
Battery wise, under 10kWh seems too small, over 15/16 too much. A neighbour has put in 16kWh of Fogstar recently with a victron inverter and decided AC coupling was their way to go.
What have you done or are considering???
We havent decided whether AC or DC coupling is best....Google Ai is fun....
I'm hopefully getting a 16.1kWh Fogstar fitted along with a new 6kW Inverter to my existing 4.8kWh solar.
Waiting on a G99 back from the DNO and battery delivery date.
I've also moved away from Octopus to EDF as their rates are much better (14p for Export and 7p between 11pm and 6am) making the payback quicker. I've worked out it will take me 4 years to breakeven on my usage.
Waiting on a G99 back from the DNO and battery delivery date.
I've also moved away from Octopus to EDF as their rates are much better (14p for Export and 7p between 11pm and 6am) making the payback quicker. I've worked out it will take me 4 years to breakeven on my usage.
superpp said:
I'm hopefully getting a 16.1kWh Fogstar fitted along with a new 6kW Inverter to my existing 4.8kWh solar.
Waiting on a G99 back from the DNO and battery delivery date.
I've also moved away from Octopus to EDF as their rates are much better (14p for Export and 7p between 11pm and 6am) making the payback quicker. I've worked out it will take me 4 years to breakeven on my usage.
What made you go for the bigger battery....the 16 instead of say the 10??Waiting on a G99 back from the DNO and battery delivery date.
I've also moved away from Octopus to EDF as their rates are much better (14p for Export and 7p between 11pm and 6am) making the payback quicker. I've worked out it will take me 4 years to breakeven on my usage.
Capacity requirements are dependant on each use case, how much is your annual usage?
I'm fine with 6kwh in batteries though in winter it does run out around 10pm before recharging on Octopus on their cheap night rate tariff, this summer I'm still at 80% capacity at 10pm due to the amount of sun we are receiving.
I'm fine with 6kwh in batteries though in winter it does run out around 10pm before recharging on Octopus on their cheap night rate tariff, this summer I'm still at 80% capacity at 10pm due to the amount of sun we are receiving.
I added a battery to existing solar - very easy, but needed a new inverter which was battery compatible. Trivial for a competent installer.
But, while having a battery really does help a solar installation - I really wouldn't do this "because you might get an EV" - an EV with a ~80kwh capacity isn't going to charge very long from a little 5kwh battery. I have a 32kwh battery, and never charge the EVs from the battery, only from offpeak (cheap) energy. Better (IMHO) to use the battery to cover (some of) the house demands, and get an EV tariff with cheap power.
But, while having a battery really does help a solar installation - I really wouldn't do this "because you might get an EV" - an EV with a ~80kwh capacity isn't going to charge very long from a little 5kwh battery. I have a 32kwh battery, and never charge the EVs from the battery, only from offpeak (cheap) energy. Better (IMHO) to use the battery to cover (some of) the house demands, and get an EV tariff with cheap power.
I wont be charging the EV from the batteries. as others here have said.....Its purely for the house and income from export.
Upping the G99, to maximise export.
Export the solar during the day at 12per excess going to the battery. Topping it up at night whilst charging the EV. Discharging the battery during the $$$ time 4-7pm.
Upping the G99, to maximise export.
Export the solar during the day at 12per excess going to the battery. Topping it up at night whilst charging the EV. Discharging the battery during the $$$ time 4-7pm.
Had solar only, added a Fogstar battery and Victron inverter.
Battery is therefore AC coupled and doesn t interface with the solar in anyway.
16kWh Fogstar eco, Victron Multiplus GX, data cable and Ethernet cable, 2 hours of the electricians time.
Total cost £2200
Haven t used peak rate power since it s been in, use approx 12 kWh a day from the battery, 30kWh overall.
Battery is therefore AC coupled and doesn t interface with the solar in anyway.
16kWh Fogstar eco, Victron Multiplus GX, data cable and Ethernet cable, 2 hours of the electricians time.
Total cost £2200
Haven t used peak rate power since it s been in, use approx 12 kWh a day from the battery, 30kWh overall.
JD said:
Had solar only, added a Fogstar battery and Victron inverter.
Battery is therefore AC coupled and doesn t interface with the solar in anyway.
16kWh Fogstar eco, Victron Multiplus GX, data cable and Ethernet cable, 2 hours of the electricians time.
Total cost £2200
Haven t used peak rate power since it s been in, use approx 12 kWh a day from the battery, 30kWh overall.
2 hrs, works for me. I have a guy coming for a look on friday to what I have. I mention AC v DC coupling and he said he prefers DC coupling. I havent read anything anywhere that says to change from the current fitout to DC coupling is better and easier...Battery is therefore AC coupled and doesn t interface with the solar in anyway.
16kWh Fogstar eco, Victron Multiplus GX, data cable and Ethernet cable, 2 hours of the electricians time.
Total cost £2200
Haven t used peak rate power since it s been in, use approx 12 kWh a day from the battery, 30kWh overall.
What sort of inverter do you currently have? That might dictate a good chunk of the effort/expense involved.
I wouldn't rush to get a Zappi over any other charger, they don't work very well with other manufacturers hybrid inverters and Octopus now try and get everyone on IOG onto car-based integrations that leave a Zappi essentially running as a fairly dumb charger.
I have a 16kWh battery, I wouldn't want any less, some days I'd welcome some more.
I wouldn't rush to get a Zappi over any other charger, they don't work very well with other manufacturers hybrid inverters and Octopus now try and get everyone on IOG onto car-based integrations that leave a Zappi essentially running as a fairly dumb charger.
I have a 16kWh battery, I wouldn't want any less, some days I'd welcome some more.
To add on to this, agree don’t need to get a Zappi, I’ve had two of them last one cost £600 and I basically use it as a timed charger, my next charger I’ve just ordered is costing £110!
In regards battery sizing too big or too small, you just want to buy the biggest you can exploit all of daily, at the cheapest £/kWh
If you are going Fogstar, wait until Black Friday as they do hefty discounts, 16kWh was £1200 last year.
In regards battery sizing too big or too small, you just want to buy the biggest you can exploit all of daily, at the cheapest £/kWh
If you are going Fogstar, wait until Black Friday as they do hefty discounts, 16kWh was £1200 last year.
JD said:
Had solar only, added a Fogstar battery and Victron inverter.
Battery is therefore AC coupled and doesn t interface with the solar in anyway.
16kWh Fogstar eco, Victron Multiplus GX, data cable and Ethernet cable, 2 hours of the electricians time.
Total cost £2200
Haven t used peak rate power since it s been in, use approx 12 kWh a day from the battery, 30kWh overall.
Interesting. I didnt know about AC coupling. I have a growatt Hybrid system with 10Kwh of expensive growatt batts.Battery is therefore AC coupled and doesn t interface with the solar in anyway.
16kWh Fogstar eco, Victron Multiplus GX, data cable and Ethernet cable, 2 hours of the electricians time.
Total cost £2200
Haven t used peak rate power since it s been in, use approx 12 kWh a day from the battery, 30kWh overall.
So if I added a foggy and Victron, AC coupled i'd hook it into the same RCBO, and then add a power clamp on the main house feed so it knows when to charge, and when to discharge? Currently the main solar inverter manages all this.
I guess it would not be the most elegant solution as the growatt already manages my existing batteries well.
Griffith4ever said:
So if I added a foggy and Victron, AC coupled i'd hook it into the same RCBO, and then add a power clamp on the main house feed so it knows when to charge, and when to discharge? Currently the main solar inverter manages all this.
I guess it would not be the most elegant solution as the growatt already manages my existing batteries well.
You would need to get your head around the system design, to make sure you don't end up charging one from the other.I guess it would not be the most elegant solution as the growatt already manages my existing batteries well.
Can you not just connect a cheaper battery up to the inverter you already have? I am pretty sure my battery has Growatt communication profiles already loaded
JD said:
Griffith4ever said:
So if I added a foggy and Victron, AC coupled i'd hook it into the same RCBO, and then add a power clamp on the main house feed so it knows when to charge, and when to discharge? Currently the main solar inverter manages all this.
I guess it would not be the most elegant solution as the growatt already manages my existing batteries well.
You would need to get your head around the system design, to make sure you don't end up charging one from the other.I guess it would not be the most elegant solution as the growatt already manages my existing batteries well.
Can you not just connect a cheaper battery up to the inverter you already have? I am pretty sure my battery has Growatt communication profiles already loaded
I'll deal with it at some stage - I get that I'll have to set it up so they don't conflict.
Cheers
superpp said:
I've also moved away from Octopus to EDF as their rates are much better (14p for Export and 7p between 11pm and 6am)
If you're on an EV tariff with overnight electricity costing eg 6p, can you fill up a massive battery or 3 then export it all during the daytime back to them? 
Gassing Station | Homes, Gardens and DIY | Top of Page | What's New | My Stuff