I currently have it running so both house battery and car charge on 12am - 5am schedule.
Now we are getting some decent sun, how can i setup the charger/invertor to follow this logic.
Always charge house battery first, if battery is charged then charge EV if connected and not fully charged and finally export if other two conditions are met.
My setup is GIV-HY3.6 Invertor, 9.5KWh battery and GIV-EV-7.2 EV charger.
Tabulous What tariff are you on ? (And are you on a FIT arrangement ?)
Always charge house battery first, if battery is charged then charge EV if connected
The only slight caution with that approach is that house battery will charge on any old dregs of solar, whereas EV needs at least 1.4kW. On a sunny nice day, it's probably academic, but maybe charge car around peak solar even if the house battery is not yet full. The house can then fill up after solar has dropped below 1.4kW.
DD Im on British Gas EV3 tariff(8p / KWh 12am - 5am). FIT is also British Gas, £0.15 / KWh
Not sure you understand my question, its how do i setup this ?
First time i tried i just ended up dumping battery to EV......
Both house battery and car are set at the moment to charge 12am - 5am. But if there is alot of solar energy, i want this to top up the car if possible.
Tabulous The question about FIT/export was whether you get paid for exporting excess solar or not.
Depending on what you get paid for exporting and what you pay on your overnight import tariff, you may well be better off exporting the excess solar rather than using it to charge your car.
BTW (I found out after the event) but If you have a FIT tariff and you have a smart meter installed then the FIT scheme requires you to go onto measured output not deemed output.
Anyway, to avoid your battery dumping your stored charge into the EV requires the CT clamps for the inverter to be placed onto the cables that go into your house fuse box and NOT on your meter tails. That way the inverter doesn’t “know” about the EV charging.
Diagramatically:
House Electricity Meter —- EV connection —- Inverter CT clamps — House fusebox
Often things are setup like this:
House Electricity Meter —- Inverter CT clamps. —— House Fusebox
`— EV connection
So the inverter “sees” the load from both the house and the EV charger
geoffreycoan CT clamp is on Live tail before the House meter.
100AMP Fuse ---- Inverter CT clamp ---- House Electricity Meter ---- House Fusebox ---- EV connection
geoffreycoan Anyway, to avoid your battery dumping your stored charge into the EV requires the CT clamps for the inverter to be placed onto the cables that go into your house fuse box and NOT on your meter tails. That way the inverter doesn’t “know” about the EV charging.
That works well for third-party chargepoints (and is how I have my zappi wired). But one might have hoped that with an integrated GE chargepoint, under inverter control, it could do slightly better ?
Sorry OP I can't help with specifics. But my tariff is similar, and I do all charging overnight and export as much solar as I can. Using solar effectively costs 15p/kWh, which is twice the overnight rate.
Tabulous Thanks, the problem with that approach as you have seen is that the inverter sees everything from the house and EV as being load that it needs to try to supply by discharging the battery.
As @DD says you would hope that the GivEnergy inverter and EV charger can talk to one another sufficiently to stop this happening, but if you can’t (or it doesn’t work as you expect) then other than having the EV charger connection and your CT clamp moved (it can be before or after the house meter, it doesn’t make much difference), the only option to achieve what you want is to stop the battery discharging when you are charging the car.
You can either:
Option 2 would probably be the best, but if the sun goes in your battery won’t support your house load unfortunately
geoffreycoan mmmm think i'll just leave it as is.
Yesterday PV gen was good, 34KWh with 25KWh Exported @ £0.15 / KWh.
So probably more cost efficient to feed in than charging car.