Had the inverter and two batteries installed at the weekend so still playing with the settings.
1 how do I stop the vehicle charging from my batteries? But also charge the batteries at the off peak rate or can I only do one or the other?
2 why in the evening do my batteries feed into the grid? Surely I want to keep the batteries power overnight for my phantom load?
Thank you for your help
Loobeburt if it’s a third party charger you can’t stop the batteries discharging to your eV unless you have the charger wired in such a way the battery inverter doesn’t see the charger. Other option is simply to charge the batteries at the same time as the car. Unless you have a poor SEG export rate, currently it’s more economical to charge at night and export as much solar as possible.
Thank you for your reply. I will try and keep testing.
You don’t say which provider you are with or what inverters and battery size or car and car charger you have.
Ideally you probably want to be with Octopus on their Intelligent Octopus GO tariff or similar and be on their fixed export 15p rate once you have your export MPAN. You’ll get 6 hours of cheap 7p a unit on this tariff between 23:30 and 05:30. Other similar tariffs available from other suppliers (some slightly better, some slightly worse!)
There are other Octopus tariffs that are more complicated with variable half hourly pricing or various dips in price but this will likely require a third party control system and a bit of computer knowledge. But if you have an EV and batteries IOG will likely work out far cheaper because hopefully you’ll only be using the 7p overnight electricity all the time ~ overnight car charging and from the cheap stored electricity in your batteries in the day.
Basically the strategy is to charge the car only from cheap power overnight (23:30-05:30) and also fill your batteries to 100% at the same time to later power the house for the rest of the day. And export all solar power for 15p a unit during the day. Also in summer or if you have any extra left you can do a “timed export” to grid to finish by 23:29 and get 15p a unit for it as well. You’ll need to work out when to start this export and adjust the start time to later in the day as solar decreases throughout the year! Always keep the end time at 23:29 though, And repeat every day. Same all year round actually.
Once all this is in place, to do what you want to achieve you need to set it like this;
1) Set your car to charge between 23:30 and 05:30.
ie in the OCTOPUS APP. Set the “ready by time” to 05:30. It’ll get charged on and off automatically by octopus to reach your target by 05:30 (assuming you have a compatible car OR car charger).
2) Set your GivEnergy batteries “timed charge” from 23:30 to 05:30 and set to 100%
3) make sure eco is ON. (Sometimes other actions may turn it off) but basically it should always remain ON.
Thats it simply put. There are some occasional added complications though, for example;
A) if you get earlier cheap slots from Octopus you’ll need to stop the batteries discharging into the car, but to do this you can simply hit the charge battery “quick play” button on the GE APP. Or if you don’t want to do that you can alternatively, just set the car to charge a bit less that night and the extra earlier slots will usually just disappear. These extra slots are very rare for us and usually only occur if we need to add more than 42kW into the car - but it can happen. To avoid this plug in every night to keep the car topped up to 80% or whatever is recommended.
B) Until you’re getting paid for export you probably don’t want to be exporting too much for free. So maybe consider charging the batteries to a lower percentage overnight and let the solar fill them to 100% (less likely to happen this time of year though).
Hope that helps. Good luck.