Battery Timed Charge Question

dazjw

We have a GivEnergy AIO with 13kWh battery and I am wondering if we did a timed charge overnight to top it up at a cheap rate how would I find out how much it would charge up over the 5 hours if we were on something like Octopus Go?  This leads to my second question in that if I set it to charge to 100% and it reaches that in 2 hours (for example), as the house would be using the battery overnight because there is charge in it, would it just keep topping up to 100% until the schedule finishes?

Hope this makes sense and apologies for the simple questions   Just trying to work out the best schedule if we go down this route, and the option in the GivEnergy app aren't extensive.

Cheers

charles_b_2

not sure about givenergy, but my solaredge charges at the inverter rating.  When it's full, it maintains charge and the house would run off the grid until charging window finishes.

MallyGirl

dazjw said:

We have a GivEnergy AIO with 13kWh battery and I am wondering if we did a timed charge overnight to top it up at a cheap rate how would I find out how much it would charge up over the 5 hours if we were on something like Octopus Go?  [it will be temperature dependent - mine roughly charges by 30% an hour but its slower if it is very cold] This leads to my second question in that if I set it to charge to 100% and it reaches that in 2 hours (for example), as the house would be using the battery overnight because there is charge in it, would it just keep topping up to 100% until the schedule finishes? [yes it would]

Hope this makes sense and apologies for the simple questions   Just trying to work out the best schedule if we go down this route, and the option in the GivEnergy app aren't extensive.

Cheers

answers in bold

Martyn1981

Like Charles, I'm Solaredge too. So just to say, that now PV generation is dropping, and I'm running more leccy (A2A units for heat), it actually makes sense to set my battery to charge for the whole 6hr cheap rate period.

It may be full after 4, or 3, or 2 hrs. But then the house is running on cheap rate for the rest of that period, and the battery only starts suppling the house when the cheap rate ends.

Effectively, I'm using the battery charge schedule, to prevent it discharging / supplying the house. Hope that makes sense.

zxzxzx

In your position I would look at Octopus Agile being controlled by Wonderwatt.

pete-20-11

I think it's 6kW at maximum charge rate, so done in two hours. 

As others have said, once it's full, you'll run from the grid until the cheap rate ends (otherwise you waste money due to the AC to DC to AC conversion losses).

You can of course set a lower charge rate to charge it a bit slower. Kinder on the kit but possibly not as efficient. 

Re Agile, another option is the predBat software - available via Home Assistant. With GivTCP to connect the inverter to Home Assistant. If you want to get into the world of automation of course! It's addictive once you start. 🤣

dazjw

Many thanks for all the responses on this, very helpful.

Regarding Agile and Wonderwatt, looks interesting but not sure about the £6 per month fee.

With home automation, I would actually love to get into this but I fear it would consume a lot of time that I just haven't got at the moment.

I looks like, from the answers, that the battery will fill easily during the cheap overnight hours so think I'll look to move to one of those tariffs.

Cheers.