Random import every evening

RisingSun86

Fairly new to the world of solar so bear with me if I am asking something obvious. 

Recently had a 4.8kw system installed with 2 x 3.3kw batteries and an inverter, all Growatt. 

All day either I’m powered by solar or the battery is chugging along meeting all of our energy needs. Every hour when there is not enough Solar our trickle import is only around 0.01 kWh every half an hour. 

However every single evening between 8.30 and 9.30 for roughly 10 or 15 minutes, the battery doesn’t discharge enough to meet our needs and the import climbs. This means every day we import 0.4 to 0.5 kWh due to the evening spike. I know it’s not much but it’s annoying as I feel it shouldn’t be happening. 

Is there something in the battery setup that is going wrong potentially? We do have an iboost but I switched it off and it’s still doing the same thing. 

Here is the app data, any help appreciated!

ed110220

Could it be to do with using an electric oven and/or hob to make dinner? The only time we've imported any significant amounts since having the solar and batts installed last month is when using the oven and/or induction hob which exceeds the amount of power the batteries can supply. Ie there's enough in them, but it can't be put out fast enough.

ispookie666

Do you have induction hob by any chance? 

RisingSun86

Nope we have gas hobs. Pretty sure it’s not down to usage as there is no notable increase in load consumption. It’s happening right now as I type this but we’re not using anything out of the ordinary. 

It’s like the battery or inverter runs some sort of procedure the same time every night.  

Magnitio

RisingSun86 said:

Nope we have gas hobs. Pretty sure it’s not down to usage as there is no notable increase in load consumption. It’s happening right now as I type this but we’re not using anything out of the ordinary. 

It’s like the battery or inverter runs some sort of procedure the same time every night.  

There's a similar discussion here:

https://diysolarforum.com/threads/growatt-sph-and-power-import-control-from-grid.39897/

It does seem odd behaviour.