I've got an 8.2 and a 5.2 battery... I was thinking of replacing the 5.2 with a larger one... but given the state of the company. It would have to be a bargain... an 8.2 or 9.5 for around 1k at the most.
I'm still sending more to the grid than I like... last year it was just over 800kwh still... whilst still importing some 1500kwh... although 80% of that is between Nov-Feb.
But given that we use in the region of 5000-5200kwh a year on the house... it's not as bad as it could be.
On a really sunny day like the last couple of weeks of April, we were generating 27kwh a day (4kw array), batteries were at 55-60% full after running through the previous evening/night. So it only takes 5-6kwh to refill them... house use takes another 8kwh or so during the day. So that's around 15kwh export some days... more when the days are longer and generation hits around 30kwh..
Given we earn just 12p/kwh now... and electric rates are going up as are standing charges... it's more important to use as much as possible than ever.