I already have 15kWh of house battery but yes tempting to get more. I can export 5kW max without upgraded grid connection.
Import 6hrs x 10kW = 60kWh
@ 7p = £4.20
Export 12hrs x 5kW @ 20p = £12
12-4.20 £7.80 \ day ≈ Better than a kick in the bollocks 😄