I've got a setup here in Woking - yes the sun shines here !

Ive got a 5A invertor with 2 2600 batteries. Just ordered 3 more batteries.
I had a question which was around the varied deals that Octopus has.
As I understand it they have a low cost night tariff but I don't have an electric car but is it worth it when it comes to charging batteries?
Neil.