Well I've now spoken at length to Nick at VanBitz. Very helpful and knowledgeable. However he thinks we might just need possibly an additional panel a new MPPT controller and a lead carbon
battery rather than lithium. The other issue is time scales. Due to a cancellation they have a slot next week where they can do a panel and lead Carbon but if I want Lithium it's a much longer install and they can't do it until the end of August / September.
At first I thought well this is a backward step but maybe it's not. Presumably in the future if we do move to lithium everything they install bar the
battery is still useful? Anyway it is what it is and I can't wait until September. I certainly don't want to start ringing round other suppliers and going through it all again either.
I'm going to just have to be guided and go with whatever they can fit next Wednesday.