Integrating PW2 with a smarter house/car charging

Integrating PW2 with a smarter house/car charging

I have posted in the general forum but now PW II users have their own I will post here.
I have a small PWII setup and 10kWp solar. My wife runs a Chevy Volt and I drive a Golf GTE (both PHEV). I have a deposit on an M3 but since I live in the UK we've not been told whether it will arrive in this decade (if it ever will).
My goal is to minimise my energy bills.

The first info I wanted was to view my generation, battery state and demand over a reasonable period of time - so the rather limited Tesla app wasn't any help.
Luckily there is some JSON data available on the PWII gateway and with a few lines of Powershell I have created
Fronius also expose similar data so there are corresponding pages for the inverters. The jury is out on the best way to monitor use. I started using plug adapters from a company called CurrentCost but I think they disappeared so I am trying Vera (z-wave) but finding their boxes very unreliable.

I have been controlling the charge rate on the Volt via the ODB port but this method seems to have caused quite a few premature failures of the attached charger (3 so far).

Zappi looks promising but, as yet, they have no published API

The reason for this post is to see if anyone else is having any success playing in this area/has any pointers to interesting hardware/has any examples of similar work.