The solar battery draws 1.91 kW half hourly or 3.82kWh, charging the PHEV at the same time 3.71 kW or 7.42kWh.
2 x 7kW charges = 14kWh + battery 3.82 total = 17.82kWh.
If you have a 3 phase supply Octopus are quite happy to supply and fit a 22kWh EV charger.
Unfortunately I have suffered a brain injury and occasionally I get confused and often say the wrong thing.