Fuel consumption comparison between Diesel, Petrol and Petrol Hybrid are straight forward, PHEV not quite so straight forward at present I charge up off peak 5 pence @ kWh, in March my off peak increase to 18 pence @ kWh, both distort when adding my electric and fuel cost together, my average using these figures over the past 30 month approximately 136.8 mpg.
In reality using the current average energy price 34 pence @ kWh and fuel cost a real world figures;
Ford Kuga PHEV 11.1 pence @ mile
Outlander PHEV 13.2 pence @ mile
RAV4 PHEV 9 pence @ mile
Unfortunately I have suffered a brain injury and occasionally I get confused and often say the wrong thing.