If you can do 3.5 miles per kWh and charge at 10p/kWh, and drive all of those 8000 miles on that electricity – that will cost you £228.57/year in fuel. That’s not using the ICE at all, and charging only at night on your lower rate, no motorway charging etc.
The current UK unleaded price is 147.9p/l. 8000 miles at 44mpg (very achievable for most hybrids and what I was getting from my Corolla) would cost £1222.50.
So just under £1000/ year. So if you are paying £2000 extra for the PHEV version you save £1000 over the 3 year lease.
But then you have to factor in: 1. Some PHEV vehicles cost more than £2000 over the FHEV/MHEV equivalent; 2. It’s completely unrealistic they you are going to run your PHEV on electric only for the three years – in fact you are going to HAVE to use the ICE every 30-60 days just to stop the fuel going bad in the tank – which leads to; 3. You are certainly let going to have additional fuel costs of both unleaded and, likely, motorway charging or emergency home charging on higher rates, and 4. As many have noted on these boards, your overall electric bill is likely to increase quite a bit on an EV tariff unless you drink all your hot drinks/watch all your tv etc at night.
So that £1000 saving is going to evaporate once you factor in additional fuel/charging costs, and higher electric bills in general. And that is the BEST CASE SCENARIO. A great number of people who rent (and even a number who own) can’t arrange to charge at home, so the whole thing is moot. And finally, we have to accept that charging is more inconvenient and time consuming in a number of situations.
My point is: with the APs as they are now, there is no advantage to getting a PHEV at all.