A Tucson should be able to drive at least 225 miles pure electric for £18. That’s assuming a below average range per recharge (i assumed around 27 miles per charge, is in reality noticeably more), and no special tariff, just the national average price per kwh. Leaves you with around 27mpg in terms of petrol. Doesn’t really add up, does it.
The Tucson will do 38 -42 electric miles however, unlikely at high motorway speeds.
As a rough estimate 6 charges @21p kWh based on adding the full 13.8kWh.
0.21 x 13.8 x6 = £17.34
@35 miles per charge around 210 miles of all electric