If the Skoda PHEV is anything like our Tucson, to answer your question you will be relying on finding someone who manually works out the true mpg equivalent by adding the charging costs to the petrol costs and dividing the total cost by the miles. The fuel computer in our Tucson overstates mpg massively as it assumes that all miles driven on electric are free! The computer usually stages between 75 and 100 mpg but when you work it out accurately it’s the equivalent of 40mpg, which is some difference. It’s actually worse than our previous 2.0i petrol BMW X1 4WD auto (although that was a surprisingly economical car).