So from my research, the calculation is:
P11D (ie value) x CO2 emission bracket (Aka BIK band) = BIK value
BIK value x tax bracket = payment amount
So eg, for an electric car with a P11D of 50K on a 20% tax payer wage:
50,000 x 0.02 (as electric car) x 0.2 = £200 per year
So £17 pcm. Surely it can't be that cheap?! I must be being stupid?