cost of running oil filled radiators 2kw

Hello peeps,
I know this subject has been discussed before but that was over twelve months ago, I have a shop premises and am keen to know how much an oil filled 2kw heater would cost to run, on maximum setting, for one hours usage, all advice and help is much appreciated.

The unit of electrical supply is the Kilowatt Hour, so a 2KW heater will use 2 units per hours on max setting.
At General Purposes commercial rate of 15.25c that will cost 30.5 cents plus VAT.

Might be a bit cheaper if thermostat on heater kicks in and out when the room gets too warm but still a very expensive form of heating.

thanks Hoagy and Dipole for your replies, they were helpful.