Hi Lilacben,
No matter what type of heater you use the cost is based on what your supplier charges. I.E. have a look at your last bill, it will tell you what your supplier charges per unit. A unit is 1kw per hour.
E.G. if your charge is 10p per unit then the cost of a 1kw heater would be 10p per hour - 2kw heater would be 20p per hour - a 3kw heater would be 30p per hour and so on.This is exactly the same for all your electrical appliances.
Have a look at the label on each appliance and it will tell you the wattage, you can then work out what the cost is per hour.
Regards



