Actually - just seeing the ironing one (do all in one go - which is wrong btw :) ) has got me thinking
Get a real idea about how much it costs to run appliances by understanding this;
Find the power rating for your appliance. For example - my kettle (looks now) is 3000W or 3 kilo watts - i looked underneath the base plate.
If electricity costs, say 25p per kilowatt hour. Then running the kettle for say 5 minutes, 12 times a day would equal a total time on of 1 hour.
So we can say...
Power transferred in kilowatt hours) = power rating of unit (in kilowatt hours) x time (in hours)
so for our kettle
power transferred in kilowatt hours = 3 kilowatts x 1 hour = 3 kilowatt hours.
Now the cost of electricity is about 25p per kilowatt hour, so it would cost 25p per day to use the kettle.
Take a pc
its power rating is 0.25 kilowatts and its on for 5 hours. That would cost;
0.25 kilowatts x 5 hours x 25p = 31.25p or about 31p.
So in the iron example, the cost of electricity used is the amount of power it would take multiplied by how long its on for in total.
The kettle is slightly complicated by the fact that the more full it is the longer it will take to heat up to 100 deg c. So it does make sense to only heat what you need.
But essentially, the big hitters in terms of lecky usage are; washing machines, dishwashers, tumble driers. They take a lot of power because they have a heating element and they are on for about an hour per use.