Hi Baz
Don't know if I know that, but what I have found is someties they put that (watts) info on the element itself. Sometimes you need to get out the magnifying glass to see it, but I have found it that way or just have my Son read it.
small print.
Just found this in the past post.
measure the resistance of the element. Now take the voltage it is run at. Usually 240, devide by the resistance(ohms) that will give you the Amps that the element will draw. Now, multiply those amps by the voltage, = Watts OR
go here and put in the number that you know.
http://www.angelfire.com/pa/baconbacon/page2.html