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Energy Requirements

  1. Oct 22, 2008 #1
    Hi ALL,

    I have been reading up on high frequency Induction Heating & some of the benefits for particular applications.

    I was wondering if the total energy input is less than other heat sources.


    Just say we have an ordinary electric stove element that delivers x amount of heat at say 500w input power, now will a high frequency induction heater deliver more heat via the hot induced metal at the same 500w input power?

    Or will they draw the same amount of power for the same overall output?

    Thank You
  2. jcsd
  3. Oct 22, 2008 #2


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    Gold Member

    Depends on what you are asking. Energy is ALWAYS ultimately converted into heat when it is used (remember that heat is "waste energy"); so in that sense even a 500W light bulb would "generate" as much heat as a 500W induction heater; i.e. both both the bulb and the heater would raise the temperature of the room where they were used by the same amount.

    That said, another factor is how well "focused" the heat is; i.e. the induction heater might be more "efficient" than a normal stove in the sense that it delivers heat to where you want it (i.e. to heat the food in the saucepan), a normal stove will presumably radiate slightly more energy into the room.
    Hence, an induction heater would presumably use less energy (power X time) than an ordinary stove in order to heat a given amount of food to a temperature T; although I suspect the difference is pretty small.
  4. Oct 22, 2008 #3
    Yes, I think your explanation of Focused Heat hit the nail on the head & answered all the questions i had regarding this subject.
    Very good explanation.

    Thank you for that.

    PS, i'll have to pick my game up a bit so everything i ask has at least more than one straight forward answer to keep a thread going hahaha!
  5. Oct 22, 2008 #4
    have to bear in mind that conversion to RF is typically 60%. An 850 Watts microwave oven will draw 1400 Watts from the mains.
  6. Oct 22, 2008 #5
    i think a heat pump may be the most efficient(can't explain why, i hated thermo), but the real question is does it meet your specifications?
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