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How do electric resistance heaters convert electricity into heat?

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heating In a thermoelectric generating system a heat source—usually fueled by coal, oil, or gas—is used within a boiler to convert water to high-pressure steam. The steam expands and turns the blades of a turbine, which turns the armature of a generator, producing electric power. A condenser converts any remaining steam to water, and a pump returns the water to the boiler.

Electric resistance heaters convert electricity into heat through a process known as Joule heating. This occurs when an electric current passes through a material with electrical resistance, such as metal-alloy wire, carbon compounds, or conductive ceramics.12

As the current flows through these resistors, the material resists the flow of electrons, causing the electrical energy to be dissipated as heat energy. The amount of heat produced per second is determined by the formula:23

$P = I^{2} R$

In this equation, P represents the power (heat) in watts, I is the current in amperes, and R is the resistance in ohms. Essentially, the heater acts as a load in an electric circuit, where the work done by the power source to move charge through the resistance is released as thermal energy. These heating elements may be exposed, encased in protective metal, or integrated into printed circuits to safely transfer heat to the surrounding environment.2451