Sähkövastuslämmitys

Sähkövastuslämmitys, known in English as electric resistance heating, is a method of heating that converts electrical energy into heat through the passage of electric current through a resistive material. This process is governed by Joule's law, which states that the heat generated is proportional to the resistance of the material and the square of the current flowing through it.

The core component of any electric resistance heating system is the heating element, typically made of a material with high electrical resistance, such as nichrome (a nickel-chromium alloy) or kanthal (an iron-chromium-aluminum alloy). These materials can withstand high temperatures without oxidizing or degrading. When electricity flows through the heating element, its resistance causes it to heat up. This heat is then transferred to the surrounding environment or object through conduction, convection, or radiation.

Electric resistance heating is a versatile technology used in a wide range of applications. In residential settings, it is commonly found in electric heaters, toasters, kettles, hair dryers, and electric ovens. Industrial applications include process heating, drying, and melting. The simplicity of design and control makes electric resistance heating a reliable and often cost-effective heating solution, especially where electricity is readily available and competitively priced. However, its energy efficiency is inherently 100% in terms of converting electrical energy to heat, but the overall efficiency of heating a space depends on factors like insulation and heat loss.