Efficiency of infrared heaters

Electrically-heated infrared heaters radiate up to 86% of their input as radiant energy. Nearly all the electrical energy input is converted into heat in the filament. The filament then emits its heat by infrared radiation that is directly or via a reflector impinging on the product to be heated. Some energy is lost due to conduction or convection.

For practical applications, the efficiency of the infrared heater depends on matching the emitted wavelength and the absorption spectrum of the material to be heated.

For example, the absorption spectrum for water has its peak at around 3000 nm. This means that emission from medium-wave or carbon infrared heaters are much better absorbed by water and water-based coatings than NIR or short-wave infrared radiation.

The same is true for many plastics like PVC or polyethylene. Their peak absorption is around 3500 nm. On the other hand, some metals absorb only in the short-wave range and show a strong reflectivity in the medium and far infrared. This makes a careful selection of the right infrared heater type important for energy efficiency in the heating process.

Ceramic elements operate in the temperature of 300°C to 700°C (572°F - 1292°F) producing infrared wavelengths in the 2 - 10 micron range. Most plastics and many other materials absorb infrared best in this range, which makes the ceramic heater the most efficient infrared radiant emitter on the market.