DC pollution of AC mains due to modern compact fluorescent light lamps and LED lamps

Modern so-called energy efficient equipment often draw current only during a very short period of the period of a power supply mains. This is causing unwanted non-sinusoidal and harmonic currents. In some cases even a single diode is used for rectification causing direct current (DC) in the mains supply. To reduce dissipation the semiconductor components switch very fast, which is causing interference, especially in medium- and high-frequency communication systems. The pollution in the mains supply due to energy efficient LED and compact florescent lamps is shown and discussed.