As we conserve energy by the use of compact fluorescents or LED (light emitting diodes), occasionally things go wrong, with these devices also radiating radio interference.
The old pear-shaped incandescent bulbs were very inefficient. However, some of their replacements do not meet emission standards and are the source of electromagnetic interference.
In the USA fluorescent lights in a Los Angeles office are causing problems for Verizon's Long-Term Evolution or LTE network.
Among the other cases being investigated by the Federal Communications Commission is one we told you of several months back, that of the lights in a Texas hair salon getting into the mobile phone network.
In Australia, complaints about TV reception have come to Australian Communications and Media Authority which has traced the problem to some LED lights.
In England and elsewhere too there have TV interference complaints, even spreading to set-top boxes and cable TV.