All fluorescent tubes, compact fluorescent and energy saving lamps are available in different colour renditions, or burning temperatures measured in Kelvin.

Colour temperature is a standard method of describing colours for use in a range of situations and with different equipment. Colour temperatures are normally expressed in units called kelvins (K). Note that the term degrees kelvin is often used but is not technically correct.

For example an energy saving lamp with a colour temperature of 3500K burns at 3500 Kelvin this colour is known as white.

There is a high demand nowadays for daylight lamps which burn at a temperature of 6500K, these lamps are often used to combat SAD (seasonal affective disorder)