Once, a light bulb’s consumption value in watts was related to a particular brightness. Nowadays, with the myriad types of lighting (halogen, energy-saving lamp, LED), the wattage is only related to the consumption value. In order to define a lamp’s lighting performance, two aspects are compared – brightness in lumen and light colour in Kelvin.
Brightness is measured in lumen. Lumen is a measurement of emittance, describing the light a lamp emits. In the graphic, you can ascertain which luminosity is comparable to the wattage of a conventional light bulb.
A light’s colour is decisive for the ambience and well-being a light creates. This is measured in Kelvin. Warmer light colours for a cosy atmosphere have 2,000 to 3,000 Kelvin. Offices are usually illuminated with neutral light colours with 3,300 to 5,500 Kelvin. Daylight-white lamps are found in factories or salesrooms. The higher the Kelvin, the colder the light effect. Awareness of these differences can be useful when planning your lighting, structuring rooms or creating attractive accents by playing with light colours.