These calculations are most often used when designing lighting in the place where we work, i.e. in offices, in production halls, warehouses, as well as in parking lots or illuminating passageways. In the case of lighting in an apartment, nobody practices it, but it is worth knowing what these units mean and what they are used for.
The term lumens in short (lm) was created with the emergence of LED technology. It is a unit of measure that is used to measure the luminous flux of a given light source, while watt (W) tells about the amount of power consumed by a given light source. Lumens alone are not sufficient to determine the light output. To do this, divide the number of lumens by the number of watts. This is how we measure the efficiency of the bulb. The higher the score, the more efficient the light.
Does the same amount of lumens in different sources mean lighting with the same power?
Well, no, the same amount of lumens in different sources does not necessarily mean that it will illuminate the room with the same degree and with the same power. It depends on many factors such as the type of bulb, and more precisely the technology in which it was made, the size of the room, the height at which the light point is located, etc. Ordinary incandescent bulbs are the least effective, because they consume the most energy, and their use will be the most cost.
How to determine the real amount of light falling on a given area?
This is what luxes are used for, which define the illumination caused by an evenly distributed luminous flux of 1 lumen (lm) falling on a surface of 1 m, so 1 lx = 1 lm / m. Nobody measures it that accurately on a daily basis. We usually define it visually, i.e. whether the light is too strong, too weak or just right. This is because, in order to calculate it, it is necessary to know many parameters, including:
– the height at which the light source is located,
– light scattering angle,
– size of the illuminated room,
– how many lumens reach the area.
The color of the walls also influences it, as colors reflect light differently. What lamps should be used to illuminate the room well?
If the centrally placed ceiling lamp does not meet our expectations as to the intensity of the light it generates, you can always illuminate the room with wall lamps, floor lamps or desk / office lamps, depending on the purpose of the room. The use of many different points of light also gives us the opportunity to change the intensity of light depending on the needs. If there is too much light, we can turn off some lighting or turn it on when there is not enough of it.
