Light pollution is caused by excessive artificial light that illuminates areas other than intended. These effects are significant not only for people, but also for animals and plants.
One of the consequences of light pollution is that we can no longer see the night sky. Studies show that up to 99% of Europeans live under the night sky under the influence of light pollution. Light from countless light sources on Earth reflects off particles and vapor in the atmosphere, causing the sky glow—a bright atmosphere that hides the stars behind it. This is a disadvantage not only for those interested in astronomy, but also for anyone who wants to experience the natural environment as it really is.
However, in our daily lives, a stronger concern is the effect of light pollution on our sleep patterns. Researchers are particularly concerned about the white light from LED lights. White light contains more blue light, which causes the brain to produce less melatonin. Several studies have shown that light pollution caused by street and road lighting can cause sleep problems and insomnia. It can also lead to more driver fatigue and negatively affect road safety.
Animals and plants can also be affected by too much light. A number of studies have shown that insects and nocturnal animals are affected by artificial light, which in turn can affect the entire ecosystem. Other studies have shown that too much artificial light can lead to maladaptation of trees and other types of plants in winter.
In addition to these effects, light pollution should also be considered an economic problem. Extra light is a waste of money. Therefore, preventing light pollution should be of concern to everyone in the long run. Fortunately, limiting light pollution from street and road lighting is simple and affordable.
To ensure adequate lighting while keeping light pollution to a minimum, three measures must be considered: the right type of fittings in the right places, the right shielding and the right control systems.
We now have extensive knowledge of how much light needs to be installed in different locations to achieve the desired effect. Quality lights are also designed with proper protection. As older light sources are replaced, advanced control systems are often introduced to limit light levels where possible. In residential areas, light is usually reduced at night.
Fortunately, street and road lighting is not the main source of light pollution. Recent studies have come to the conclusion that the light from buildings, billboards and other facilities causes about 80% of light pollution in cities and densely populated areas. One of the main reasons for the increase in light pollution may be the so-called “Jevons paradox”. This paradox describes a commonly observed phenomenon where the availability of more energy-efficient, and therefore less expensive, solutions leads to an increase in the use of lighting that actually negates and exceeds the initial energy savings. In other words, the market responds to more efficient solutions by using more light, not by saving energy.
However, street and road lighting is moving quickly in the right direction. Regulations and standards ensure proper implementation.