Light on the horizon
Lighting technology is now so advanced that ecological and economic improvements to lighting systems and reduced light pollution are quite easy to achieve.
Optimum results in terms of energy efficiency and environmental compatibility presuppose the right choice of lamp and light fitting and mode of operation.
Good lighting practice
In order to minimise the negative impacts of artificial light, various factors need to be considered in built-up areas, urban margins and the open countryside. more >>
There is much common ground between good lighting practice in the natural environment and for human life, energy management and astronomy; only the focus differs. In all cases the basic principle is to minimise the use of artificial light and make correct use of the light that is needed.
- Nature: Light with limited long-distance effects, with the lighting columns kept as low as possible, with shielded light fittings and enclosed housings, avoiding natural and near-natural habitats, and minimising the blue component of the light spectrum.
- Human beings: Light sources and luminaires that do not illuminate private homes, do not cause glare and have a low proportion of blue in the light spectrum.
- Energy: Energy-efficient, long-life light sources with a positive eco-balance, targeted lighting.
- Astronomy: Lighting with as much long-wave light as possible, fully shielded light fittings that do not radiate light into the atmosphere.
The recommendations relating to mode of operation and type of lamp and light fitting take account of the relevant codes and standards and are designed to satisfy as many of the needs of the natural environment, human life, energy management and astronomy as possible.
Light sources must satisfy the criteria of energy efficiency (high luminous efficacy), long service life and a low or zero proportion of ultraviolet and infrared light.
- LED (colour temperature warm white)
- High-pressure sodium lamp
A full eco-balance must be based on the various factors relating to manufacture, operating hours and lamp recycling.
Used light sources must be disposed of safely and in accordance with the regulations.
Light fittings must satisfy the criteria of targeted lighting so as to avoid light scatter and glare.
- Full cut-off luminaires (fully shielded light fittings)
- Reduced mounting height
- Targeted light control through correct installation and the use of suitable reflectors, flat diffusers (discharge lamps), intelligent optic design (LEDs), enclosed housings, and fittings with low surface temperatures
The mode of operation must satisfy the criteria of true need. Artificial lighting should only be employed to produce light with the intensity and during the times required.
- Avoidance of unnecessary light
- Single-lamp operation of twin-lamp luminaires or dimmed operation
- Limited periods of illumination, proximity switches
In the interest of avoiding unnecessary light, outdoor recessed uplighters, skybeamers and illuminated or luminous advertising billboards should not be used.