Cariboni illuminated an area of Montevecchia and Valle del Curone Regional Park to evaluate the applicability of scientific research about the effects of light colour temperature on ecosystems and road safety

The artificial lighting at night must respect the biological rhythms of flora and fauna by preserving the night dark while respecting human needs. Approximately 30% of vertebrates and 60% of invertebrates are active at night: artificial light at night disturbs amphibians, birds, mammals, insects and other animals and alters their movements, food balances and mating frequency. However, most nocturnal animals are particularly sensitive to the blue component of light and, therefore, cold lighting causes greater problems of disorientation, attraction and altered predator-prey relationships.

On the other hand, plants use light both as a source of energy in photosynthesis processes and to detect information about their environment (e.g., time of day and season of the year) and change themselves accordingly. In many cases, artificial light in the night environment is bright enough to induce a negative physiological response in plants (prolonged growth periods, early or late leaf fall, leaf shape, …). Night lighting, especially with large emissions in the blue and red region, can therefore prolong photosynthesis during the night and alter growth processes, generating a marked stress situation in the plant. The preservation of biodiversity and the well-being of people pose challenges to the design of light in outdoor spaces. Taking care of biodiversity and well-being means creating a safe and comfortable environment not only for human beings but for all living beings.

Intending to assessing the concrete applicability of scientific research results concerning the effects of light colour temperature on ecosystems and road safety, we have illuminated a small area of the Montevecchia and Valle del Curone Regional Park. The portion of the park concerned is part of the municipality of Osnago (close to Lecco, Italy), where Cariboni Group is located. The Park, with 1099 catalogued species, is an important cradle of biodiversity in south-eastern Brianza, with green and wooded areas and a great variety of wildlife. The results of the test have been presented last December during the ‘Eco-Centric Lighting’ event organised in collaboration with the Osnago Municipality and held in their Sala Pertini. Discussions with the municipal administration of the municipality of Osnago and the president of the park revealed the need to replace five lighting points. The area of intervention consists of a cycle-pedestrian path and a two-way vehicular road, mainly used for walking, sporting activities (cycling, running, horse riding, …) and as a connecting route between Osnago and neighbouring municipalities. Pedestrians and sportsmen populate the area mainly during the daytime hours and in the early hours after sunset. The vehicular traffic is never heavy and is mainly concentrated during the times of travel to and from work, regardless of the season, from 07:00 to 09:00 in the morning and from 17:00 to 21:00.

Cariboni developed a dynamic white LED optical system that allows the adjustment of the light colour temperature from 2200K to 4000K. The use of a timer made it possible to have a cold light only at times when traffic is heaviest. During the rest of the night, the light is warm and has a low quantity of blue, to preserve the biodiversity of the local ecosystem and to improve visibility in foggy weather. The Switchable White technology, which can be applied to Cariboni lighting solutions for streets, spaces and urban pathways, has resulted in an annual energy saving of 77% compared to the existing lighting (made with 150W high-pressure sodium lamps). A slightly lower saving than that achievable with cool white lighting (-81%), but significantly higher than the one with amber monochrome lighting (-45%). Also, significant has been the 43% annual reduction in the blue component [%∑R (λ<500nm)] present in the light used.

Starting from the results of the test conducted in Osnago, Cariboni has developed three different technological solutions for lighting outdoor spaces protecting biodiversity and human well-being:

1. Dark Friendly Light: the right light where and when it is needed. The Dark Friendly optical systems, available in 2200K, 3000K and 4000K, prevent unwanted emissions.
2. Blue Free Light: an amber light that protects the natural ecosystem by minimising the blue content for the illumination of spaces and paths with a relevant ecological interest.
3. Switchable White Light: 1800K – 3000K. An ideal technology for illuminating hybrid spaces and routes, areas of natural interest also travelled by vehicles.

Cariboni Group

Images: ©Giulia Dentamaro