Caseres is a small municipality of barely 250 inhabitants located in the Terra Alta region of Tarragona (Spain), beside the Matarraña River, a tributary of the Ebro renowned for its high ecological value and excellent state of conservation.

Agriculture and livestock farming continue to play a fundamental role in the life of the municipality and have historically shaped its relationship with the land. In this context, the landscape and natural surroundings form an essential part of the local identity and of the way residents understand and experience the environment around them.

A TERRITORY WITH MAXIMUM LIGHTING PROTECTION

This close connection with the territory makes public lighting a particularly sensitive issue. Beyond ensuring safety and visibility in urban spaces, street lighting has a direct impact on the quality of the night sky, biodiversity and the integration of light within the landscape, aspects that are especially relevant in a natural environment of this kind.

In addition, the lighting regulations established by the Generalitat de Catalunya divide the municipality into different lighting protection zones (E1, E2 and E3), according to the environmental sensitivity of each zone. The area closest to the Matarraña River is classified as E1, the highest level of protection, due to the need to preserve wildlife, flora and the natural conditions of the night sky. The rest of the municipality is divided between E2 and E3 zones, with progressively less restrictive requirements.

TOWARDS A NEW LIGHTING MODEL

With the aim of modernising the existing installation and improving energy efficiency, Caseres Town Council launched a comprehensive renovation of the municipality’s outdoor lighting system.

The old luminaires, based on mercury vapour technology, presented limitations both in lighting quality and energy consumption, making it necessary to implement a solution adapted to current regulations and new environmental requirements.

The project needed to meet the strict lighting protection criteria of the surrounding environment while at the same time providing more efficient, comfortable and landscape-integrated lighting. The challenge was to combine energy efficiency, lighting quality and reduced environmental impact in an especially sensitive setting.

A PROJECT DRIVEN BY THE LOCAL COMMUNITY

Beyond regulatory compliance, the Town Council decided to open the process to local residents. Information meetings and pilot lighting tests were organised in different areas of the municipality to explain the available options and their impact on the environment.

These trials allowed residents to directly experience the benefits of amber lighting, particularly in terms of restoring visibility of the night sky, integrating light into the landscape and respecting circadian rhythms. Public response was overwhelmingly positive and ultimately helped build consensus around a warmer, more efficient and environmentally respectful lighting model.

As a result of this participatory process, the municipality opted for an amber lighting solution throughout the urban centre and surrounding areas. In total, 300 Clamod luminaires by Carandini were installed, a classic-style solution specifically designed to integrate into historic and rural environments such as Caseres. Their design preserves the visual coherence of the urban space while incorporating highly efficient LED technology and optical distributions designed to minimise light pollution and intrusive light.

EFFICIENCY, COMFORT AND ENVIRONMENTAL RESPECT

To maximise energy savings, the project not only included the upgrade to LED technology, but also incorporated an intelligent lighting control system that reduces luminous flux to 70% after midnight while maintaining 100% output during peak activity hours, thereby adapting to the municipality’s daily rhythm.

Thanks to this system, energy consumption has been reduced by 70%, lighting uniformity improved to values of 0.6–0.7, and a colour rendering index (CRI) of 60 achieved, resulting in greater visual comfort and more balanced lighting.

Traditionally, cooler colour temperatures have been associated with higher efficiency, while amber PC was considered a compromise between efficiency and colour quality. However, the rapid evolution of LED technology has overcome these limitations, now achieving colour rendering levels far superior to those of former mercury vapour or sodium luminaires without sacrificing high energy efficiency.

Beyond the technical data, the project has significantly improved coexistence with the natural environment, contributing to the recovery of the night sky and reinforcing the landscape identity of Caseres.