Cable protection in The Canary Islands

Red Eléctrica, Spain’s Transmission System Operator, needed a nature-inclusive cable protection solution for the subsea interconnector between Fuerteventura and Lanzarote. ECOncrete’s technology was chosen as a solution to both mitigate the impact of power cable laying and to restore the natural rocky reef habitat. Cable trenching can damage reefs and disrupt marine habitats. However, nature-inclusive designs for cable protection can give impacted marine habitats a second chance to rebuild.

To tackle the challenge of securing the trench on a rocky seabed, ECOncrete developed a trench protection unit designed to stabilize the high-voltage cable and restore reef habitats within a Natura 2000 marine protected area. The solution creates diverse habitats and environmental conditions that promote the settlement and growth of marine life, increase species diversity, reduce invasive species, and enhance overall biodiversity; all while meeting the project’s operational and engineering needs. Two years after installation, Red Eléctrica and ECOncrete have demonstrated the solution’s success in protecting the cable from damage while simultaneously restoring rocky reef habitats and marine ​biodiversity.

2022 - ongoing

Project dates

Between Lanzarote and Fuerteventura Islands, Spain

Location

Red Eléctrica, ECOncrete, Prysmian

Project lead and partners

Habitat creation, algae, sponges, crustaceans, mollusks, sea urchins and fish species

Target species

  • Scour and cable protection

To provide a nature-inclusive alternative to standard cable protection methods, ECOncrete’s bio-enhancing concrete technology was chosen to design a trench protection system that protects and stabilizes the cable while closely mimicking natural reefs, aiming to restore lost habitats and promote marine biodiversity. ECOncrete designed custom-fitted trench blocks based on their marine mattress design to fit the trench dimensions. The resulting nature-inclusive trench protection solution incorporates ECOncrete’s proven and patented technology, including a bio-enhancing concrete admixture, surface complexity, and a nature-inclusive design optimized to create marine habitats. 

 

One year post-installation, ECOncrete and Red Eléctrica initiated a monitoring study, conducted by local marine biologists, to assess biological growth on the trench protection units and the nearby reef. In this study, the ECOncrete units have been compared with the nearby natural reef located 10 meters away from the ECOncrete structures to document species composition, measure biodiversity, and compare colonization patterns.

 

Preliminary monitoring results of the ECOncrete trench protection units indicate that they promote algal colonization, serve as attractants for diverse benthic species and small fish; demonstrate analogy with adjacent natural reef habitats; and show high biodiversity value compared to adjacent reef environments.

Monitoring results reveal that the solutions promote algal growth and create optimal conditions for recolonization by diverse marine organisms, such as sponges, crustaceans, mollusks, sea urchins, and fish, demonstrating a clear ecological uplift compared to standard systems. The wide range of ecological niches occupied by different organisms indicates a healthy and stable ecosystem with high biodiversity which is associated with greater resilience to environmental disturbances and changes in the environment.

 

Marine life is thriving along the route, and the cable protection has blended seamlessly with the natural habitat, becoming nearly invisible in many areas, thus evidencing the ability of this solution to integrate cohesively into marine ecosystems.

  • Tailor solutions to fit surrounding ecosystems: In a specific rocky seabed area, there was no alternative but to open a trench using the specialized “rock trenching” method, which necessitates a structural solution to shield the cable from external damage and prevent interruptions to the power supply on both islands. Traditional measures such as the use of concrete, bags, or rocks are typically employed, but these have a significant impact on the local ecosystem. Considering the need to preserve the remarkable wealth of marine biodiversity present in the surrounding Marine Protected Area Natura 2000 between Lanzarote and Fuerteventura, bio-enhancing concrete technology was proposed to build the cable protection infrastructure.
  • Leverage expertise through collaboration: Designing effective NID solutions demands input from diverse experts. For this project, the solution was developed through a dynamic and collaborative process, leveraging Red Eléctrica’s experience in the design, installation, and protection of subsea cables, Tecnoambiente’s experience in monitoring and evaluating project environmental impact on the marine environment, and ECOncrete’s proven technology and expertise in the development of innovative eco-engineering solutions and Sisgen expertise in the cable laying and cable protection installation works.
  • Align with corporate sustainability frameworks: This is essential for advancing net positive biodiversity goals, and ensuring project success. For instance, ECOncrete’s solutions align with Red Eléctrica’s commitment to sustainability by minimizing environmental impact, promoting biodiversity recovery, and justifying a higher initial investment through long-term ecological benefits.

Before and After: ECOncrete Trench Block solution

How can nature inclusive cable protection restore marine diversity?

Watch how ECOncrete’s trench protection units integrate with the marine environment, attracting diverse marine life and offering an ecological improvement over traditional subsea cable protection methods. See the remarkable results 10 months after installation, as algae, sponges, and marine species thrive on the nature-inclusive structures. 

Subsea Grids Supporting Marine Biodiversity

Nature Inclusive Design Webinar

ECOncrete’s Head of Biology, Yaeli Rosenberg, Ph.D., joined a webinar hosted by Renewable Grid Initiative (RGI) and the Offshore Coalition for Energy and Nature (OCEaN). Watch her presentation alongside Roberto Cabria García from Red Eléctrica, as they discuss ECOncrete’s nature-inclusive subsea cable protection solutions used in Spain. 

Partners

Products used on this project

ECOncrete structure in sea

ECOncrete trench protection

ECOncrete

ECOncrete® Trench Protection is a customized solution designed to shield subsea cables from external damage, ensuring uninterrupted power supply. Inspired by the nature-inclusive design of ECOncrete® Marine Mattresses, this eco-engineered solution provides trench coverage and cable protection and stabilization while enhancing marine biodiversity and contributing to the restoration of local natural reef habitats.

Scour and cable protection
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