Dilip Kuner
A RESERVOIR in the Spanish region of Extremadura is the site of Spain’s first grid-connected FLOATING photovoltaic solar power plant.
Guillermo Fernández Vara, President of the Junta (Regional Government) of Extremadura, and Renewable energy group ACCIONA’s President José Manuel Entrecanales today officially opened the plant on the Sierra Brava reservoir.
The demonstration facility consists of 3,000 photovoltaic modules of different types, distributed across five floating structures with different layouts, orientation and inclination.
The aim is to analyse their performance and find out the installation and maintenance costs of the different solutions.
The plant is off the southern shore of the reservoir in the municipality of Zorita (Cáceres) and covers 12,000m2, or just 0.07% of the total surface area of the reservoir.
The environmental protection measures in the project include the installation of two floating ‘islands’ to encourage birds to nest and the provision of nesting boxes for the lesser kestrel (Falco naumanni), a protected species that lives in the area. The monitoring programme will examine the interaction between the birds and the fish stock in the reservoir with the plant and the support measures.
ACCIONA’s new floating plant has been designed to test a range of solar panels, inclinations and floating systems in a combined manner and in a real environment.
Among the most novel elements are the double-sided panels, modules with a transparent rear surface to allow sunlight to act on the reverse side, and the totally vertical layout with an inclination of 90 degrees.
ACCIONA has also developed a pioneering hybrid solution combining wind and photovoltaic energy. It consists in covering a wind turbine tower with flexible panels to produce energy for the internal electricity consumption of the turbine. The system has been installed in one of the turbines in the wind farm at Breña (Albacete).
The field of floating photovoltaic plants is taking off as the technological development associated with it underlines its technical and economic viability, particularly in regions with low availability of land or strong competition from agricultural uses.
Floating photovoltaic has shown other advantages over its land-based equivalent, for example, higher performance at lower ambient temperature and on flat sites with high solar exposure and fewer shadows, plus ease of installation; these factors can often offset the higher initial capital expenditure involved.
As for environmental benefits, floating photovoltaic reduces water evaporation in reservoirs and improves water quality as a result of lower algae growth.
Floating photovoltaic is clearly compatible with conventional large-scale hydropower. Making use of the surface of reservoirs to generate additional energy is a clear optimization of resources, both in terms of making good use of space and using existing connections to the power grid, as well as stabilizing production based on alternative generation sources.
