Acciona has embarked on a pioneering project testing the use of photovoltaic (PV) panels on wind turbine towers to improve the efficiency of wind power production.

The company has installed flexible organic PV modules on a wind turbine tower at the Breña wind farm in Spain. The PV panels will produce energy for the internal electricity consumption of the turbine and will enable Acciona to test their performance as well as their application in this setting.

The PV panels will be able to cover at least partially the energy required by the wind turbine’s auxiliary systems. Acciona says that it could also investigate the possibility of including battery technology in the system – allowing the turbine’s energy needs to be met even when the sun is not shining.

Acciona has installed 120 solar panels facing southeast-southwest on the 80 m-high steel tower of a Nordex-Acciona AW77/1500 turbine. The panels are distributed at eight different heights, occupying around 50 metres of the tower's surface area. The photovoltaic modules, with an overall capacity of 9.36 kWp, are of Heliatek technology (HeliaSol 308-5986 model). They are 1 mm thick, and each one has a surface area of 5986 x 308 mm.

In contrast to the conventional technology used in the manufacture of photovoltaic models based on silicon, these organic panels use carbon as raw material and are characterized by their structural flexibility, which makes them adaptable to very different surfaces. Other key features are lower maintenance costs, less energy consumption during manufacture, easier logistics and the complete recycling of the materials used, although their efficiency is still below that of silicon modules.

“The hybridization project in Breña means the optimization of the use of space for renewable energy production and it will enable us to test the efficiency of organic photovoltaics, a technology that we believe has one of the best improvement curves in terms of technological efficiency. That is why we have decided to pilot it,” said Belén Linares, Energy Innovation Director at Acciona.