The OBREC is a novel technology of Overtopping Wave Energy Converter embedded into a traditional coastal and harbour structure defences.
In the last twenty years, a large part of the scientific community has been involved in the development of new technologies able to exploit the energy from the ocean. Only recently a new idea has been presented with the aim to reduce the cost of the device and also increasing their feasibility. This innovation consists of the integration of a Wave Converter into new or existing coastal structure. The main purposes of these “hybrid maritime structures” still remain the coastal/harbour protection from the wave motion, with the relevant added-value from the electricity production. The latest full-scale WEC device integrated into an existing maritime structure has been installed in 2016 at the Naples Harbour in Italy. The system is called OBREC (Overtopping BReakwater for Energy Conversion) and represents the first hybrid breakwater coupled with an Overtopping device that exploits the wave overtopping in order to capture part of the wave energy and convert into electricity. OBREC installation is not much more costly than building traditional breakwaters. It is built as a robust concrete structure with the turbine shaft and the gates controlling the water flow as virtually the only moving part in the mechanical system and the structure is safe even with malfunctioning of these moving parts. Other potential advantage may be the recirculation of water inside the harbour and the minimal environmental impact of the operating system.
OBREC R&D and the pilot at Naples port are part of the National Operational Programme for "Research and Competitiveness" 2007-2013 (NOP for R&C) founded project PON04a3_00303. Total budget: € 685'000.00
Evidence of success
The OBREC prototype installed at the Naples port represents the world’s first WEC prototype completely embedded into a breakwater. The ongoing monitoring campaing is providing technical date without scale effect and interesting results in terms of environmental impacts, structural resilience, hydraulic performances and low cost of electricity production have been achieved.
Potential for learning or transfer
Compared to other European countries facing the ocean, the wave energy prospective in the Italian seas is relatively low, as expected. However, the high production performance of OBREC in a mild wave climate represents a strong incentive to export the technology algo the European Atlantic coastline. This would mean also a new auspicious approach in maintenance and rehabilitation of exiting and deteriorated coastal structures.
The Carbon Footprint to build wave energy converters integrated in breakwater systems has been estimated as a proxy of the “environmental investment” needed to generate renewable electricity and the Carbon Intensity of Electricity (0.037 t CO2eq /MWh) demonstrates profitability and the opportunity to foster innovation in the field of blue energy. Considering the impact for implementing an operational OBREC module and the electricity production (12.6 MWh/yr for an OBREC single module 5 m long) avoided emissions would compensate those provided within 60 year.