Recently, ocean renewable energies have been considered an attractive choice for power generation into subsea Oil & Gas upstream assets. Renewable power generation nearby offshore asset offers potential benefits in terms of improving production performance, cost saving, and greenhouse gases emissions reduction. Photovoltaics and mini-wind, thanks to their high maturity, are currently the most used to provide green electrical power to offshore platforms, which are often equipped with diesel generators and storage systems. More recently, wave renewable energy converters have reached an interesting technical level of maturity, so that they can be deployed and utilized in the field. It is anticipated that, for applications with low power requirements, wave energy converters would enable a wide variety of remote, real-time, and unmanned future solutions that can facilitate more effective monitoring and control of overall performance and safety and integration into remote asset management. This paper describes the ongoing multiyear sea test trial of a wave energy converter deployed in a gas field in the Adriatic Sea to advance Eni's Clean Sea technology for marine environmental monitoring and offshore asset inspection using autonomous underwater vehicles. The wave energy converter, a point-absorber technology, consists of a float and a spar. The float moves up and down the spar in response to the waves. As a result of this motion, electricity is generated inside the spar and stored there, in an energy storage system. The electrical energy can then be transmitted to a subsea mock-up on the seabed using a submarine electrical cable in order to demonstrate power generation, subsea battery charging, and the buoy operation capabilities.
Eni is currently involved in the R&D MaREnergy program, aiming to develop, deploy, and demonstrate suitability of wave energy renewable technologies in Oil & Gas operations. Ocean Power Technologies' (OPT) wave energy converter (WEC) is used in the Adriatic Sea to advance Eni's research and development of proprietary integrated subsea technology systems to allow future applications for remotely controlled field developments powered by wave energy, environmental monitoring, and offshore asset inspection using Eni's Clean Sea autonomous underwater vehicle (AUV). Clean Sea is used for marine environmental monitoring and offshore asset inspection ("asset integrity"). The Clean Sea technology is based on the use of AUVs. However, current methods of AUV operations have two main limitations: