BioFREE: An International Study of Biofouling Impacts on the Marine Renewable Energy Industry

Abstract

The success of the marine renewable energy (MRE) industry is dependent upon maximising energy capture and minimising down-time. Device performance is negatively impacted by the growth of fouling organisms, leading to reduced efficiency and reliability; anti-fouling strategies are costly and time consuming. Biofouling also reduces accuracy of data buoys and sensors used to assess the hydrodynamic resource and device performance. While biofouling has been a recognised problem for centuries, deployment of MRE devices creates several unique issues. Additional concerns exist over the role that MRE infrastructure may play as ‘stepping-stones’ promoting the spread of non-native and invasive species. A paucity of published studies exists concerning biofouling in this sector. With a general trend towards stricter environmental controls, it is essential that the MRE industry demonstrate commitments that minimise disturbance and promote positive impacts. Given small margins for MRE, there are potentially substantive benefits from tackling biofouling in terms of increased investor confidence. The BioFREE project (a collaboration between Heriot-Watt University and the European Marine Energy Centre (EMEC) in the UK) is addressing these issues by detailed characterisation of the biofouling communities from multiple habitats used by the MRE sector, and monitoring benthic impacts following deployment and decommissioning. BioFREE is developing a workable Standard Monitoring System designed to facilitate data collection using practical and effective methods. Frames are populated with settlement panels, data loggers, and components comprised of materials of greatest concern to MRE developers. Components of this system can be treated with anti-fouling coatings. Frames are being deployed in a variety of habitats at additional test centres and research institutes located in Japan, Chile, France, and the USA; organisms are recorded quarterly to identify the major foulants, determine the rate of settlement and growth, and study successional changes. These studies indicate strong species-specific seasonal settlement patterns. Fouling communities vary between deployment habitats depending on factors such as hydrodynamic conditions, water depth, and substrate type. These findings will allow recommendations for test centres and developers to minimise the impacts of fouling, chiefly through selective scheduling of deployments and maintenance, in different habitats, to times when the settlement of fouling organisms will be minimal or their removal will be least costly. In addition, BioFREE has created training materials to help inform the MRE industry of ways to better capture biofouling information when conducting operations at sea. Practical suggestions are informed by recent maintenance and decommissioning operations conducted on MRE infrastructure. These studies have identified structural areas and materials of particular concern from the impacts of biofouling. The lead role of EMEC, as a representative of MRE developers in the sector, is allowing promotion of project outputs within the industry and between test centres. These findings are being disseminated through conference presentations, technical reports, scientific publications, public engagement, and webinars planned for the near future.