Christine Röckmann

What does stakeholder involvement mean for fisheries management

The Common Fisheries Policy (CFP) sets the guidelines for the management of European fisheries. The CFP is revised every 10 years, and the last two revisions have laid the groundwork for extending stakeholder participation in European Union fisheries management. The fishery industry and nongovernmental organization (NGOs) especially are recommended to be given greater influence. In this paper we report results from an international survey on fisheries stakeholders’ preferences for the three pillars of sustainable fisheries activities as defined in the CFP: ecological, economic, and social. Results of the survey show that industry member preferences were significantly different from the preferences of authorities, scientists, and NGOs. The preferences of the three latter groups did not vary significantly across stakeholder group. This raises the question of what consequences the planned stakeholder involvement in the CFP may have, given the preferences revealed in our survey.

Technical Risks of Offshore Structures

Offshore areas are rough and high energy areas. Therefore, offshore constructions are prone to high technical risks. This chapter elaborates on the technical risks of corrosion and biofouling and technical risks through mechanical force. The expected lifetime of an offshore structure is to a great extent determined by the risk of failures through such risks. Corrosion and biofouling threaten the robustness of offshore structures. Detailed and standardized rules for protection against corrosion of offshore structures are currently lacking. There is a need for an accepted uniform specification. A major technical risk of a combined wind-mussel farm is that of a drifting aquaculture construction that strikes a wind turbine foundation. We investigate two scenarios related to this risk: (1) Can a striking aquaculture construction cause a significant damage to the foundation? (2) If a drifting aquaculture construction gets stuck around a turbine foundation and thus increases its surface area, can the foundation handle the extra (drag) forces involved? A preliminary qualitative assessment of these scenarios leads to the conclusion that a drifting mussel or seaweed farm does not pose a serious technical threat to the foundation of a wind farm. Damage to the (anticorrosive) paint of the turbine foundation is possible, but this will not lead to short term structural damage. Long term corrosion and damage risks can be prevented by taking appropriate maintenance and repair actions. Contrarily to mussel or seaweed farms, the impact/threat of a drifting fish farm on structural damage to a wind foundation depends on type, size and the way of construction of the fish cages. The risk of extra drag force due to a stuck aquaculture construction relates particularly to jacket constructions because any stuck construction may lead to (strong) increase of the frontal surface area of the immersed jacket structure and thereby give increased drag forces from currents or waves. To ensure an optimal lifetime and lower operational costs maintenance aspects of materials for both offshore wind and aquaculture constructions should be taken into account already in the design phase of combined infrastructure.

Operation and Maintenance Costs of Offshore Wind Farms and Potential Multi-use Platforms in the Dutch North Sea

Aquaculture within offshore wind farms has been identified as one of the many possibilities of smart use of marine space, leading to opportunities for innovative entrepreneurship. Offshore areas potentially pose less conflict with co-users than onshore. At the same time, offshore areas and offshore constructions are prone to high technical risks through mechanical force, corrosion, and biofouling. The expected lifetime of an offshore structure is to a great extent determined by the risk of failures. This chapter elaborates on logistical challenges that the offshore industry faces. Operation and maintenance (O&M) activities typically represent a big part of the total costs (e.g. 25–30% of the total lifecycle costs for offshore wind farms). The offshore wind energy sector is considered an industry with promising features for the public and private sector. Large wind farms farther off the coast pose high expectations because of higher average wind speeds and hence greater wind energy yield (in terms of megawatts per capital). These conditions entail additional challenges in logistics, though. One of the main hurdles that hinders use of offshore wind energy is the high cost for O&M. The offshore wind industry will have to solve these problems in order to achieve substantial cost reduction - alone or jointly with other (potential) users. It is precisely the logistical problems around O&M where most likely synergy benefits of multi-use platforms (MUPs) can be achieved. The offshore wind energy industry is eagerly looking for technical innovations. Until now they mostly sought the solutions in their own circles. If the combination of offshore wind energy and offshore aquaculture proves to be feasible and profitable in practice, there may be an additional possibility to reduce the O&M costs by synergy effects of the combined operations. Logistic waiting times, for example, can result in substantial revenue losses, whereas timely spare-parts supply or sufficient repair capacity (technicians) to shorten the logistic delay times are beneficial. A recent study suggests that a cost reduction of 10% is feasible, if the offshore wind and offshore aquaculture sectors are combined in order to coordinate and share O&M together. The presented asset management control model proves useful in testing the innovative, interdisciplinary multi-use concepts, simulating return rates under different assumptions, thus making the approach more concrete and robust.