Fish-as-a-Service in the north sea

Abstract

The use of the North Sea has transitioned into an intensely used industrial area, with the climate agreement as a driving force. The Paris agreement demands countries to change their main energy resources from oil, coal and gas to renewable resources such as wind. The Dutch government chose to use the space offshore for the development of wind farms. These developments require a durable collaboration between the various stakeholders in the North Sea. Tensions exist between the different stakeholders in the North Sea, and the projected developments are expected to pressure these relationships even further. The need for shared multi-use areas grows as the North Sea is used more and more intensely. This report presents a multidisciplinary design for an artificially enhanced fisheries system within an offshore wind farm (OWF). The goal of this design is to provide a nature inclusive solution to increasing pressure on the fishing industry by the growing offshore wind sector. The possible implementation of a fishing industry within OWFs was analysed. This resulted in a number of applicable solution spaces. A notable solution was the Fish-as-a-Service concept, which resolves several issues that currently hinder the development of multi-purpose OWFs. In this solution, a company would fulfil the role of managing the fisheries in OWFs without the need for wind farm clients to actively partake in the fishing industry. Five target species were selected that could be harvested from an artificial reef system within an OWF. These species were European lobster, Brown crab, Atlantic cod, European seabass and Cuttlefish. The selection of these species was made based on economic interest, ecological interest, the potential for non-intrusive fishing methods and previous successes in other studies and/or projects. These species formed the basis of further ecological and financial examinations. Based on the biological and technical criteria following from the stakeholder and biological analysis, the most suitable wind farm site where an artificially enhanced fishing area could be implemented was selected. It was concluded that the Borssele Wind Farm Zones 1 and 2 would be the most suitable sites. The bathymetry, soil conditions, seabed dynamics and metocean data were further analysed in order to create a design for the artificial reef. A range of possible reef concepts were developed, including loose rock revetment, placed block revetment, layer cakes, biohuts, block reefs, layered pipes, shipwrecks and decommissioned oil or gas platforms. These concepts were verified for their operability and whether they met the requirements for bio-enhanced fisheries. Three preliminary designs for an artificial reef system in the Borssele OWF were made based on these reef concepts and the circumstances at the site. Of these designs, the most desirable one includes block reefs, natural stones, layer cakes, decommissioned oil or gas platforms and shipwrecks in order to promote biodiversity and yield as much biomass as possible. An Ecopath with Ecosim model was designed using available literature studies. This model was used to predict the amount of biomass produced in an OWF with and without hard substrate. An immense biomass increase in the target species European lobster (2.157.265%) and Brown crab (857.281%) was predicted with the addition of hard substrate. additionally, target species Atlantic cod and cuttlefish showed an increase of 1897% and 175% respectively. Surprisingly, European seabass was predicted to decrease with 93%. The estimated biomass was included in a study in the strengths and weaknesses of the business opportunities based on the Fish-as-a-Service concept. Costs and revenues throughout the lifetime of the sustainable fishery were taken into account, resulting in a final investment advice. The PERTH method was used to account for the uncertainty of estimating the costs of such a project. A detailed cash flow analysis was carried out in order to present a clear view on the different financial scenarios. The cash flow analysis showed a final Net Present Value (NPV) at year 25 of values between 3000 and 6000 mln EUR. This shows the profitability of the proposed design, with an Internal Rate of Return after tax of 69,90%.