28th February 2013
One of the most comprehensive surveys ever carried out into the environmental impact of tidal powered turbines on marine wildlife has begun off the island of Eday in Orkney.
The environmental monitoring and measuring survey is a key part of the Energy Technologies Institute’s (ETI) ReDAPT (Reliable Data Acquisition Platform for Tidal) project.
A team from the European Marine Energy Centre (EMEC) has deployed a bespoke environmental monitoring pod, which has started to collect data to assess the potential effects tidal turbines may have on wildlife, such as mammals, at its tidal test site at the Fall of Warness off the northern island of Eday.
The key aim of the ETI commissioned and funded survey is to boost public, industry and regulatory confidence of tidal turbine technology deployment.
The innovative pod features a variety of specialist monitoring and measuring equipment brought together for the first time, aimed at capturing physical and environmental interactions with tidal turbines. These include underwater microphones (known as hydrophones) and an active sonar system (produced by Ultra Electronics), as well as more standard equipment that measures the temperature, speed and density of the tidal flow.
The pod builds on a comprehensive environmental monitoring system already developed by EMEC, which uses marine radar, video cameras, drifting acoustics and ROV surveys, as well as independent wildlife observations of the site.
The environmental monitoring project also involves Plymouth Marine Laboratory (PML) who is testing a wide range of marine coating systems to discover how well they prevent the growth of unwanted marine life such as barnacles and weeds, known as biofouling. PML is also measuring how well different coatings resist scour and abrasion. The results of this will help to inform and subsequently reduce maintenance and help devices become more energy and cost efficient.
Stewart Swatton, Marine Project Manager at the ETI said:“Robust environmental monitoring will be critical to the commercialism of marine renewable energy technologies. The more we learn about the potential impact on marine wildlife as a result of tidal turbine technology deployment, the greater the confidence we can develop in the technology to address environmental concerns and the more we are likely to be able to help stimulate the tidal industry.”
Jennifer Norris, research director at EMEC added: “This project brings together a range of cutting edge and more standard technologies which, for the first time, have been configured together to provide an uninterrupted data set so that a comprehensive study can be undertaken into the behaviour of wildlife in the vicinity of an active tidal energy device, looking for any evidence of any noticeable effects. The EMEC tidal test site is subject to peak spring tides of up to 4metres per second – highly aggressive tidal flows which are renowned as being difficult to work in - so there have been various challenges to overcome in the design, build and operation of the pod. EMEC is in a unique position having close links with technology developers, government, regulators and academia, and is a key independent site for marine renewables research projects. It is vital that full use is made of the test sites and as much data as possible are gathered around these prototype deployments prior to commercial roll-out of the technology.”
The environmental survey work is part of a wider project that supports the development of a 1MW tidal turbine, which was first deployed on 24 January by Alstom. The other ReDAPT consortium members working on the project are GL Garrad Hassan, the University of Edinburgh, EDF Energy, and E.ON.