A team led by iCRAG, the SFI Research Centre for Applied Geosciences, has just returned from a marine voyage off the east coast of Ireland, conducting research aimed at informing the future development of offshore wind farms as part of Ireland’s renewable energy transition.
The researchers mapped an area of 650 km2 in the north Irish Sea. Their findings will help characterise the suitability of the area for wind turbine foundations and identify engineering challenges, including the presence of shallow gas.
Using shipwrecks as laboratories
A key focus for the research team was the study of shipwreck sites off the east coast of Ireland (Dublin/Wicklow). These sites have been the focus of ongoing research by iCRAG and project partners at Ulster University and act as natural laboratories on the seabed, allowing researchers to learn more about the structural stability of objects placed on the seabed.
The research voyage took place as part of the GIST Survey: Geohazard Investigation in the Irish Sea using Seismic and Seabed Mapping Techniques. The GIST Survey is led by postdoctoral student Dr. Mark Coughlan from UCD, who is a member of the iCRAG team.
Commenting today (13.11.19), Dr. Coughlan said: “Offshore wind will be critical to Ireland’s future in terms of reducing dependency on fossil fuels for electricity generation. Countries like Germany, the UK and Denmark have strongly pushed for offshore wind and seen significant cost reductions, and now the Irish Government is beginning to follow suit.
“However, there remain technical challenges in deploying turbines on the seabed, as seen in recent years at projects in the UK, with real fiscal implications. The more we know about the seabed and its properties, the earlier challenges can be addressed, leading to a sustainable and cost-effective marine renewable energy development plan. The data gathered during our voyage will significantly de-risk the future deployment of offshore infrastructure, including wind turbines.”
Jan Majcher, a PhD student at Ulster University studying the shipwrecks, added: “Thousands of shipwrecks rest on the Irish seabed, and they are interesting from many perspectives. They are mostly regarded as time capsules, providing fascinating insights into the past for archaeologists and thrilling underwater experiences for divers. Others contain hazardous substances, which may eventually lead to pollution of the marine environment.
“Although often considered as impediments to offshore engineering, shipwrecks are actually excellent analogies for what happens when man-made structures are intentionally placed on the seabed. Wrecks perturb near-seabed currents, causing certain types of sediments to be washed away, or scoured. Scour holes developed in this way, near shipwrecks, can ultimately lead to their collapse. The same principles apply to engineering structures on the seabed, for example wind or tidal turbines.”
During the GIST survey, researchers collected exceptionally high-quality sonar data which will allow them to monitor changes in seabed dynamics on the shipwreck sites and inform future offshore developments. Such data are also key to the effective management of wreck sites, a non-renewable cultural resource on our continental shelf.
The GIST Survey research has been funded by the Science Foundation of Ireland and Geological Survey Ireland, with support from the Marine Institute, funded under the Marine Research Programme 2014-2020 by the Irish Government. The research findings contribute to projects underway at iCRAG, the Irish Centre for Research in Applied Geosciences.