The geotechnical challenges of tidal turbine projects

Andrew A. Small, Greg K. Cook, Michael J. Brown

    Research output: Chapter in Book/Report/Conference proceedingConference contribution

    3 Citations (Scopus)

    Abstract

    Tidal energy projects offer a predictable renewable energy source. Therefore several sites around the coast of the United Kingdom (UK) have been identified to have the potential to host multiple array turbine developments that could be used to generate upwards of 100MW each. However, the high tidal energy environment required to provide the input to tidal power devices present a combination of design and installation challenges to developers and engineers. Whilst the water depths are comparable to offshore oil and gas projects in the southern North Sea, tidal energy projects present significantly different seabed and associated geotechnical challenges that require novel solutions. Concerns have been expressed regarding the design of turbine base structures, which is often based upon typical nearshore/offshore soil sampling and geotechnical laboratory testing techniques that are often inappropriate for the seabed materials encountered. This issue is further compounded by the design constraints imposed on the base structure foundations (e.g. tripod gravity base structures). These include strict leveling tolerances required for efficient turbine operation, and which require a detailed understanding of seabed bathymetry at each turbine location where multiple seabed contact points may be required. In addition to the tidal energy turbines, inter-array cables that connect the turbines and export cable routes which distribute the power to shore also present their own design and installation challenges. It is often overlooked, but significant uncertainty lies in the definition of cable corridors with respect to the seabed materials. In many cases burial may be considered as a means of product protection where seabed conditions allow. This paper aims to examine the geotechnical issues associated with the difficult seabed and environmental conditions present at typical tidal turbine sites in the UK and globally in an attempt to offer some potential solutions. These issues typically include; difficulties in performing site investigation operations, coarse mobile seabed sediments, challenging seabed topography, exposed bedrock and hard substrates, derivation of appropriate geotechnical parameters, difficulties in foundation design and installation, high cyclic environmental loading, array and export cable lay, on-bottom stability and mechanical protection, amongst others.

    Original languageEnglish
    Title of host publicationASME 2014
    Subtitle of host publication33rd International Conference on Ocean, Offshore and Arctic Engineering. Proceedings
    PublisherAmerican Society of Mechanical Engineers
    Number of pages9
    Volume9A
    ISBN (Print)9780791845530
    DOIs
    Publication statusPublished - 2014
    Event33rd International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2014 - Palace Hotel, San Francisco, United States
    Duration: 8 Jun 201413 Jun 2014
    http://www.asmeconferences.org/omae2014/

    Conference

    Conference33rd International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2014
    Abbreviated titleOMAE 2014
    CountryUnited States
    CitySan Francisco
    Period8/06/1413/06/14
    Internet address

    Fingerprint

    Turbines
    Cables
    Leveling (machinery)
    Tidal power
    Bathymetry
    Point contacts
    Topography
    Coastal zones
    Gravitation
    Sediments
    Sampling
    Soils
    Engineers
    Testing
    Substrates
    Gases
    Water

    Cite this

    Small, A. A., Cook, G. K., & Brown, M. J. (2014). The geotechnical challenges of tidal turbine projects. In ASME 2014: 33rd International Conference on Ocean, Offshore and Arctic Engineering. Proceedings (Vol. 9A). [ OMAE2014-23892] American Society of Mechanical Engineers. https://doi.org/10.1115/OMAE2014-23892
    Small, Andrew A. ; Cook, Greg K. ; Brown, Michael J. / The geotechnical challenges of tidal turbine projects. ASME 2014: 33rd International Conference on Ocean, Offshore and Arctic Engineering. Proceedings. Vol. 9A American Society of Mechanical Engineers, 2014.
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    Small, AA, Cook, GK & Brown, MJ 2014, The geotechnical challenges of tidal turbine projects. in ASME 2014: 33rd International Conference on Ocean, Offshore and Arctic Engineering. Proceedings. vol. 9A, OMAE2014-23892, American Society of Mechanical Engineers, 33rd International Conference on Ocean, Offshore and Arctic Engineering, OMAE 2014, San Francisco, United States, 8/06/14. https://doi.org/10.1115/OMAE2014-23892

    The geotechnical challenges of tidal turbine projects. / Small, Andrew A.; Cook, Greg K.; Brown, Michael J.

    ASME 2014: 33rd International Conference on Ocean, Offshore and Arctic Engineering. Proceedings. Vol. 9A American Society of Mechanical Engineers, 2014. OMAE2014-23892.

    Research output: Chapter in Book/Report/Conference proceedingConference contribution

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    Small AA, Cook GK, Brown MJ. The geotechnical challenges of tidal turbine projects. In ASME 2014: 33rd International Conference on Ocean, Offshore and Arctic Engineering. Proceedings. Vol. 9A. American Society of Mechanical Engineers. 2014. OMAE2014-23892 https://doi.org/10.1115/OMAE2014-23892