Monitoring the condition of Marine Renewable Energy Devices through underwater Acoustic Emissions: Case study of a Wave Energy Converter in Falmouth Bay, UK

Jodi Walsh, Imran Bashir, Jo Garrett, P. R. Thies, Philippe Blondel, L. Johanning

Research output: Contribution to journalArticle

4 Citations (Scopus)
133 Downloads (Pure)


Maintaining the engineering health of Marine Renewable Energy Devices (MREDs) is one of the main limits to their economic viability, because of the requirement for costly marine interventions in challenging conditions. Acoustic Emission (AE) condition monitoring is routinely and successfully used for land-based devices, and this paper shows how it can be used underwater. We review the acoustic signatures expected from operation and likely failure modes of MREDs, providing a basis for a generic classification system. This is illustrated with a Wave Energy Converter tested at Falmouth Bay (UK), monitored for 2 years. Underwater noise levels have been measured between 10 Hz and 32 kHz throughout this time, covering operational and inactive periods. Broadband MRED contributions to ambient noise are generally negligible. Time-frequency analyses are used to detect acoustic signatures (60 Hz – 5 kHz) of specific operational activities, such as the active Power Take Off, and relate them to engineering and environmental conditions. These first results demonstrate the feasibility of using underwater Acoustic Emissions to monitor the health and performance of MREDs.
Original languageEnglish
Pages (from-to)205-213
Number of pages17
JournalRenewable Energy
Issue numberPart A
Early online date24 Oct 2016
Publication statusPublished - Mar 2017



  • Underwater Acoustics
  • Acoustic Emission
  • Condition monitoring
  • Health Monitoring
  • Marine Renewable Energy
  • Wave Energy Converter

ASJC Scopus subject areas

  • Renewable Energy, Sustainability and the Environment
  • Acoustics and Ultrasonics
  • Ocean Engineering

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