Case study

Grid Connection Assessment for Tidal Electrical Generator


A tidal energy developer is planning to test their marine device at the European Marine Energy Centre (EMEC) in Orkney. EMEC provides facilities for developers to test their devices and provides them with a connection to the national grid. In order to connect their device, the developers need to demonstrate compliance of their design against the EMEC requirements, which are aligned with the national electrical standards.

Our solution

We carried out an independent assessment of the developers’ design involving the following studies:

  • Isolation study to ensure that the isolation of the various components of the device is complete, appropriate and safe;
  • Earthing assessment of the proposed design against BS 7430-1998. This study included an assessment of the rise of earth potential against the BS 7430-1998 requirements;
  • Access to the device complies with the Electrical Safety, Quality and Continuity (ESQC) Regulations 2002;  Protection study to assess the suitability of the switchgear protection rating and discrimination with the existing EMEC protection scheme;
  • Power Quality study aimed at assessing the following quality parameters of the exported power to the grid:
    • Voltage fluctuation in accordance with Engineering Recommendation P28,
    • Harmonic response in accordance with Engineering Recommendation G5/4;
    • Power factor response.


This project helped the developer identify gaps in their design and provided them with guidance for updating their device architecture in such a way that the device could be connected to the grid.