OES-Environmental distributes metadata forms (questionnaires) to solicit information from developers involved in environmental monitoring around marine renewable energy project sites around the world. This page provides project descriptions, baseline assessment, post-installation monitoring, and links to available data and reports. Content is updated on an annual basis.

EMEC Scapa Flow Non Grid-Connected Wave Test Site

Project Site OES-Environmental

Title: EMEC Scapa Flow Non Grid-Connected Wave Test Site
Start Date:
September 01, 2011
Technology Type:
Info Updated:
July 01, 2019
EMEC Scapa Flow Non Grid-Connected Wave Test Support Buoy
Project Status: 
Test site operational
Project Scale: 
Scale test site for non-grid connected prototype devices
Installed Capacity: 
Non-grid connected test site. A purpose-built Test Support Buoy moored on site acts as a power sink to allow load-dumping of any electricity generated as heat dissipated to air. A simulated grid can be made available to support device performance analysis

In addition to the grid connected wave test site at Billia Croo, EMEC also have a wave test site that is not connected to the grid aimed at providing less challenging conditions for scale prototypes and marine operations.  The site provides a more flexible seaspace acting as a stepping stone between the test tank and real sea conditions. The site is located in Scapa Flow, to the south of Kirkwall, and was chosen for its relatively benign waters which reach almost 0.35m significant wave height. The area is 0.4km across and approximately 0.9km in length situated in water depths of 21-25m with a predominant westerly wave regime.


At the site EMEC offers developers the use of a bespoke test support buoy. If required, the device under test will be connected to the test support buoy via two umbilical cables: one for power transmission and the other for control and communications. The buoy can relay data by wireless technology allowing developers to monitor performance remotely, as well as dissipating electricity generated by the device. The buoy is also equipped to supply the marine energy devices on test with power and act as navigational aids.


Each test site comprises one berth with pre-laid foundation and attachment points, and an adjacent test area. The pre-laid foundations comprise 5m x 5m x 2m gravity-base frames loaded with densecrete blocks for equipment moorings. The area of seabed is also available for rehearsal or deployment of other tools and techniques.

Export Cables:

As the site is not grid connected, no export cable is present.


Vessel Spread:

Vessel type



Workboat (multicat)

Used to install anchors and test support buoy

Exact vessel used unknown


The EMEC Scapa Flow scale wave test site is situated in the natural harbour of Scapa Flow south of Kirkwall in the Orkney Islands, Scotland. The testing area within the site range from 21-25m water depth.

Project Timeline: 

Site selection surveys and environmental studies were carried out in 2009-10. Construction of the EMEC Scapa Flow scale wave test site was completed in 2011 and EMEC welcomed their first client on site in 2012. The EMEC wave test site at Scapa Flow is expected to continue to be operational so long as there is a need for testing in the benign real-sea regime the site enjoys. The following is a list of EMEC clients:


Licensing Information: 

EMEC holds an overarching site licences, simplifying the consent process within an agreed envelope of activity, including:

·        Marine Licence issued by the Regulator, Marine Scotland; and

·        Harbour Works Licence issued by Orkney Islands Council (OIC).

A marine licence is required for installation of marine energy converter devices at the scale test site.


A developer wishing to deploy a device at the test site must provide an outline of the proposed project. Developers are requested to provide a Project-specific Environmental Monitoring Programme and Project-specific Navigational Risk Assessment (addendum to site-wide NRA). These documents must also identify any potential device-specific environmental or navigational risks, as well as any proposed mitigation measures or risk controls. EMEC is also required to give OIC at least 21 days’ notice of each new developer wishing to install at its scale sites.

Key Environmental Issues: 

Although some seals have been recorded in the area of the site, SNH have commented that this area is not a site of concern for seals. There have been sporadic sightings of cetaceans within the observation area, in particular Harbour Porpoise and Risso’s Dolphin. Scapa Flow is selected as a proposed Special Protection Area (pSPA) for its important wintering grounds used for feeding, moulting and roosting by non-breeding shag and waterfowl. The key non-breeding qualifying Annex I species of the Scapa Flow pSPA include: Great northern diver, black-throated diver, Slavonian grebe, common eider, long-tailed duck, Common goldeneye, Red-breasted merganser, and European shag.  The Red-throated diver is proposed as a qualifying species in the breeding season only. In winter, the Great Northern Diver and Slavonian Grebe are present in Scapa Flow in internationally important concentrations. In relation to these species at the sensitive periods, the key issues to be addressed within developers’ environmental monitoring plans are:

  • Displacement due to noise (during installation, maintenance, operation and decommissioning of device)(particularly vessel noise)
  • Displacement due to physical presence of device
  • Physical harm caused by collision
  • Physical harm caused by entanglement in device moorings
  • Physical harm caused by noise


Environmental Webpage: http://www.emec.org.uk/facilities/scale-test-sites/


A revision to the Scapa Flow Environmental Description was published in January 2019 and can be accessed here: http://www.emec.org.uk/?wpfb_dl=146.


Mitigation Measures:  Where appropriate developers are required to implement their own mitigation measures should activities overlap with sensitive times of the year for marine wildlife.

EMEC Scapa Flow Non Grid-Connected Wave Test Site is located in United Kingdom.

Baseline Assessment: EMEC Scapa Flow Non Grid-Connected Wave Test Site

General Description:

The following field surveys were undertaken (or commissioned) by EMEC to inform baseline characterisation.

ReceptorStudy Description Design and Methods Results Status
  • Physical Environment

Initial site selection: Bathymetry commissioned by EMEC to Netsurvey Ltd.

Geophysical survey.

Water depths ranged from 15 to 30m across the site approximately 1 m deeper than charted depths.

  • Benthos

Initial site selection: determining biota and sediment particle size.

Grab sampling.

ROV surveys. 

Moderately low energy site. “Sheltered Muddy Gravels” and “Subtidal Mixed Sediments”.


The infaunal community was composed largely of deposit feeding species (mainly polychaetes and bivalve molluscs), with only a few crustaceans present. Two common species were Lumbrineris gracilis and Thyasira flexuosa which made up approximately 10 - 20% of individuals at all stations.


Aquatera conducted surveys to the west of St Mary’s on the eastern side of Scapa Flow, and reported results that are mostly consistent with the surveys conducted by Moore (2009).  The observed habitat resembled the biotope “Loose-lying mats of Phyllophora crispa on infralittoral muddy sediment” (SS.SMp.KSwSS.Pcri), which is not currently list as an Annex I habitat (on the UK Biodiversity Action Plan or on the Scottish Biodiversity List) and no benthic species of conservation importance were identified at the test site during surveying.

  • Marine Mammals

Baseline Acoustic Characterisation.

Seabed-mounted hydrophone deployments.

Background noise levels were in line with that which could be expected for this type of shallow water site. Contributions over and above these conditions were then identified, with the major contribution being the natural sounds from wind/waves and precipitation. The major anthropogenic source was shipping noise from distant static and mobile sources. Local shipping traffic also contributed to the sound field, although this was only present for around 7% of the time. Other sounds identified included a thunderstorm, aircraft and various biological sources.

Reports and Papers

Post-Installation Monitoring: EMEC Scapa Flow Non Grid-Connected Wave Test Site

General Description:

The following measures were outlined in the Environmental Description.

ReceptorMonitoring Program Description Design and Methods Results Status
  • Benthos

Benthic grab analysis.

Survey samples sieved and analyzed regarding species and  abundance.

Study undertaken to assist in setting up the scale site, no further work deemed necessary unless additional or different types of infrastructure are propose.

  • Birds
  • Marine Mammals

Wildlife observations.

Observations of birds and mammals by EMEC wildlife observers.

Raw data is publically available from the link below, however no report has been published.

  • Other

Biofouling studies through 3D video survey/mapping 

Characterisation of biofouling present of pre-laid foundations.

3D model of foundation and associated report.

Reports and Papers
  • The EU MaRINET2 project is working towards its vision of unlocking the energy potential of our oceans by ensuring the integration and enhancement of leading European research infrastructures specialising in research, development and testing of Offshore Renewable Energy (ORE) systems. EMEC’s test sites, including Shapinsay Sound scale site, form part of the infrastructure network available to developers with offshore renewable energy projects heading towards commercialisation.
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