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.
As the site is not grid connected, no export cable is present.
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.
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:
- Energy Bag Device, University of Nottingham - installed 2012
- CorPower Ocean C3 Wave Energy Converter – installed January 2018
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.
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.