In cooperation with ScottishPower Renewables, Andritz Hydro Hammerfest installed a 1MW pre commercial tidal power turbine on December 2011 at the Falls of Warness, in the Orkney Isles UK.
Technology: The HS1000 turbine is based on the technology of a smaller turbine, the HS300, which was installed in Norway as the first ever tidal current turbine with permanent connection to the public grid in 2004. The 1 MW HS1000 device is a fully submerged, bottom mounted, rotor, variable pitch turbine. The nacelle houses the turbine, gearbox, generator and associated components. The pitch of the rotors is variable to present the most efficient angle of incidence to the oncoming flow. On reversal of the tide the rotors alter pitch so that the turbine generates maximum generation from the tidal environment, hence the nacelle does not yaw. The rotor blades turn slowly when the tide is running; the gearbox increases the rotational speed to allow for generation at network frequency. The device itself incorporates a self-levelling device allowing the rotor to face directly into the current.
Foundations: The turbine is mounted on a 22-meter-high seabed mounted substructure. Three ballast packages were used as gravity-based foundations resulting in the substructure having a dry weight of approximately 800 tonnes. It is possible to remove the nacelle from the support structure, leaving it in situ while the nacelle is taken away for maintenance.
Vessel spread: A DP vessel with a heavy lift crane was used to install the substructure, cable and nacelle. The exact vessel used has not been specified.
EMEC’s Fall of Warness tidal test site (just west of the island of Eday, lying in a narrow channel between the Westray Firth and Stronsay Firth).
|Section 36 (Electricity Act) Concent||Scottish Ministers|
|Marine License (Marine (Scotland) Act) Concent||Marine Scotland||Issued 2011|
|FEPA License||Marine Scotland||Issued 2011|
|Licence to Disturb Marine Species||Marine Scotland|
|Licence to Disturb Basking Shark||Marine Scotland|
|Town and County Planning Permission||Orkney islands Council|
- FEPA condition 2: The licensee shall ensure that all substances or articles deposited during the execution of the works are inert and do not contain toxic elements which may be harmful to the marine environment, the living resources which it supports or human health.
- FEPA condition 3: The licensee shall ensure that only the substances or articles described in Part 1 of the Schedule shall be deposited under authority of the license and that any debris or waste materials arising during the course of the works are removed from the site of the works for disposal at an approved location above the tidal level of Mean High Water Springs.
- FEPA condition 14: The licensee shall where appropriate undertake monitoring of the area pre and post installation and post decommissioning of the deposition the seabed subject to this license e.g. deployment of a remotely operated vehicle. The monitoring shall incorporate, if deemed necessary by the licensing authority, physical, chemical and biological investigations, to assess the status of the authorised deposits and their impact in the receiving environment. The scope, frequency and spatial extent of the investigations shall be approved by the licensing authority. Successive operations at each of the berth sites will only require monitoring to be undertaken if the new operation results in any additional deposits on the seabed.
- FEPA condition 15: The licensee shall submit where appropriate, written reports to the licensing authority detailing the results of the monitoring. The written reports shall be prepared by the licensee detailing, where appropriate, the status of the authorised deposits and their impact on the receiving environment and their position (latitude and longitude to three decimal places of minutes). The written report should also detail the nature, quantity and fate of all the deposits that are relocated and/or replaces on the seabed during maintenance and operations. Previous monitoring reports may be amended by the addition of an appendix detailing new deposits on the seabed.
- FEPA supplementary condition a: The licensee will ensure they comply with the environmental monitoring plans submitted by the licensee in support of the FEPA application. Prior to installation the monitoring plan must be signed off and held by Marine Scotland.
- FEPA supplementary condition b The licensee will produce a report within 8 weeks of the monitoring being completed at the EMEC site. It should review all data collected through the EMP to determine any associated impacts. This report will be submitted to the licensing authority (Marine Scotland).
- FEPA supplementary condition c The licensee will ensure a Marine Mammal Observer (MMO) is in place on the installation vessel during all noisy installation operations likely to cause disturbance.
- FEPA supplementary condition d The licensee must ensure that the DP vessel operator follows the soft start protocol as outlined in the EMP to ensure that basking sharks, cetaceans and seals within the vicinity of the noisy works have sufficient time to move out of the 500 m buffer zone.
- FEPA supplementary condition e The licensee will undertake monitoring in accordance with the EMP which will be signed off by SNH and Marine Scotland prior to installation.
- FEPA supplementary condition f If through monitoring it is determined that the device could have an adverse impact on the site integrity then any further mitigation measures may be required at the discretion of Marine Scotland. CPA Must comply with requirements of FEPA license.
In December 2011, ANDRITZ HYDRO Hammerfest successfully deployed its 1 megawatt (MW) pre-commercial tidal turbine named HS1000 at EMEC’s tidal test site to validate the technology for future tidal power arrays. The device delivered its first energy to the grid in February 2012. The prototype was in operation for more than 17,000 hours, delivering over 1.5 GWh to the grid and showed 98% availability during testing. The device was removed from the EMEC site in 2015.
Key Environmental Issues
Baseline studies for the Fall of Warness test site were performed by EMEC and can be found here.
- Harbour seals from Sanday SAC, approximately 30 km from the proposed test berth, may potentially use the Fall of Warness to travel between haulout sites. The Seal Skerry harbour seal haulout is located 3 km to the north of the proposed test berth.
- Grey seals from Faray SAC, approximately 10 km from the proposed test berth, may potentially use the Fall of Warness to travel between haulout sites. Muckle Green Holm grey seal colony is located 3 km to the south west of the proposed test berth. EMEC observations of marine mammal surface activity indicate grey seal concentrations may be greatest closer to the coast.
- Harbour porpoise are likely to be present at the proposed test berth
- Cetaceans are likely to be present at the proposed test berth
- Little Green Holm cormorant breeding colony is located approximately 3.5 km to the south of the proposed test berth
- Basking sharks likely to be present at the proposed test berth
Papers, Reports, Research Studies
- Baseline conditions of the site are provided by EMEC in the EIA carried out for the Fall of Warness test site
- HS1000 1 MW Tidal Turbine at EMEC: Supporting Documentation
Post-Installation Monitoring: HS1000 at EMEC
|Stressor||Receptor||Study Description||Design and Methods||Results||Status|
|Collision||Marine Mammals||Collision monitoring using video||Nacelle mounted video camera aligned almost vertically to capture the entirety of each blade. Purpose being to capture any collision events that may occur. To be used along with the strain gauge data.||Not available|
|Collision||Marine Mammals||Collision monitoring using video strain gauges||At least two strain gauges built into each blade. Data obtained from the initial 4 weeks of operation and testing will be fully reviewed. Any ‘unusual’ strain events were investigated using the video footage.||Not available|
|Noise||Marine Mammals||Marine Mammal Observations||A vessel based Marine Mammal Observer (MMO) following protocol developed by EMEC will be present during any ‘noisy’ operations during installation. Noisy operations are defined as any time a DP vessel is on site. The MMO will look for the presence of marine mammals and basking sharks as well as slicks in the wash of the vessel that could indicate seal strikes.||Not available||Completed (2011)|
|Noise||Marine Mammals||Acoustic survey of the operation turbine commissioned to Xi Engineering Consultants||The monitoring will provide acoustic information for assessment of the potential effects on local cetaceans, pinnipeds, mammals and other wildlife. The methodology for the assessment has not been published to date.||Not available|
|Displacement||Marine Mammals||Displacement monitoring using EMECs wildlife observation data||The design and method of EMECs wildlife observations are given on the Fall of Warness page (http://tethys.pnnl.gov/project-sites/emec-fall-warness-grid-connected-tidal-test-site).||See the Fall of Warness page http://tethys.pnnl.gov/project-sites/emec-fall-warness-grid-connected-tidal-test-site||Completed|
|Changes in Flow||Physical Environment||ROV survey of benthic habitat||Post installation ROV survey using a similar methodology to the pre installation survey to determine the effect of the turbine on the seabed. This survey will be carried out at a similar time of year to the pre installation survey to minimise seasonal variation. Post decommissioning survey using a similar methodology as the previous two benthic surveys.||Not available|