Description
The Torr Head Tidal Scheme (the “Project”) was proposed by TVL to utilise the strong tidal resource on the north east coast of Northern Ireland for electricity generation. The scheme is proposed to have a capacity of 100 MW, consisting of an array of up to 100 underwater horizontal axis turbines, each with a generating capacity of between 1 and 2 MW. The project scope of works will include the installation of the turbines and their foundations, sub-sea export cables, ancillary onshore works and the connection of the generating station to the onshore electricity distribution network.
Location
The centre of the AfL is approximately 1km offshore at Torr Head on the north coast of County Antrim Northern Ireland. Water depths in the AfL range from 30 to 100m at LAT. Tidal currents within the AfL reach up to 5m/s.
Licensing Information
In 2015 the following applications were sent out to relevant legislation to gain approval of the offshore elements of the Torr Head Tidal project:
- Marine Licence under Part 4 of the Marine and Coastal Access Act 2009;
- Article 39 consent under the Electricity (Northern Ireland) Order 1992;
- Schedule 4 of the Marine Works (Environmental Impact Assessment) Regulations 2011; and
- Regulation 5(3) of the Offshore Electricity Development (Environmental Impact Assessment) Regulations (Northern Ireland) 2008.
In addition, a number of further licenses and consents were required throughout the initial stages of the scheme, some of which are outlined below:
- Consent from the NIEA for any discharges under the Water Act (Northern Ireland) 1972;
- Article 40 consent under Electricity (Northern Ireland) Order 1992 for onshore grid connection works; and
- A Bill in the Northern Ireland Assembly may be needed to address the potential interference with the public right of navigation in the area. This procedure can normally be addresses through the FEPA licensing process.
Consent requirements and supporting EIA Regulations applying to the offshore Projecta are summarized in the following table (sourced from Table 1-1 of the Torr Head Environmental Statement):
|
Offshore project component |
Consent |
Description |
Relevant EIA regulations |
Consenting authority |
|
Tidal turbines, Turbine Support Structures (TSSs), inter-array cables and export cables to shore |
Marine Licence under Part 4 of the Marine and Coastal Access Act 2009 |
A Marine Licence is required to deposit or remove any substance or object in or from the sea – or on or under the seabed. This includes marine renewable energy generating infrastructure |
Marine Works (Environmental Impact Assessment) Regulations 2011 |
DoENI Marine Division |
|
Tidal turbines |
Article 39 consent under the Electricity (Northern Ireland) Order 1992 |
Consent required for any proposal to construct or operate an offshore generating station wholly or partly driven by wind or water with a capacity in excess of 1 MW |
Offshore Electricity Development (Environmental Impact Assessment) Regulations (Northern Ireland) 2008 |
Department for the Economy (formerly Department of Enterprise, Trade and Investment (DETI)) |
In December 2016 the NI Department of Agriculture, Environment and Rural Affairs’ Marine and Fisheries Division issued TVL a Marine License (ref. ML115_15).
Project Progress
In October 2012, TVL was awarded an AfL from The Crown Estate (TCE) to investigate the feasibility of developing a commercial scale 100 MW tidal energy array in the waters offshore of Torr Head on the north coast of County Antrim in Northern Ireland (NI).
TVL submitted an application for consent to construct and operate the tidal array to the NI Department of Enterprise, Trade and Investment in 2015.
Unfortunately in July 2018, project partner OpenHydro’s parent company, Naval Energies, made the decision to liquidate OpenHydro. TVL’s project has not been consented since its application in 2015. The company TVL was dissolved as of January 2019.
TVL submitted an application for consent to construct and operate the tidal array to the NI Department of Enterprise, Trade and Investment in 2015.
Key Environmental Issues
There are a number of conservation designations in the area around the proposed project site. These include the European designations of Special Protection Area (SPA) and Special Area of Conservation (SAC), collectively known as Natura 2000 sites, and the national designation of Area of Special Scientific Interest (ASSI). Three sites were of particular concern for the proposed project; the Rathlin Island SAC, Rathlin Island SPA and Torr Head ASSI.
The Antrim Coastline, including Torr Head and its environs, hosts a number of marine and coastal bird species. The site qualifies under the EU Directive by supporting internationally important breeding numbers of the following seabird species: Razorbill (Alca torda), Guillemot (Uria aalge) and Kittiwake (Rissa tridactyla). The SPA also regularly supports over 20,000 breeding seabirds including puffin (Fratercula arctica), fulmar (Fulmarus glacialis), shag (Phalacrocorax aristotelis) and gannet (Morus bassanus).
Species such as puffin, razorbill, guillemot, gannet and shag are diving species and forage for their food underwater and as such are more at risk from collision with the moving underwater turbines. Species which are surface feeders, such as kittiwakes and gulls may be more at risk from disturbance from vessels, as are those species which rest or moult on the sea surface.
The Irish Whale and Dolphin Group (IWDG) manage a sightings database of all cetacean sightings in Ireland, totaling 13,000 records. This cetacean sightings data indicates that Harbour Porpoise, Bottlenose Dolphin, Common Dolphin (Delphinus delphis) and Minke Whale (Balaeanoptera acutorostrata) are present in the waters around Rathlin Island and Torr Head. An acoustic survey was undertaken at a number of test sites off the north Antrim and Rathlin Island coasts in waters up to 200m depth, approximately 10 km from the area of investigation. A number of likely Sperm Whale (Physeter macrocephalus) vocalizations were recorded, indicating that this species may be present in the area. However, it should be noted that sperm whales are a deep diving species and are therefore unlikely to be present close to shore in shallower waters.
The terrestrial habitats of Torr Head and its environs are typical of the North Antrim coast, which represents an extensive area of exposed hard cliff. The basalt and chalk maritime cliff and slopes represent a diverse range of communities including those associated with rock crevices and cliff ledges, and with a range of typical maritime grasslands and heath. Notable species on the basalt cliffs include Wilson’s Filmy-fern (Hymenophyllum wilsonii), Thyme Broomrape (Orobanche alba), Hare’s Foot Clover (Trifolium arvense), Zigzag Clover (Trifolium medium) and Common Juniper (Juniperus communis). The chalk cliffs support neutral and species rich calcareous grasslands. Plants present in the grassland include Pignut (Conopodium majus), Harebell (Campanula species), Kidney Vetch (Anthyllis vulneraria) and several orchid species.
Papers, Reports, Research Studies
Baseline Assessment: Torr Head Project
| Receptor | Study Description | Design and Methods | Results | Status |
|---|---|---|---|---|
| Marine Mammals | Potential effects to large mammals. | Desk based study (Literature Review). | The key potential impacts on marine mammals from the construction and operation of the proposed tidal array development are displacement, disturbance and collision risk. Most marine mammals use sound as a means of communication, orientation and detecting prey. The presence of a noise source over and above normal background noise levels has the potential to cause direct injury or to interfere with their ability to communicate, orientate or catch prey and as such maybe be impacted by noise. Turtles are also thought to be sensitive to sound emissions. | Completed |
| Fish | Potential effects to shellfish and fish stocks. | Desk based study (Literature Review). | Construction: Slow moving species such as basking shark may be susceptible to vessel strike. Effects on salmonids due to reduction in water quality and noise from construction activities which may impact migration routes. Operation: The proposed array of tidal energy devices has the potential to impact on elasmobranches and, possibly, salmonids through the effects of the Electro Magnetic Force (EMF) associated with the electro-magnetic fields created by the generation and transmission of electricity. Sources of EMF include the offshore turbine- generators and the associated cabling linking the tidal energy devices to a sub-station. Elasmobranches use their electro-receptive organs for prey detection, navigation and orientation and thus are sensitive. Decommissioning: Slow moving species such as basking shark may be susceptible to vessel strike. Water quality changes may also be relevant. | Completed |
| Birds, Seabirds | Potential impact to bird species. | Desk based study (Literature Review). | Construction: Many of the species listed, puffin, razorbill, guillemot, gannet and shag are diving species and forage for their food underwater and as such are more at risk from collision with the moving underwater turbines. Species which are surface feeders, such as kittiwakes and gulls may be more at risk from disturbance from vessels, as are those species which rest or moult on the sea surface. | Completed |
| Physical Environment | Potential effects on the physical environment. | Desk based study (Literature Review). | Construction: The installation and construction of the proposed 100 turbines is likely to have an impact on the hydrodynamic regime in the local area sedimentary regime, possibly including SAC features. The significance of this impact will need to be assessed in the EIA. Operation: Localised scouring around the base of the tidal turbine units may cause a loss of benthic habitat or smother the existing habitat due to deepening of seabed. The degree of scour will be dependent upon the final choice of foundation design. Decommissioning: The removal of 100 turbines may cause a change to the hydrodynamic regime and coastal processes of the local area and is likely to lead to a return to conditions that existed prior to installation. Foundation type will influence decommissioning methods and, once defined, the extent of impacts can be assessed. There is potential for short term habitat loss and smothering of the benthic community during the decommissioning phase, due to the anchoring and positioning of decommissioning vessels and barges. Again, the extent to which this loss is significant will depend upon recoverability. | Completed |
| Physical Environment | Potential effects to Terrestrial ecology including: Wilson’s Filmy-fern (Hymenophyllum wilsonii), Thyme Broomrape (Orobanche alba), Hare’s Foot Clover (Trifolium arvense), Zigzag Clover (Trifolium medium) and Common Juniper (Juniperus communis). | Desk based study (Literature Review). | Construction: The construction of an on-shore substation of 100MW capacity will require a footprint of approximately 25m x 50m. The substation’s footprint together with any further hard-standings required for site access will result in a permanent loss of terrestrial habitat. Operation: There are unlikely to be any effects to terrestrial ecology during the operational phase other than occasional maintenance visits. Decommissioning: It is anticipated that any land disturbed during construction of the project will be replanted and re-established as part of the decommissioning phase. | Completed |
| Physical Environment | Potential impact to benthic and inner tidal ecology. | Surveys of the seabed along the north east Antrim coast undertaken from 2000 to 2003. | Permanent direct loss of sub-tidal benthic habitat from the installation of tidal device foundation. The degree of impact will vary depending on the tidal device chosen. Depending on size, a gravity base may have a greater impact than a moored or pinned device. | Completed |
Post-Installation Monitoring: Torr Head Project
| Stressor | Receptor | Study Description | Design and Methods | Results | Status |
|---|---|---|---|---|---|
| Collision, Noise | Marine Mammals | Development of an adaptive management programme in order to confirm that predicted impacts are not significant | Where strategic monitoring is appropriate, TVL would look to a collaborative effort between the Project, wider industry, regulators and stakeholders to take this forward in the most efficient way for the interest of the Project and future projects elsewhere. Any monitoring strategy will also be informed by results available from already operational tidal projects (e.g. MeyGen). Collection of underwater noise measurements of the selected tidal turbine. The data collected will be used to validate the underwater noise modelling completed to inform the impact assessment. | Planned | |
| Collision, Noise | Fish | Additional monitoring for fish will be incorporated into the proposed adaptive monitoring strategy that is being developed for marine mammals. | Monitor interactions between fish and operational turbines in order to confirm that the predicted impacts are not significant. | Planned | |
| Attraction, Collision, Noise | Fish, Human Dimensions, Fisheries | Ongoing consultation with commercial fisheries | Monitoring outlined for fish ecology above will also be used to inform on-going consultation with the Portaleen Salmon Fishery should the fishery become operational again during the lifetime of the tidal array operation with a view to confirming that there are no significant impacts on the fishery. | Planned | |
| Changes in Flow | Physical Environment | Hydrodynamic modelling – coastal processes and seabed conditions. | Project-specific modelling of hydrodynamic effects is planned to investigate the potential for the turbines to cause localised turbulence on the sea surface. This has been identified as a navigational issue. | Planned |