The history of wave energy conversion stretches back to 1799 when Pierre-Simon Girard and his son filed the first known patent application for harnessing energy from waves. Modern wave technologies use a range of different approaches including point absorber buoys, surface attenuators, oscillating water column, oscillating wave surge and overtopping devices. For more information on these technologies and how they work, please click here.
Saoirse intends to utilise a surface point absorber-type wave energy converter array developed by CorPower Ocean. This technology, inspired by the pumping of the human heart, consists of floating surface buoys, anchored to the seabed by a pre-tensioned system, that rise and fall with wave motion. The resulting mechanical energy is converted to electricity for export to shore through a system of inter-array and export cables.
A wave energy array, such as that proposed for the Saoirse Project, is a series of wave energy devices linked via electrical power cables to a central collection hub with an electrical power connection to shore through an export cable. The export cable will then be connected to the national grid and incorporated into the energy distribution network.
Wave energy has been pursued as a power source for many years because of the multitude of potential benefits associated with the technology, some of which are given below:
Our oceans behave like wind energy batteries. With growing reliance on wind energy, it is important to find complimentary energy sources that regulate and smooth out renewable energy production so that spikes and troughs in electrical grid supply can be avoided.
Waves are created during sustained periods of wind interaction with our oceans. The energy imparted by the wind is efficiently stored and transported by ocean waves. These waves usually lag behind the wind systems that created them, providing the opportunity when augmented with wind energy to better regulate renewable electrical power production.
The Irish government’s pledge to supply 70% of the country’s power from renewables by 2030, with a view to being fully carbon neutral by 2050, highlights the need for innovation and diversification in our renewable energy sector. Wind energy, both onshore and offshore, currently provide the majority of renewable energy to the Irish grid at 16.3% but only 24.3% of Irish energy inputs to the grid comes from renewable sources (based on 2018 figures*).
With a long way to go to reach our national renewable energy targets, Ireland must look beyond just wind energy to realise these goals. Wave energy provides a reliable and abundant alternative that can complement wind energy production by balancing grid demand, but it requires projects like Saoirse to demonstrate this potential and pioneer its development.
*Based on SEAI electricity data and figures: https://www.seai.ie/data-and-insights/seai-statistics/key-statistics/electricity/
No. The proposed Saoirse project represents a breakthrough for WEC technology and will be a landmark in the history of wave energy conversion. At present, Saoirse is the first project where wave energy converters will be utilised at a meaningful scale for domestic use.
The Simply Blue Group business model and specialism is to pioneer new blue economy technologies. The proposed pioneering step for wave energy is made possible by close relationships between Simply Blue Group and the world’s leading wave energy technology developers and careful independent staged review of WEC technology status and progression.
CorPower Wave Energy Converters are point absorber type, with a heaving buoy on the surface absorbing energy from ocean waves. The buoy is connected to the seabed using a tensioned mooring system. Novel phase control technology makes the compact devices oscillate in resonance with the incoming waves, strongly amplifying the motion and power capture. The system has improved survivability in storms, thanks to its inherent transparency to incoming wave energy in long storm waves.
The concept offers five times more energy per ton of device compared to previously known wave technologies. The high structural efficiency allows for a large amount of energy to be harvested using a relatively small and low-cost device, reducing the equipment (CAPEX) cost per MW capacity. The compact and lightweight WECs are also easy to install and maintain using low-cost vessels, bringing down operational (OPEX) costs. All together this provides competitive cost-of-energy.
Generators and power electronics are standard components known from the wind industry, enabling well known grid connection architecture. The product concept is optimized for clusters, where the electricity is collected from an array of WECs into a collection hub. Each hub delivers grid quality electricity with standard 33/66kV electrical connection commonly used in offshore wind, with a single control and data acquisition interface over fibre and radio-link to the hub. Each WEC operate autonomously by a programmable logic controller located inside the device.
More information on the CorPower technology can be found here.
Through CorPower Ocean’s HiWave-3 demonstration project a large scale (1:2) WEC system was designed, manufactured and tested in two steps between 2015 and 2018, first by dry Hardware-In-the-Loop rig testing in grid connected configuration (Stockholm) and then by sea trials at EMEC Scapa flow test site in a micro-grid configuration (Orkney).
After 18 months of combined dry and ocean testing of the half scale ’C3’ Wave Energy Converter (WEC) in Stage 3 during 2018, CorPower and project partners had taken important steps towards proving commercial viability of wave energy. By verifying the ability to solve the two major challenges for wave energy, storm survivability combined with significant power production, a major demonstration milestone was completed.
CorPower Ocean’s more recent HiWave-5 project off Portugal marks a final push towards commercialisation as part of a broader mission to make wave energy competitive with wind and solar by 2030.
This landmark project, currently under way, sees CorPower’s first commercial-scale C4 Wave Energy Converter deployed off the coast of Agucadoura, northern Portugal. This will later form part of a larger four-system WEC array, and one of the world’s first active wave farms generating energy to the grid. HiWave-5 aims to deliver certified and warrantied WEC products to the market by 2024, propelling wave energy into the future green energy mix as a bankable technology.
Simply Blue Group, headquartered in Ireland, was established in 2011 and has assembled an experienced board and executive team for the purposes of developing both offshore wind and wave energy farms. Simply Blue Group are currently developing floating offshore wind projects in Ireland, the UK, Spain, Portugal, Italy, US, Canada, and Australia, among others.
In Ireland, SBG are developing the Emerald Floating Wind project (www.emeraldfloatingwind.com) off the south coast of Cork. Emerald envisions the transformation of the maritime landscape in the area of the Kinsale gas platform into a zone for the production of clean, renewable offshore wind energy.
Additionally, Simply Blue are progressing Western Star, another floating offshore wind farm off the Co. Clare Coast, west of the Saoirse WEC site. Along with Emerald, this c. 1.3GW project aims to help to Ireland reach the ambitious clean energy targets set by the recent Programme for Government and the Climate Action and Low Carbon Development Bill 2021. Grid infrastructure around the coal fired thermal power station at Moneypoint will be utilised by both Western Star and Saoirse as the fossil fuel burning facility is phased out, paving the way for green energy to be effectively distributed.
Both Irish floating wind projects are being developed jointly with EDF Renewables.
The Marine Area Planning (MAP) Act (2021) has let to the incorporation of a new authority to oversee offshore infrastructural developments called the Marine Area Regulatory Authority (MARA). Saoirse will require a Maritime Area Consent (MAC) through this authority with an Environmental Impact Assessment process to follow and an application for Development Consent to An Bord Pleanála or the local planning authority.
A range of surveys may need to be carried out to inform the environmental and engineering investigations related to the development of the Saoirse project including geophysical, geotechnical, metocean, ecological, geological, and archaeological. These surveys, and the equipment and techniques proposed, are detailed within the Schedule of Works section of the Foreshore Site Investigation Licence application which was submitted to the Department of Housing, Local Government and Heritage in 2021 and is available on their website here.
It should be noted that it is likely that not all of these surveys will be required but initial data will go on to better inform subsequent survey requirements. Any surveys that have the potential to impact other marine users will be communicated and consulted upon with them, in advance of works taking place, to minimise disruption.
Some baseline environmental surveys for Saoirse have already been carried out with 2 years of data collected from monthly flights collecting ultra-high definition footage of the proposed area and its surrounds to help inform population distributions and movements of seabirds and marine mammals in and around the site. These will help to inform the Environmental Impact Assessment (EIA) process. Intertidal bird surveys at potential landfall sites were also run in parallel with the aerial surveys. Further environmental survey work is planned to better inform the EIA process.
Geophysical surveys to inform the engineering design are also planned and are expected, potentially covering two summer seasons (initial geophysical surveys and detailed surveys) and running in conjunction with geotechnical and metocean surveys.
The WEC units planned to be utilised for Saoirse will essentially consist of a large buoy, floating on the surface and bobbing up and down with the motion of the waves. With a site location of c. 4km offshore, visual intrusion from the shoreline would be minimal.
Visualisations simulating how the Saoirse WEC site will look from shore have been produced, which can be downloaded here
Sailing between individual WEC devices is subject to compliance with all Marine Safety legislation and compliance with any requirements from the Department of Transport (DTTAS).
Due to the high relative density of the WEC units (when compared with other ORE installations such as offshore wind turbines), it is unlikely that sailing will be permitted between them as this could pose significant health and safety risks and the risk of damage to boats and/or WEC infrastructure. However the proposed footprint of the c. 5MW WEC array will be approx. 0.15km2 and as such, take up a relatively small amount of the marine space.
Currently, a WEC array would be expected to have an operating life of approximately 20-25 years depending on weather and sea conditions.
The Saoirse project team is fully committed to continually engaging with stakeholders and local communities from a very early stage to ensure that everyone’s voice is heard and respected right through the process. A wide range of stakeholders will be consulted throughout the project including fishers, shipping organisations, local community groups, recreational marine users, environmental groups, and government agencies. This consultation process is already well under way. Interested parties can get in contact here.
The Saoirse site, off the west coast of Ireland, was chosen after initial, desk-based assessments of wave resource, grid connection, seabed characteristics, among many other considerations.
The National Marine Planning Framework (NMPF) which was ratified in 2021 promotes inclusion and coexistence between multiple users of the marine space. The Saoirse project adopts a similar ethos of coexistence.
We recognise the importance of engaging as early as possible with the local fishing community to ensure ways are found to minimise the impact of the offshore renewables on fishing. To accommodate local fishers the wind farm and WEC array can be designed and laid out in a way that reduces its impact.
Seismic surveys, using air-guns to create a sound wave that gets reflected back off substrate rock layers, may be employed as part of the suite of geophysical surveys. Unlike seismic surveys carried out by oil or gas exploration companies, the Saoirse project team only needs to know the nature of the seabed to a shallow depth. This allows them to carry out the surveys using much less impactful soundwaves.
The impacts of seismic surveying techniques have been analysed and studies have shown that there is little significant impact on fish and squid behaviour as a result of these works. The temporary nature of the surveys, coupled with the limited impacts, minimise the risk to these populations*. Furthermore, a study on lobster and scallop mortalities due to seismic exposure showed no discernible effects as a result**.
*Fewtrell, J.L., & McCauley, R.D. (2012). Impact of air gun noise on the behaviour of marine fish and squid. Marine Pollution Bulletin, 64(5), 984-993.
**Day, R.D. et al. (2016). Assessing the Impact of Marine Seismic Surveys on Southeast Australian Scallop and Lobster Fisheries, Final Report 2012- 008-DLD (FRDC, 2016).
Seismic surveys, using air-guns to create a sound wave that gets reflected back off substrate rock layers, are employed as part of the suite of geophysical surveys. Unlike seismic surveys carried out by oil or gas exploration companies, the Saoirse project team only needs to know the nature of the seabed to a shallow depth. This allows them to carry out the surveys using much less impactful soundwaves.
Laboratory studies have shown limited effects on juvenile seabass as a result of exposure to seismic noise*. Other studies on the effects of seismic disturbance on the development of lobster larvae in Australia have shown no measurable negative effects with noises of up to 227 dB**.
*Radford, A. N., Lèbre, L., Lecaillon, G., Nedelec, S. L. & Simpson, S. D. (2016). Repeated exposure reduces the response to impulsive noise in European seabass. Global Change Biology, 22, 3349-3360.
**Day, R.D., McCauley, R.D., Fitzgibbon, Q.P. & Semmens, J.M. (2016). Seismic air gun exposure during early-stage embryonic development does not negatively affect spiny lobster (Jasus edwardsii) larvae. Scientific Reports, 6(1).
As much as is possible, cables will be buried below the seabed which should reduce or eliminate the risk of snagging. However, there may be uneven parts of the seabed where cables cannot be buried, and this could create a risk of fishing gear becoming snagged.
Some parts of the cables may require additional protection measures such as mattressing or rock dumping which could represent an increased risk and every effort would be made to design these protections to make them trawl proof.
As projects such as this represent a large amount of capital investment, there is considerable opportunity for job creation within the local community and along the Atlantic coast. The Saoirse project will support local job creation at all stages, including by working with the fishing industry to explore opportunities for future employment and by actively encouraging local content in our supply chain.
There will be employment opportunities in each of the project phases. The most significant employment opportunities will come during the operations phase of the WEC array which will require a team to service the wave converters on a daily basis. These jobs will be long-term (up to 30 years), permanent and will be local. We anticipate that this project will have a transformative positive impact on local communities along the coast, creating jobs and boosting the supply chain.
As no WEC projects of this scale are currently in operation, direct comparisons are not possible but a report carried out as part of the EirWind study found that in 2030, 2.5-4.5GW of domestic offshore wind development would support between 4,620 and 8,316 jobs in the domestic supply chain and generate between €325m and €585m in Gross Value Added (GVA)*. Local benefits from other Offshore Renewable Energy (ORE) projects such as Saoirse, while on a smaller scale, will encourage local supply chain development and enhancement which will help to build the local economy.
The Saoirse project team believes strongly in working with local businesses and will actively encourage and prioritise local supply chains wherever possible. Our philosophy is to develop and nurture the local supply chain encouraging local suppliers and communities to get involved with the project. To aid this, we are undertaking a study into what components of the WEC units could potentially be sourced or manufactured locally with a view to engaging with potential suppliers directly to help them get involved.
Offshore Renewable Energy (ORE) projects represent a massive capital investment into local areas. A study in the UK found that a 500MW Celtic Sea Floating Offshore Wing site could generate 1,381 construction stage jobs and 33 O&M stage jobs in the Welsh and SW region and £630M in direct local investment during the construction phase with a further £8.8M annually for O&M*.
*ORE Catapult Report – Benefits of Floating Offshore Wind to Wales and the South West, Supply-chain report.
The WEC farm will interface with the shore in several areas: (i) an onshore landfall for the export cable and associated cabling back to an onshore substation and (ii) an operations and maintenance base to service the WEC array. Both of these elements of the project will be subject to the onshore planning process and will be undertaken with a view to minimising onshore disruption, whilst also maximising the local supply chain opportunities.
A WEC array may have a range of potential impacts, both positive and negative, on the receiving habitat and the organisms that live there. Impacts are likely to be greatest during the construction and installation phase of the works, due to benthic disturbance at anchor points and along the routes of the inter-array and export cables. These impacts will be temporary in nature and will be designed in such a way as to minimise the impact on wildlife.
Alteration of waves and currents in the lee of the WEC array will occur but studies have shown that at the device spacings (150m or 16xD) and distance from shore (4km) proposed for Saoirse, these alterations are likely to be insignificant at the coast.*
The project will be subject to a full Environmental Impact Assessment and Appropriate Assessment as it progresses through the planning process and the project will implement any mitigation measures that have been proven to be effective where there is a real risk to the environment.
* Rijnsdorp, D.P., Hansen, J.E. & Lowe, R.J. (2020). Understanding coastal impacts by nearshore wave farms using a phase-resolving wave model. Renewable Energy, 150, 637-648.
No, the project development will include a dedicated Archaeological Risk Assessment with studies undertaken to identify shipwrecks using geophysical survey techniques. Once a shipwreck database has been established for the site, Simply Blue Energy will aim to avoid all areas of archaeological significance.