Marine Energy Resource

Ireland's offshore marine energy resource is considered substantial by European standards and there is significant potential in harnessing these resources to generate electricity. 

Wave Observations

Real time wave observations are collected at the Atlantic Marine Energy Test Site (Full Scale) and the Galway Bay Test Site (1/4 Scale). Observations include:

  • Peak Period
  • Upcross Period
  • Peak Direction
  • Significant Wave Height

Observations of waves are collected from the Weather Buoy Network buoys M2, M3, M4 and M6 which include:

  • Significant Wave Height
  • Wave Period
  • Max Wave Height
  • Max Wave Period
  • Mean Direction

Oceanographic Modelling

Marine Institute Oceanographic Services provide wave modelling support to the Ocean Energy Industry via the SWAN wave model producing weekly forecasts. The numerical wave model, SWAN, is run for a 0.025 degree grid every weekday to produce a 6 day forecast. The model uses NCEP GFS for wind forcing and FNMOC Wave Watch 3 data for the wave boundaries. The forecast is generated for research purposes and for comparison with measured wave parameters. The Marine Institute does not guarantee to make model output available on its web site. The predictions should not be used for safety critical applications.

The SWAN wave model produces forecast data on:

  • Wave Height and Direction
  • Wave Period and Direction
  • Wind Speed and Direction

In addition, the modelling team produce "Monthly Model Means" of significant wave height, mean wave direction and mean wave period.

Accessible Wave Energy Resource Atlas

The atlas published in 2005 describes an initial comparison between several years of hourly wave forecasts (using WAM) on a grid of points located off the Irish coast with corresponding records from a number of buoys installed in recent years. Based on the level of agreement found the wave forecasts were then modified slightly and used to estimate and map the mean annual power and energy resources at the theoretical, technical, practicable and accessible levels. 

Data in the map gallery produced by the “Wave Atlas” consists of wave estimates generated by the Pelamis model including:

  • Annual Average Wave Height (m)
  • Annual Average Wave Period (s)
  • Annual Average Power Practicable (MW)
  • Annual Pelamis Energy (MW)
  • Seasonal Average Power Flux kW (kW)
  • Seasonal Hydro Energy MW hours (MW)
  • Seasonal Pelamis Average Power MW (MW) 
  • Seasonal Pelamis Energy GW hours (GW)

Ireland's offshore wind resource is considered substantial by European standards and this potential is being realised by the existing installation of the Arklow Bank Wind Park in the Irish Sea as one of the World's first offshore wind parks.

Sustainable Energy Authority Ireland Wind Atlas

Offshore wind speeds have been mapped to a distance of 25 km from the Irish coast. The wind resource displayed has been constrained to exclude areas where wind energy projects will not be permitted such as areas where seabed cables and gas pipelines are located, indicative navigation channels, Department of Transport traffic separation and exclusion zones, Department of Defence Danger Areas and near-shore anchorage area.

The Wind Atlas can assist with the offshore wind planning process and act as a data resource to developers and policy makers alike. 

The wind maps show the predicted mean wind speed at a heights of 50 m – 100 m above ground level and the predicted mean wind power density at the same heights. The mean speed and power describe different aspects of the wind resource, and both can be useful in different ways. The mean speed is the easier for most people to relate to and is consequently the more widely used. However, it does not directly measure the power-generation potential in the wind. Some experts regard the mean wind power, which depends on the air density and the cube of the wind speed, as a more accurate indicator of the wind resource when assessing wind project sites. Generally speaking, commercial wind power projects using large turbines require a mean speed of at least 7 m/s or mean power of at least 400 W/m2. Small turbines are designed to operate at lower wind speeds, and may be useful at mean speeds (at 30 m height) as low as 5-6 m/s.

Tidal and Current Energy Resources around Ireland

The Sustainable Energy Authority Ireland conducted a study to identify the potential for cost effective exploitation of the tidal stream and marine current energy resource and to prepare detailed analysis of areas considered to have the greatest potential for the extraction of tidal energy. This report considers a calculation of the tidal and marine current energy resource available with existing technology and to assess the additional contribution which future technology is expected to make. The report evaluates deep water areas (exceeding 40m) which have high current velocities for the purpose of developing second-generation deep water devices. The report extends the methodology for estimating the renewable energy resource in Ireland to provide a medium term development potential (or estimated contribution) for the years 2010 and 2020, including the anticipated resource/cost curve per unit of energy produced.

The tidal currents are generally low along the west and south coasts, are relatively strong in the St George’s and North Channels and are moderate along much of the east coast. The current strengths are considerably influenced by the local bathymetry. One part of the flood travels up the west coast and around the north of Ireland, whilst the other part floods north up the Irish Sea. The tidal streams meet in the area of St John’s Point. A consequence of the way the tides flow around Ireland is that there is a phase difference in the times of high and low water along different parts of the coast. 

  • A significant proportion of the tidal and marine current energy resource is to be found on the east coast of Ireland. The resource on the west coast is concentrated in the Shannon Estuary. 
  • Tidal energy technology is in the early stages of development and stream velocities of at least 2.0m/sec are required for efficient generation. With further technological development, efficient 
  • generation from stream velocities of 1.5m/sec should be practicable by the year 2015. 
  • When technical, physical, institutional and commercial viability constraints are applied the resultant energy resource, referred to as the Viable Resource, reduces to approximately 0.915 TWh/year and this represents 2.18% of the predicted electricity consumption for the year 2010. This figure could rise to 6.27% of the predicted electricity consumption between 2010 and 2015. 
  • Environmental constraints, specific to each site, may also apply and in such cases exploitation of the viable resource may be affected. 
  • Many devices are in their infancy as development remains at an early stage. Largely due to commercial confidentiality, detailed information on test results is not widely available. 
  • A re-assessment of generating viability after a period when further test data should be available is recommended. 

Marine Institute HQ                                    Sustainable Energy Authority Ireland

Rinville,                                                      Wilton Park House

Oranmore,                                                 Wilton Place

Co. Galway,                                               Dublin 2

Ireland                                                       Ireland

Tel: +353-91-387200                                Tel: +353-1-8082100

Email: datarequests@marine.ie               Email: ocean.energy@seai.ie

 

Arklow Bank Windfarm

Arklow Bank Windfarm image

Arklow Bank wind farm from South beach.

Arklow Bank Wind Turbines

Arklow Bank Wind Turbines image

Arklow Bank Wind Turbines

European Wave Energy Atlas

European Wave Energy Atlas image

European Wave Energy Atlas average theoretical wave power in kW

SEAI Wind Atlas Mean Wind Speed at 50m height

SEAI Wind Atlas Mean Wind Speed at 50m height image

Offshore Mean Wind Speed maps measuring wind maps in metres per second recorded around the coast of Ireland.

SEAI Wind Atlas Offshore Mean Wind Speed at 75m height

SEAI Wind Atlas Offshore Mean Wind Speed at 75m height image

Sustainable Energy Authority Ireland offshore mean wind speed recorded at 75m heights.

SEAI Wind Atlas Offshore Mean Wind Speed at 100m height

SEAI Wind Atlas Offshore Mean Wind Speed at 100m height image

Sustainable Energy Authority Wind Atlas offshore mean wind speeds recorded at 100m heights.

Depth Averaged Peak Spring Tidal Currents around Ireland

Depth Averaged Peak Spring Tidal Currents around Ireland image

Map of tidal pattern around Ireland. The tidal currents are generally low along the west and south coasts, are relatively strong in the St George’s and North Channels and are moderate along much of the east coast. The current strengths are considerably influenced by the local bathymetry. One part of the flood travels up the west coast and around the north of Ireland, whilst the other part floods north up the Irish Sea. The tidal streams meet in the area of St John’s Point. A consequence of the way the tides flow around Ireland is that there is a phase difference in the times of high and low water along different parts of the coast.

Inishtrahull Sound Tidal Pattern

Inishtrahull Sound Tidal Pattern image

Tidal and Current Energy Resources report map of the tidal resource in Ireland at Inishtrahull Sound. Inishtrahull is located at the most northerly point of Ireland off Malin Head.

Codling and Arklow Banks Tidal Pattern Irish Sea

Codling and Arklow Banks Tidal Pattern Irish Sea image

SEAI Tidal and Current Resources report map of the tidal pattern in the Irish Sea in the Codling and Arklow Banks.

ESB WestWave Area Of High Potential Wave Resource

ESB WestWave Area Of High Potential Wave Resource image

Map of Ireland with areas of high potential wave energy resources as analysed by the ESB WestWave project.

Strangford Lough Tidal Turbine

Strangford Lough Tidal Turbine image

Strangford Lough tidal turbine device.