The announcement of a proposed 12MW installed capacity tidal stream project by Normandie Hydroliennes, a French company, and the prediction by Michael Shanks MP, the UK energy minister, in The UK 2024 Ocean Energy Review that “with 130MW of tidal stream on course to be deployed in UK waters by 2029, tidal stream will play a growing role in the 2030 energy mix”, the question regarding Ireland’s lack of progress in marine energy exploitation has to be raised once more.
This paper will review the potential for and the progress in marine energy extraction by our nearest neighbours in the UK and France.
The tidal stream project in Normandy
Normandie Hydroliennes posted an update on a tidal-stream electricity-generating project, named 'NH1', which has been in the development stage since 2020. The project's location is 3.4km west of the coast of Cap de la Hague in Normandy, in an area with very strong currents.
NH1 will use four Proteus AR3000 horizontal axis turbines, each having a capacity of 3MW. This 12MW installed capacity will supply 34GWh of energy a year, enough to meet the needs of 15,000 homes by 2028.
NH1 is a collaboration of three groups:
- EFINOR, an engineering group focused on metalworking, mainly in the naval and energy sectors.
- Proteus MR, based in Bristol, in the UK, with expertise in the development, construction, and operation of advanced tidal energy technology.
- Normandie Participations is an investment fund of the Normandy region, supporting regional startups and SMEs in their development projects through fundraising operations within the region (https://normandiehydroliennes.fr/en/le-projet-nh1/).
Other benefits: NH highlights other benefits; a total of 80% of the construction value of the project will be produced in France. The reminder will come from Europe. About 400 local, direct and indirect jobs are proposed. EU funding of €31.3m has been secured for the project.
Future expansion: Project NH1 deployment is in the Channel sea current of Raz Blanchard, one of the most powerful in the world, according to Normandie Hydroliennes. With a development potential of about five to six gigawatts (GW), it could produce 15 to 18 terawatt hours (TWh), supplying electricity to eight million people.
The turbine: The AR3000 turbine has an interesting history, being a 'descendant of the first commercially deployed tidal stream turbine, 'SeaGen' in Strangford Lough in Northern Ireland, as illustrated in Figure 1.
Figure 1: Turbine development timeline. Image: Proteus MR.
The 'SeaFlow' turbine, as illustrated in Figure 1, was developed and deployed by Peter Fraenkel MD of Marine Current Turbines (MCT) at a depth of 25m some 1.1km off the Foreland Point lighthouse in Devon.
This was an experimental project only, as it did not supply power to the national grid, but it provided useful data that led to the deployment of 'SeaGen' in Strangford Lough.
MCT was acquired by Siemens. SAE Renewables (Simec Atlantis Energy), in turn, acquired MCT from Siemens. Proteus MR emerged as a result of a management buyout (MBO) of the Advanced Tidal Engineering & Services Division of SAE Renewables.
Proteus MR owns the AR series of tidal stream turbines, which range in capacity from 1-3MW. AR1500 & AR2000 turbines are deployed in the MeyGen project. MeyGen is located between the northeast of Scotland and the island of Stoma, south of Orkney. This is a three-phase project. Phase 1A is currently operational and consists of the deployment of 4 x 1.5MW turbines in a multi-turbine array.
The turbines, a combination of AR1500 and Hammerfest AH1000 turbines, each mounted on a 250-350 tonne foundation, delivered 17GW/h to the grid in 2019. Phase 1B, now in construction, will add two AR2000 turbines to the array.
The European Marine Energy Centre
MeyGen is one of the projects that have emerged under the aegis of the European Marine Energy Centre (EMEC). It was established in 2003 with funding from the Scottish government, the British government, and the EU to kick-start a marine industry in the UK by providing 'pathways to commercialisation'.
The EMEC provides both wave and tidal test facilities with access to the grid for client industries in the marine energy sector. Its extensive tidal stream client list includes Orbital Marine, Magallanes, and Verdant Power.
Verdant Power’s three Gen5 turbines were later deployed at the Roosevelt Island Tidal Energy project in New York. Verdant Power secured $6m in funding in 2018.
Atlantis Resources' AR1000 turbine was first deployed at the EMEC. It is the world’s first such facility and the only accredited test centre for marine renewable energy worldwide.
The EMEC now supports a range of activities, including offshore and floating wind, hydrogen, and decarbonisation projects.
UK government agencies and the European Union have provided funding to the tune of £42m to the EMEC.This investment has paid off. An economic assessment by Biggar Economics, a consultancy that provides economic analysis and advice to central and local government, showed that, as a result of EMEC’s operations over the last two decades, £370m gross value added (GVA) has been added to the British economy. This represents about £9 returned to the economy for every £1 of public investment.
Tidal energy prospects
Normandie Hydroliennes is confident of the success of the project, posting on its website that “tidal energy remains an untapped renewable energy source, which represents a huge opportunity for the Europe and France 2030 plan, with significant economic, environmental and social benefits”.
This view of tidal stream electricity generation is echoed by a paper published in Engineers Journal entitled 'High stakes in high tides: Tidal energy and its effect on green power and biodiversity' on March 10, 2025, by Alireza Eftekhari and Anne Marie Power, University of Galway.
The authors state that “Tidal energy’s predictability makes it an ideal complement to intermittent renewable sources like wind and solar, helping stabilise grids and reduce the need for fossil fuel-based back-up power. This reliable energy source can play a crucial role in transitioning to a fully renewable energy system, while also stimulating local economies by creating jobs and fostering innovation”.
The Policy and Innovation Group at the University of Edinburgh published a report entitled 'The 2024 UK Ocean Energy Review'. In the report, Professor Henry Jeffrey, who is the head of the group and one of the authors, stated that “2024 has been a year of significant progress in the UK ocean energy sector. I’m delighted to see that the pipeline of tidal stream projects awarded through the CfD (contracts for difference) scheme has now expanded to over 120 MW, which will ensure that sector makes a meaningful contribution to the UK’s 2030 clean power targets” (https://www.emec.org.uk/2024-uk-ocean-energy-review/).
Tidal stream energy extraction in Ireland
The first tidal stream turbine installation in Europe was in Strangford Lough in Northern Ireland.
The installation consisted of a fixed base with two 600KW turbines. The project was initially approved for a five-year life cycle. This was later extended by a further five years. Decommissioning was completed in 2019. This was a successful project, which provided electricity to 1,500 homes. However, the focus on marine energy extraction was now firmly set on the EMEC in Orkney, resulting in no further developments in Strangford.
At present, the island of Ireland has no installed tidal stream energy capacity.
Figure 2, published by the EMEC, illustrates the tidal stream resources around Europe with a focus on the British Isles (https://www.emec.org.uk/marine-energy/).
Figure 2: Tidal resources around Europe. Image: The EMEC.
The last (and only) tidal resource survey for Ireland was completed in 2004 by the Sustainable Energy Authority of Ireland.
The most advantageous sites for tidal-current energy exploitation identified in the 2004 report are the north/east coast with a viable energy resource of 273GWh per year; Strangford Lough with 130GWh/y; Tuskar Rock and Carnsore Point with 177GWh/y; Shannon Estuary with 111GWh/y; Codling & Arklow Banks (70 GWh/y); Inishtrahull Sound (15GWh/y); and Ram Race – Copeland Islands (125 GWh/y).
The Strangford Lough site would be the most obvious location for a revival of the tidal stream sector in Ireland.
The experiences of the EMEC and Normandie Hydroliennes has demonstrated that, apart from providing clean and predictable electricity generation, the economic life of the region benefits.
In this country, I believe we are neglecting a valuable asset in terms of renewable energy and the potential to establish a marine energy sector.
Author: Michael Barrett PhD MIEI: barrett.mike1@gmail.com