Is world’s first artificial energy island a shape of things to come?
Off the coast of Belgium, Elia Transmission is constructing the world's first artificial energy island. Utility Week's sister title GridEx explores how the Princess Elisabeth Energy Island is harnessing digital tools to reshape offshore wind, improve interconnection and bolster grid resilience, including in the UK.
By Rob Horgan, GridEx & International Editor
Photo: Elia
Is world’s first artificial energy island shape of things to come?
Off the coast of Belgium, Elia Transmission is constructing the world's first artificial energy island. Utility Week's sister title GridEx explores how the Princess Elisabeth Energy Island is harnessing digital tools to reshape offshore wind, improve interconnection and bolster grid resilience, including in the UK.
By Rob Horgan, GridEx & International Editor
Being hit by 40km/h winds atop the rooftop balcony at Elia Transmission’s recently constructed Offshore Wind Centre is the perfect reminder of the energy generation potential offered by the North Sea. Located in the Port of Ostend, the centre looks out across the water with uninterrupted views to the horizon.
Beyond the line of sight, some 45km from the coastline, the world’s first artificial energy island is taking shape. It will sit at the centre of the Princess Elisabeth Zone, Belgium’s second offshore wind area, bundling power from future wind farms and sending it back to shore through high-voltage infrastructure.
The Princess Elisabeth Energy Island will host both high-voltage alternating current (HVAC) and high-voltage direct current (HVDC) equipment, export cables from offshore wind farms, and is intended to create a landing point for future hybrid interconnectors with neighbouring countries, including the Nautilus link to the UK (see below).
It has been heralded as a first-of-its-kind innovation. However, the project has not been without its challenges. Supply chain constraints have forced a redesign, the cost of the project has come under scrutiny, and political hold-ups mean the second phase of the project to host interconnectors has yet to be given the green light. The European Investment Bank has just signed a €1 billion (£840 million) green credit facility to keep the project on track.
Why build an island?
For Elia Transmission CEO Frederic Dunon, the goal of the island is simple: “Grid energy independence.”
He says that changes to the geopolitical landscape since the project’s inception mean that it is “needed more than ever”, adding that this summer’s heatwaves across Europe add to the business case to build the island and build it quickly to ensure there is more renewable energy on the grid. “We have no time to lose,” Dunon stresses.
The island will help facilitate Belgium’s offshore wind ambitions, and the rest of the world is watching on as it offers a practical test case for coupling offshore generation and interconnection.
The design, build and operation of the infrastructure hosted on the island utilises many digitalisation tools from digital twins to robot dogs. The construction of the island itself is also a triumph in civil engineering.
The Princess Elisabeth Island is a 6ha artificial island formed from concrete caissons filled with sand. Work to create the physical island has now been completed. It comprises 23 massive concrete caissons as the outer shell, each weighing about 22,000t and measuring roughly 58m long, 28m wide and up to 32m high. The civil works have been carried out by TM Edison, a joint-venture consortium comprising DEME Group (DEME Dredging and DEME Infra) and JanDe Nul.
This article first appeared in Utility Week's sister website, GridEx Global gridexglobal.com
Traditional offshore substations are normally steel platforms. However, that was deemed unsuitable in this instance due to the heavy weight of HVDC converters and associated grid equipment. A fixed island therefore offers more space and a stable base for equipment that would be difficult to accommodate on a conventional platform.
It also minimises the infrastructure required on land, particularly when it comes to the second phase of the project which will see the island linked to other nations via interconnectors.
Building infrastructure offshore also tackles a second problem faced by Belgium, Dunon explains. The country has just 60km of coastline and therefore has limited availability to bring multiple cables onshore. “You can basically with two cables have the same functionality that would have otherwise needed many more additional cables,” he adds.
The ongoing phase of the project will see the infrastructure put in place to connect the island to two wind farms in the vicinity. The second phase, still yet to be formally approved, will see a hybrid interconnector linked to the island, connecting a third wind farm and the planned Nautilus interconnector with the UK.
Dunon says the second phase of the project is vital to the island’s success: “This design is optimised in two ways, combining both offshore wind and interconnectors” he says. “It means when there is no wind, you can import electricity from the UK or export it, which is quite important for optimisation.
“It means you can use the [generation] assets nearly 100% of the time.”
Digital tools for an unmanned island
The island will house a small harbour and helipad so maintenance teams can reach the site when work is needed. Temporary accommodation is currently being installed on the island so workers can remain on site during the installation of the electrical equipment. However, once operational, the island will be unmanned.
Because the island will not be permanently staffed, digitalisation is central to its operation. The project depends on remote monitoring, automated control systems and digital models that help engineers understand how the island is performing without needing a continuous human presence offshore. An array of Internet of Things-powered sensors will send operational data back to the control room onshore, while a patrol of robotic dogs will walk around the high-voltage equipment and facilities, checking for problems and sending live images back to engineers on the mainland.
A digital twin has supported design and construction to model the island’s structure, simulating the effect of North Sea weather on the critical assets. Long before the installation of the island’s caissons, engineers simulated “1-in-100-year storm” scenarios. This modelling, carried out in partnership with DHI Group, calculated exactly how high and fast waves would break against the outer concrete walls, resulting in a specialised wave-deflecting wall design.
When the project enters its operational phase, the digital twin will ingest real-time telemetry from thousands of built-in-fibre-optic sensors, allowing engineers on the mainland to forecast infrastructure fatigue, schedule repairs, and prevent equipment downtime proactively.
For the electrical system, automated controls will balance flows of up to 3.5GW of wind power across the hybrid interconnectors. When high winds cause generation to suddenly surge or drop, automated grid stability controls will reroute the electricity through interconnectors accordingly, safeguarding the island’s conversion hardware from electrical overloads.
An array of sensors will also monitor transformers, switchgear, cable terminations and the island’s civil structure.
Dunon says that without these digital tools, the island would not have been feasible. He explains that the island will have to behave like an “intelligent grid node”, with mainland operators able to respond to conditions in near real time.
While many of the tools will ensure that the island is operating efficiently, digital tools are also being used to protect the island from physical threats – both natural (weather) and malicious actors.
As Dunon explains, military-grade radar equipment is integral to the island’s security. “It will be a strategic asset for Belgium, for Europe, and so you have to be sure you can protect it in the right way,” he says. “It is the same as if it was a nuclear power plant, we have to be able to monitor, to detect, and to be able to intervene when necessary.”
Despite being a true world-first, Dunon says that being innovative was never a driver behind the project: “We always say it is an innovative project; that is the first of its kind in the world. But honestly, I don’t care. It is just the most optimal and most cost-effective solution. By accident, it’s also a world first.”
Cost and supply chain pressures
Several challenges have been overcome to reach this point. The development of the island perfectly illustrates the strain facing offshore grid supply chains. Demand for HVDC systems, transformers, cable capacity and specialist electrical equipment has risen sharply across Europe and has forced Elia to change its approach to keep costs down.
Dunon explains that a lot has changed since initial plans were drawn up. “Due to geopolitical evolution, due to acceleration of the transition, due to the unprecedented demand in HVDC technology, we had to look again at the design to see where we could make some modifications to the project.
“We streamlined the design and we came up with some adaptations to the project without changing the objectives.”
The design optimisation was carried out after the Belgian Government initially rejected the company’s plans for the second phase of the project. While an official cost for that phase has not been made public, the first phase is reported to cost €3.6 billion (£3 billion) and estimates suggest that the total project cost for both phases could range between €7 billion and €9 billion (£5.9 billion to £7.5 billion).
Cost of the first phase of the project
Estimated final cost of both phases of the project
Amount of credit from the European Investment Bank
Elia has since drawn up a lighter version for the second phase of the Princess Elisabeth project. The revised plan slightly reduces capacity and cuts the number of cables to be installed. According to Dunon, changes to design could lower the cost of the direct-current infrastructure by €2 billion (£1.7 billion) largely by reducing the number of cables that need to be installed.
Despite political decisions still to be taken, momentum on the project has not stalled and Elia has secured major European Investment Bank (EIB) support, including a €650 million (£545 million) green credit line for the first phase and a further €1 billion (£840 million) facility for the next phase of electrical infrastructure – making it the EIB’s largest investment in a single energy project to date.
The latest funding covers elements such as high-voltage substations, switching stations, transformers and AC connections to the Belgian mainland. The terms of the financing are intended to reduce overall costs and limit the impact on consumers, but the project remains a large upfront investment which is ultimately passed down to customers via transmission charges on energy bills.
The economic argument largely rests on the counterfactual of doing nothing and remaining open to fossil fuel market shocks, Dunon adds: “There has been a lot said about the costs of the island during the last two or three years. And that is a fair question to ask. But the real question is not what it costs, but what it enables.
“Not investing in the grid would have consequences. Look at the Netherlands and the UK where there is congestion and also here in Belgium. Not doing this project would create more congestion, which would increase reliance on fossil fuels which then has consequences on the [consumer] bill. The business case is positive for Europe, for Belgium and for our colleagues in the UK.”
For the EIB, investing in the energy grid is a direct investment in the energy transition. EIB vice president Robert De Groot says that “the good news is that funding for the energy transition is not the main constraint today”.
“What we increasingly need is to accelerate the pipeline of bankable projects and create the right conditions to deploy capital at scale,” he adds. “A modern and resilient grid is a key component not only of Europe’s energy security, but also of its competitiveness. […] Connecting more offshore wind power and expanding the capacity of the grid will help to create a more stable market. This needs large investments, and we’re happy to support Elia in taking a leading role in making this happen.”
The Mayor of Ostend John Crombez also plays down the costs of the project, likening it to conversations which were had at the turn of the century related to offshore wind generation: “We had the same debate on cost 25 years ago on offshore wind as we have had with this energy island. That will eventually stop.”
“What we increasingly need is to accelerate the pipeline of bankable projects and create the right conditions to deploy capital at scale.”
Robert De Groot, vice president, European Investment Bank
A blueprint for future connections?
Artificial islands will not be the answer for every offshore wind zone. But the principle of connecting countries together via offshore grids made up of hybrid interconnectors and energy hubs is likely to spread.
De Groot says that the EIB expects the Princess Elisabeth Energy Island to be the first in a series of energy islands. Meanwhile, Jan de Nul head of commercial offshore cables Filip Olde Bijvank reveals that his company has already been approached by other clients around the world to build similar projects.
National Grid, in the UK, is keen to see approval for the second phase of the project to connect the Nautilus link with the island. National Grid Ventures president Rebecca Sedler tells GridEx the energy island is just one example of grid infrastructure moving offshore. She points to other projects in the UK, Denmark and Germany as examples of where infrastructure traditionally installed onshore is being taken out to sea.
“I think that’s going to happen more and more,” Sedler says. “It won’t always be in the form of an energy island but offshore grids for sure will continue to grow.”
