Cross-border electrical interconnections: the backbone of Europe

Cross-border electrical interconnections form a key part of security, market efficiency and the transition to a sustainable energy supply system in Europe.

Europe is undergoing a radical energy transformation, dictated by climate urgency, geopolitical factors and the strategic objective of reducing dependency on imported fossil fuels.

In that context, these infrastructures emerge as key elements in ensuring that supplies are protected, while favouring the introduction of renewable energy sources and completing the creation of one single energy market.

What are cross-border electrical interconnections and why are they so important?

The term cross-border electrical interconnection refers to a physical connection between the electricity grids of two or more countries, enabling a two-way flow of electricity between them.

They can be designed to use either alternated current (AC) or high voltage direct current (HVDC).  The latter is preferred for long distances or underwater connections, thanks to its efficiency in reducing power failures.

These international ‘links’ are essential to:

• ensure energy security: in case of a crisis or peak in demand, they allow electricity to be imported or exported, balancing flows;
• addition of renewable sources: electricity from photovoltaic or wind power (often produced in excess at certain times or in particular areas), can be transferred to areas experiencing a deficit, maximising use;
• create a florid market: they enable greater competition between producers, leading to more uniform prices and better system efficiency;
• stabilise the European electricity network: thanks to a constant flow between countries, blackouts and network imbalances can be avoided.

The way they operate is fairly simple and involves incorporating these interconnections into high voltage transmission systems. When two electricity systems are synchronised (as in most of continental Europe), the most natural solution is an AC interconnection.

In the case of asynchronous systems, such as the British and continental European networks, HVDC cables are used, with AC/DC/AC converters at their end points.

Each interconnection is managed via capacity contracts, allocation auctions and balancing markets.  The transmission system operators (TSOs) work together to define optimal flow in real time, minimising costs and guaranteeing security.

Principal European projects and Italy’s role

Europe has set itself the target of reaching a level of electrical interconnection of 15% by 2030.  That means that every member state should be able to export at least 15% of its own installed capacity to other countries.

The most strategic projects are:

• Italy-Slovenia (East-West Transmission): strengthens the integration of southeast Europe;
• Italy-Austria (Resia): currently under construction, it will considerably increase available capacity between the two countries;
• NordLink (Germany-Norway) and Viking Link (UK-Denmark): two examples of HVDC conections, which connect systems featuring extensive use of hydoelectric energy or offshore wind farms;
• France-Spain Interconnectors (Baixas-Santa Llogoaia) and future underwater connections across the Pyrenees.

Italy is in a stregic geographical position, acting as a bridge between continental Europe and the Meditteranean.  It is investing heaviy in new infrastructures in order to become a European energy hub.  The Terna company, an Italian TSO, is working on around ten new or enhanced interconnections, including:

• Tunisia-Italy interconnection (Elmed): an underwater cable will carry solar power produced in North Africa;
• Italy-France (Piemonte-Savoia): already operational, it crosses the Alps and uses advanced, low impedance technology;
• Italy-Montenegro: builds resilience in western Balkan states.

Challenges to be faced and the tools available to Europe

In order to establish cross-border electrical interconnections,  several challenges must be overcome.  The most significant of these are the considerable length of time required to obtain authorisations and the complex bureaucracy involved.  (It can in fact take as long as ten years to complete such an infrastructure, due to complicated procedures and local opposition).

Another factor to consider is acceptance by the local community, who are often reluctant when the planned route for the project passes through protected or densely populated areas, due to its impact on the environment and landscape.

As for the financial aspect, the costs involved are very high, with investment in each project potentially reaching billions of euros.  These costs are often sustained jointly by public sector operators, network managers and European funding.

In conclusion, the growing use of digital, smart technologies improves efficiency on the one hand, but on the other, exposes networks to increased risks mainly associated with IT security.

The EU is aware of the issues described above and has introduced several schemes to support interconnections and facilitate their construction.  The most interesting are listed below:

• TEN-E (trans European networks for energy): selects Projects of Common Interest which will benefit from accelerated procedures and European funding;
• Connecting Europe Facility (CEF): a fund for the development of trans border infrastructures;
• Regulation of Electricity Market: promotes cross border cooperation and efficient capacity allocation.

The coordination of national transmission operators is handled by ENTSO-E, a European agency which plans for future energy scenarios, simulates network reliability and develops ten year network investment plans (TYNDP).  Each interconnection is inserted into a shared architecture, in order to avoid duplication and ensure maximum efficiency.

Interconnections, European Green Deal and future developments

It is interesting to observe that trans border electrical interconnections play a central role in the European Green Deal.  In order to achieve climate neutrality by 2050, many sectors, including transport and manufacturing, will need to undergo electrification, while the quota of green electricity used will have to be signfiicantly increased.  This means that a flexible European electricity network, which is both connected and smart, will be even more essential.

The integration of smart, digital networks will play a crucial role, as in this configuration, interconnections will transport not only electricity but data too.  Artificial intelligence algorithms, sensors and predictive systems will enable flows to be optimised, by forecasting peaks in demand and connecting millions of prosumers.

It is clear from the points mentioned above that cooperation will be essential if the project to succeed.  Only shared governance between member states will ensure a European network that is resilient, fair and focused on sustainability.

Translated by Joanne Beckwith