Six intercontinental power links that want to reshape the world of energy

“Interconnectors are as vital to electric grids as motorways are to road transport networks and will be essential for countries to decarbonise their energy system while maintaining energy security,” said Ben Hertz-Shargel, global head of grid edge at energy consultancy Wood Mackenzie.

Interconnectors can also help make renewable energy projects cheaper, he said. A wind or solar farm can be built where it is windiest or sunniest, rather than in a less suitable location where power demand happens to be greatest.

They can also be built in countries with cheap and abundant land, rather than trying to squeeze them into more densely populated areas – all of which ultimately helps cut bills for consumers.

Sometimes an interconnector will be a one-way flow from a country with the potential to generate abundant and cheap renewable energy. On other occasions, electricity will flow both ways at different times of day, matching a peak in power generation in one time zone with a peak in power demand in another.

The world’s longest power link to date over land and sea is the Viking Link between Denmark and the UK, a £1.7bn ($2.2bn) project that stretches 764km.

One of the masterminds behind Viking Link is Rebecca Sedler, the managing director for interconnectors at National Grid in the UK. She said there has been continuous growth in interconnectors as the world brings more renewables online and, in Europe, countries cut their dependence on Russian gas following the invasion of Ukraine.

The “enormous amount of flexibility” that interconnectors bring to power systems helps countries decarbonise quicker and become less “vulnerable to price volatility driven by international gas markets,” she said.

Failure to have enough interconnectors can be devastating, and even deadly, said Hertz-Shargel.

Texas is a “cautionary tale”. The US state avoided building interconnectors to Eastern and Western US power grids to avoid federal regulation. But the folly of this was made clear in 2021, when a winter storm knocked out much of the state’s generating capacity.

Unable to import power from other regions, Texans were left trapped in the dark and freezing cold. Nearly 250 people died, according to the state. Other estimates have put the death toll much higher.

While numerous interconnectors are now online, particularly between European countries, the next generation of power links is set to be far more ambitious – sharing electricity not just between countries and regionally, but between continents, as is the case for the projects listed below, many of which will not come online for at least a decade.

Morocco-UK interconnector – 4,000km

A plan by UK start-up Xlinks to pump Saharan wind and solar power from the Moroccan desert to the UK has hit the headlines repeatedly in the last year as it picks up a string of high-profile backers.

Xlinks wants to build wind and solar facilities capable of generating 11.5GW of power in Morocco, connecting this to the UK via a 4,000km subsea cable that will snake around Europe’s Atlantic coast.

Xlinks claims the link can deliver green power to seven million British homes, meeting 8% of the country’s energy needs. Crucially the link would be able to deliver reliable energy magnate demand for an average of over 19 hours a day, it is claimed, smoothing out ups and downs in wind and solar generation in the UK.

Australia-Singapore interconnector – 5,100km

The longest interconnector project on this list, and possibly in the world, is a proposed A$30bn ($20bn) plan by project company Sun Cable to build a 5,100km power link running from the Australian outback to Singapore.

Green power generated would first travel 800km overland to Darwin, where 3.9GW of it would be used, before a not inconsiderable 1.75GW would travel 4,300km further through a subsea cable to Singapore.

Singapore is perhaps the perfect example of a country crying out for interconnectors such as this. Around 6 million people are crammed into the city-state, where land is at an absolute premium, making building onshore renewables difficult.

Europe-North America interconnector – 3,500km

Perhaps the most ambitious and complex interconnector plan of them all, and certainly the one at the earliest stage, is the aforementioned plan to link the power grids of Europe and North America.

The three entrepreneurs behind the project want to create a 6GW interconnector linking the two continents. They plan for it to branch out at either side, with three landing points in North America and another three Western Europe.

While the link's layout is yet to be decided, it would likely connect Newfoundland in Canada with the UK and Ireland. The link is envisaged at around 3,500km, although given the current uncertainties, this is with a margin of error of around 500km either way.

The project would cost an estimated $28-40bn using 2023 prices.

Azerbaijan-EU interconnector – 1,200km

Russia’s invasion of Ukraine and the resulting energy crisis completely reshaped European thinking on energy policy.

Recently re-elected European Commission president Ursula von der Leyen said that a proposed 1,200km cable beneath the Caspian and Black Seas could help the bloc “turn its back” on Russian gas, replacing it with green power from Azerbaijan.

The proposed 1GW link would run from Azerbaijan, which straddles Europe and Asia, through Georgia, Romania and onto Hungary. Some power could also be diverted to Ukraine, whose power generation facilities have been decimated by Russian missiles.

The Black Sea is seen as a potential major source of future offshore wind power, with projects mooted off Romania and Turkey.

Azerbaijan is a petrostate that relies almost entirely on fossil fuels for its own energy needs, but the upcoming COP29 host is now making increased efforts to build up its renewables capacity.

Greece-Egypt interconnector – 1,000km

Another North African country with plans to export green power to Europe is Egypt.

This interconnector plan envisages using a 1,000km subsea cable to link Greece with Egypt (with the initials of those two countries giving the project its name, ‘GREGY’).

The project is being led by Greece's Copelouzos Group and Infinity Power, a joint venture between Masdar and Egypt’s Infinity.

Copelouzos has said the link would carry 3GW of power from a massive 9.5GW array of renewable energy sources that the project partners would build and operate in Egypt.

The power sent to Europe will be evenly split between use for Greek homes and industries, export to neighbouring countries, and use in Greece to produce green hydrogen for export in the EU.

Much like the Azerbaijan-EU link, the GREGY interconnector would help the EU wean itself off Russian gas, as well as meet its net zero targets.

The European Commission describes the interconnector as a “flagship project”.

Saudi Arabia-India interconnector – length unknown

A proposed power link between Saudi Arabia and India could reshape the countries' relationship.

India has long been a large buyer of Saudi oil and gas but an interconnector would transform this into a two-way partnership between the countries.

A memorandum of understanding signed by the two countries last year said they will cooperate on connecting their grids, as well as collaborating on renewables more generally.

India’s then-energy minister was quoted in Arab News as saying that the interconnector would be a "game changer," bringing down the cost of electricity for the whole region.

Indeed, the overarching goal of connecting global energy grids has perhaps been articulated best by India's Prime Minister, Narendra Modi, who in 2018.

Modi's mega-plan aims to as a first step connect the power grids of India, the Middle East and South East Asia, before incorporating Africa and then, finally, achieving true global green power harmony with the aim of a staggering 2,600TW of interconnection around the world by 2050.

Ultimately, as Modi put it, the aim is delivering "One Sun, One World, One Grid."