Offshore wind turbines are popping up all over the world and with good reason. The winds over the ocean tend to be stronger and more constant than those on land. There are also fewer NIMBY concerns from folks who dislike the sight of whirling turbine blades in the background as they tend their petunias. But getting the electricity generated by offshore wind projects to where it is needed can be a challenge.
This week, three of the UK’s biggest energy companies announced they will construct a massive undersea high voltage direct current “superhighway” from Peterhead and Torness in Scotland to Selby and Hawthorne Point in northern England. The so-called Eastern Link will carry up to 2 GW of electricity via some of the longest high voltage undersea cables in the world. That’s enough to keep tea kettles boiling in 4.5 million British homes. It will create hundreds of jobs during the construction phase and will cost several billion pounds.
Construction is slated to begin in 2024 and the project could be expanded to carry up to 4 GW of electricity in the future. The east coast of Scotland is already home to about 1 GW of offshore wind turbines and has another 4.4 GW of new offshore wind projects pending. After the next leasing round for offshore wind licence areas, there could be up to 10 GW in Scottish waters in the coming years according to The Guardian.
The participants in the Eastern Link partnership are Scottish Power, National Grid, and SSE. Scottish Power and National Grid are already working together on the Western Link that will interconnect wind turbines along the west coast of Scotland and near Wales with England. That project, however, is behind schedule, leading to an investigation by regulators. The Eastern Link news was timed to coincide with the announcement that the UK will host the COP 26 climate conference in Glasgow in 2021.
The UK has a goal of powering every home in the country with electricity generated by offshore wind turbines by 2030. In total, the government hopes to build 40 GW of offshore wind power capacity in UK waters within the next decade as part of its plat to build a carbon neutral economy by 2050.
Nicola Shaw, National Grid’s UK executive director, says the new project “will become part of the backbone of the UK’s energy system. It’s a great example of companies working together on impressive engineering feats that will help the country hit its net zero carbon target by 2050.” Keith Anderson, CEO of Scottish Power adds he believes the UK can achieve its net zero target, “but it must be done through investment and innovation in essential projects like the Eastern Link, providing benefits for customers and society in the long term”.
Alistair Phillips-Davies, the chief executive of SSE, described the project as “one of the most exciting energy developments over recent decades.” He termed it as “essential to delivering the UK’s 40GW offshore wind target by 2030. With the eyes on the UK ahead of COP 26 next year, this project clearly demonstrates how the UK is leading the world in tackling the climate emergency and supporting thousands of jobs and supply chain opportunities,” he said.
Placing HVDC transmission lines under the ocean avoids many of the siting and permitting issues often associated with land based systems but comes with special risk factors. We know more about the back side of the moon than we do the ocean floor. Not only is laying undersea cables fraught with technical challenges, fixing things that go wrong after the cable is installed is often difficult and expensive.
While the Eastern Link may be one of the longest undersea power cables once it is built, there are plans to create a 3,800 kilometer long transmission line from Western Australia to Singapore. If it ever gets built, it will make the Eastern Link look like child’s play by comparison.
David Griffin, who heads the Sun Cable initiative, told The Guardian last year undersea transmission cables are “greatest unsung technology development. It is extraordinary technology that is going to change the flow of energy between countries. It is going to have profound implications, and the extent of those implications hasn’t been widely identified.”
Griffin adds, “If you have the transmission of electricity over very large distances between countries, then the flow of energy changes from liquid fuels — oil and LNG — to electrons. Ultimately, that’s a vastly more efficient way to transport energy. The incumbents just won’t be able to compete.” Clearly the Eastern Link is just the tip of the iceberg when it comes to the role undersea transmission cables may play in the world’s energy future.