GE Vernova and Seatrium have been awarded a contract by transmission system operator TenneT to deliver a major part of BalWin5, a 2.2-gigawatt (GW) offshore high-voltage direct current (HVDC) grid connection intended to link offshore wind farms in the German North Sea with Germany’s onshore transmission network.
BalWin5 is part of TenneT’s new generation of 2 GW offshore grid connection projects, which are designed to increase the volume of offshore wind power integrated into the German electricity system. Once operational, the connection is expected to supply renewable electricity equivalent to the needs of around 2.75 million households.
The award marks the fourth project secured by the GE Vernova–Seatrium consortium under a five-year Framework Cooperation Agreement with TenneT signed in March 2023, and its first contract related to TenneT’s German 2 GW projects.
Under the contract, GE Vernova’s Electrification Systems business will supply the onshore and offshore converter stations and the full HVDC technology package, including control and protection systems intended to ensure stable transmission network operations. Seatrium will be responsible for the design and construction of the offshore converter platform, as well as transportation and installation in the German North Sea. Fabrication is scheduled to begin on 1 January 2026, with most of the platform construction taking place at Seatrium’s facilities in Singapore and Batam.
“BalWin5 reflects the scale and ambition of Germany’s energy transition, and we are proud to support TenneT in this important programme,” said Philippe Piron, CEO of GE Vernova’s Electrification Systems business. “Our Electrification Systems business brings decades of innovation in HVDC technology, helping deliver solutions that are designed for efficiency, affordability, and long-term energy security. Working alongside Seatrium, we are confident in our ability to deliver a high-quality system that strengthens the offshore grid and supports Europe’s move toward a more resilient and sustainable electricity infrastructure.”
Samuel Wong, Executive Vice President of Seatrium Energy (Fixed Platforms), said: “We are proud to extend our partnership with TenneT and GE Vernova to deliver this offshore wind solution. Leveraging the design and experience gained from the first three platforms we are building for TenneT, we are confident in delivering a high-quality product through our series-build strategy, underpinned by our One Seatrium Global Delivery Model.”
BalWin5 is part of TenneT’s wider BalWin programme, which aims to transport large volumes of electricity generated by offshore wind farms in the German North Sea to the onshore grid. The BalWin5 system is being designed to transmit up to 2.2 GW of power, exceeding the standard 2 GW capacity by incorporating technical headroom that allows additional electricity to be carried when wind conditions permit.
The project will include an offshore converter station in the North Sea, an onshore converter station at Bremen-Werderland, and approximately 325 kilometres of combined offshore and onshore cabling. Commissioning is currently planned for 2032.
According to TenneT, increasing the capacity of offshore grid connections from around 900 megawatts to more than 2 GW enables more efficient use of infrastructure and reduces the cost per megawatt of transmitting offshore wind power. The company is applying this standard across multiple projects through long-term framework agreements aimed at improving delivery timelines and cost efficiency.
