Construction of Formosa 4 Offshore Substation Starts in Vietnam

The consortium between Semco Maritime and PTSC Mechanical & Construction has cut the first steel for the Formosa 4 offshore substation (OSS) at PTSC M&C’s fabrication yard in Vung Tau, Vietnam.

Under a contract awarded in late August 2025, the consortium is responsible for the design, procurement, construction, and commissioning of the offshore substation’s jacket and topside, with scheduled delivery by the end of 2027.

Semco Maritime is leading the engineering, procurement, and commissioning of the main MV/HV electrical systems and auxiliary platform systems, supported by ISC Consulting Engineers. PTSC M&C is responsible for the jacket engineering, procurement, and construction (EPC) scope, procurement of remaining topside equipment and materials, as well as fabrication of the topside at its Ho Chi Minh yard.

Formosa 4 is the consortium’s third offshore substation project in Taiwan, following the delivery of the Hai Long OSS and the Feng Miao OSS, on which the consortium is currently working.

The offshore substation will be transported and installed at the Formosa 4 site by DEME.

Synera Renewable Energy’s Formosa 4 will be built approximately 20 kilometres off the coast of Miaoli County and will comprise 35 Siemens Gamesa 14 MW wind turbines. 

In December, SRE said that it had sold the entire output of the 495 MW offshore wind farm, having signed three corporate power purchase agreements (CPPAs) for the project.