Harland and Wolff has secured a major new contract it says will support 200 jobs.
The east Belfast facility has been tasked with making 24 huge steel foundation jackets for an offshore wind farm company.
The project is due to begin early next year and will last for about 18 months.
Standing at 65 metres tall, and weighing more than 845 tonnes, the three-legged steel jacket structures are expected to be almost as prominent on the Belfast skyline as the famous Samson and Goliath cranes.
United Arab Emirates-based Lamprell, an international provider of fabrication, engineering and contracting services, will also work on the contract.
H&W chief executive Robert J Cooper said: "H&W is delighted to work with such a prestigious company as ScottishPower Renewables on a project of nationally significant importance."
Jonathan Guest, H&W director, business development said: "In a global supply chain environment, it is significant when a developer stands over its commitment to give opportunities to local fabricators as demonstrated by ScottishPower Renewables in the East Anglia One project.
"Given the opportunity of a level playing field, UK fabricators can surpass the best the market can offer.
"When you consider the importance of this project to the UK with regard to energy security, that is not only green but at a low cost, you can understand the pride Harland and Wolff have in being part of this important development."
The ScottishPower Renewables North Sea project, known as East Anglia One, is a £2.5 billion offshore wind farm expected to generate 714MW of electricity when completed in 2020, enough to power 500,000 homes per year.
Chief executive Keith Anderson said: "We are pleased that Belfast will play important roles in delivering this project, supporting hundreds of skilled jobs.
"The facilities in Belfast are excellent for supporting offshore wind construction, as we experienced on our West of Duddon Sands project.
"We hope that the successful delivery of this contract will lead to even more opportunities in the offshore wind industry for Belfast."