Work will start in July on the firm’s 90-acre site that sits alongside the under-development South Bank Quay.
It will create 750 direct jobs and 1,500 more in the supply chain and during construction.
Originally SeAH planned to build the factory at the Able Marine Energy Park on the Humber Estuary. It said that due to “business reasons” it has been unable to finalise an agreement for Humberside.
The large monopile steel tubes will form the foundations for wind turbines destined to create the world’s largest offshore wind farm at Dogger Bank.
When fully operational in 2026, it is expected to be able to produce between 100 and 150 monopiles per year.
It will be built on the 4.5m sq ft offshore wind and industrial space being created on 450 acres of land next to the wharf and heavy-lift South Bank Quay.
The first phase of the quay was recently awarded £107m of funding in the UK Infrastructure Bank’s first ever investment.
Piling to strengthen the quay wall is now taking place, with the full phase one 450m quay due to be complete by March 2023.
Tees Valley Mayor Ben Houchen said: “2022 is our year of construction and this is another transformational project that places Teesside as the UK lead for clean, green manufacturing.
“Spades will be in the ground for this factory at the beginning of July.
“We’re wasting no time in clearing land and developing schemes like the South Bank Quay, which has proved a massive draw to SeAH as it is for other businesses in the offshore sector.