Works at full speed at New York’s 1.25 GW subsea HVDC link

DeepOcean has completed its first campaign under a contract with NKT for the provision of subsea construction support for a subsea HVDC cable that will link the Canadian border and New York.

DeepOcean reported that its U.S. operation had wrapped up the first campaign for the Champlain Hudson Power Express (CHPE) renewable energy infrastructure project in New York.

The CHPE project will transmit power from the Canadian border to Queens, New York, through a 339-mile-long (around 545 kilometers) subsea HVDC cable, providing renewable power to more than one million homes in New York. Construction on the project kicked off on November 30, 2022.

DeepOcean’s scope of work includes project management, installation engineering and installation of subsea mattresses along the Hudson River in New York. The mattresses will be installed during three different campaigns over a two-year period. The first installation campaign was completed this April.

A U.S.-flagged vessel with U.S. personnel installing locally sourced concrete mattresses was engaged for the work.

NKT won the contract for the engineering, manufacturing and installation of the high-voltage 400 kV DC transmission line in the summer of 2022.

“We believe that being chosen to support NKT on this project is a recognition of our technology and innovative approaches in the subsea space,” said Tony Stokes, President of DeepOcean’s U.S. operation.

“For example, we will for this project apply a newly developed intelligent mattress frame which basically transforms a standard mattress frame into a fully independent ROV system that can deploy up to four mattresses in a single dive. This reduces both installation time and cost.”

The CHPE link will contribute to New York’s Climate Leadership and Community Protection Act (CLCPA), which aims for the state to be powered by 70% renewable energy by 2030 and is expected to decrease CO2 emissions by an average of 3.9 million metric tons per year, equivalent to removing 44% of passenger vehicles from New York City.

CHPE will transfer up to 1,250 MW of electricity, enough to power 1 million New York households, for more than 600 kilometers underground from Hertel, Canada, through Lake Champlain and the Hudson River, to an HVDC converter station in Astoria, Queens.

Hitachi Energy is the supplier of the HVDC converter station with Light technology, while the lead contractor for the site is Kiewit Corporation.

Construction on the converter station officially began on June 22, 2023, including remediation work that was required to prepare the site for construction. In total, six tanks which previously stored 12 million gallons of No. 6 oil, as well as nearly four miles of piping were removed from the site.

The complete CHPE system, of which the HVDC converter stations are the enabling technology, is expected to create more than 1,400 jobs during construction and, during the first 30 years of operation, deliver almost $50 billion in economic benefits to New York state. Construction is expected to be completed in 2026.