Undersea transmission project connects Long Island with New Jersey and saves millions of dollars (16/10/2007)
The Neptune Regional Transmission Project, the largest underwater HVDC (High Voltage Direct Current) system in the United States, gives Long Island Power Authority (LIPA) and its 1.1 million customers access to 660 MW of reliable electricity from the 13 State PJM energy grid.
After LIPA completed a competitive RFP process in 2004, Neptune began construction of two converter stations and the 65-mile cable in July 2005. The approximately $600 million transmission system commenced operations in June, ahead of schedule and within budget.
The 65-mile undersea and underground transmission link connecting Long Island with New Jersey saved LIPA an estimated $20 million this summer during the first 100 days of operation. The Neptune Regional Transmission Project is expected to result in more than $1 billion in net benefits over 20 years to LIPA and its customers.
More than 50 miles of the cable are buried beneath the Raritan River, New York Harbor, and the Atlantic Ocean, transmitting power from Sayreville, New Jersey to Long Island, where it comes aground near Jones Beach.
“The Neptune Project is an example of how this type of HVDC technology can bring much–needed electric power and transmission infrastructure to densely populated areas in a cost–effective and environmentally friendly way,” said Edward M. Stern, Neptune’s President and Chief Executive Officer. “Many American cities that face growing demand for energy would be well served by implementing projects such as Neptune – and more renewable energy projects would be built to serve such demand.”
“This historic power project has given Long Island direct access to a lower cost, more diversified power supply in the PJM power market that stretches from New Jersey to Illinois,” said LIPA CEO and President Kevin Law. “The money saved this summer is significant and in the long term will help us meet our objective of holding down the power supply charges as much as possible.”
“Of all of the new power supply resources that have been added to LIPA’s portfolio in recent years this is the most important,” said Mr. Law. “It provides Long Island with a more economic and more diverse energy supply that will help reduce our dependence on foreign oil over time. We’re extremely pleased that it is operating well and producing the kinds of economic benefits for Long Island we anticipated.”
The Neptune cable is the first 500kV submarine cable links using mass impregnated, paper insulated technology that has virtually no impact in case of external damage. Also, the installation was performed using equipment owned and/or engineered by Prysmian with minimum environmental impact.
“We are very proud of the Neptune project,” said Hans Nieman, Prysmian Director of High Voltage and Submarine Systems. “This project, the first 500 kV submarine cable connection ever realized using environmentally friendly mass impregnated paper cable, further confirms Prysmian’s worldwide expertise in the submarine cable sector. Prysmian utilized a state-of-the-art technology, which enabled the project to be completed successfully ahead of time and in accordance with the local ecological guidelines. The cable was in fact laid out in an environmentally sound manner, avoiding major fisheries and other ecologically sensitive locations.”
A converter station in New Jersey transforms alternating current (AC) power into direct current (DC) power for transmission to Long Island, while the Long Island converter station transforms DC power back into AC power for distribution to customers. The power can move in both directions.
“As urban areas worldwide face critical power shortages, LIPA and other utilities recognize that HVDC technology is technically advantageous over traditional AC methods for accessing the grid, connecting to renewable energy sources and strengthening grid reliability,” said Dave Pacyna, president and CEO of Siemens Power Transmission & Distribution, Inc. “Siemens is recognized around the globe as the leader in providing HVDC technology solutions for efficient, secure and reliable grids.”
Neptune Regional Transmission System, LLC (Neptune RTS) is the developer, owner and operator of the Neptune Project, responsible for its planning, permitting, financing and construction. Affiliates of Energy Investors Funds and Starwood Energy Group are the principal equity investors in Neptune RTS.
Siemens Power Transmission & Distribution, Inc., provided the design, engineering, construction and installation of the HVDC converter stations in Sayreville, NJ, and New Cassel, N.Y. Siemens will also provide operation and maintenance services for the first five years of the project’s operation. Prysmian Cables and Systems USA, LLC manufactured and installed the 65 miles of 500 kV undersea and underground cable that connects the two converter stations.