Neptune Regional Transmission System, LLC is the company that developed and built the 65 mile electric transmission line from Sayreville, New Jersey to Nassau County on Long Island via undersea and underground cable. Because Long Island's rapidly growing electricity consumption outpaces its ability to build new, economical "on-island" generation, the Neptune cable is seen as an environmentally friendly, cost-effective solution to future power needs.

A consortium of two leading global companies, Siemens Power Transmission and Distribution, Inc. and Prysmian Cables and Systems USA, LLC provided the engineering, procurement, and construction services for manufacturing and installation of the cable and construction of the converter stations and installation of station components.

This cable provides 660 MW of electrical capacity -- enough to provide power for 600,000 homes.  The cable allows the Long Island Power Authority (LIPA) (www.lipower.org) to purchase power from one of the most diverse and competitively-priced power markets in the United States. This market, called "PJM" (www.pjm.org), controls electricity flows in all or parts of Delaware, Illinois, Indiana, Kentucky, Maryland, Michigan, New Jersey, North Carolina, Ohio, Pennsylvania, Tennessee, Virginia, West Virginia and the District of Columbia. This region contains more than 100,000 MW of diversified and relatively low-cost power generation.

In short, LIPA can purchase power over the Neptune cable for less than new energy assets can be built from scratch on Long Island.

“Long Island enters a new era with the Neptune cable,” said LIPA Chairman Kevin Law. “The Neptune cable provides LIPA with the opportunity to acquire lower-cost energy to meet customer needs while providing more flexibility in selecting the markets from which we acquire that energy. It is a significant win-win for Long Island.”    

“The Neptune cable project will provide Long Island with the opportunity to significantly diversify its energy resource options,” said former LIPA Chairman Richard M. Kessel. “LIPA will be able to tap the Pennsylvania, Maryland and New Jersey (PJM) power markets directly for the first time, and help LIPA acquire power that is priced very competitively, because of the diversity of generation resources in that area. The Neptune cable will make Long Island less isolated and more secure by providing access to a wider selection of mainland power supplies,” said Mr. Kessel. “For the first time ever, LIPA will be part of an eastern seaboard energy corridor, with power flowing up and down the East Coast.” (Source: 9/29/04 LIPA Press Release)

What Problem Will Neptune RTS Solve?

To avoid energy shortages and supply disruptions, the Atlantic seaboard needs new sources of power generation. Yet as the Blackout of 2003 proved, it also needs expanded transmission networks, especially to serve "load growth" in areas constrained by available land (such as Long Island). Air quality requirements, the price of land, and opposition to the construction of power plants and overhead transmission lines stymie the development of new energy sources to meet the demands of these areas. These constraints are a recipe for higher consumer prices and the risk of rolling blackouts during hot summer days.

The Neptune cable allows LIPA to tap into a diverse range of power generation including hydroelectric, biomass, oil, coal, nuclear and natural gas.  This diversity of generation sources is not available on Long Island.

HVDC Technology

Neptune RTS deploys state-of-the-art HVDC technology, which has been used in scores of applications worldwide for many decades.  HVDC has long been the preferred technology for moving bulk power over long distances. 

Since 1977, Siemens AG (www.siemens.com) has designed and built over 20 HVDC projects throughout the world.  Siemens Power Transmission and Distribution, Inc., a wholly owned United States subsidiary of Siemens AG, supplied the HVDC conversion and control technology for the Project. 

Prysmian Cables and Systems (formerly Pirelli Cavi y Systemi Energia SpA, www.prysmian.com) supplied a mass impregnated (MI) 500 kV HVDC submarine cable as the main link that connects Long Island to the PJM grid in New Jersey.

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