NEW YORK, NY- Add another one to the over hundred high voltage direct current (HVDC) transmission systems worldwide transmitting 55 gigawatts. Siemens Power Transmission and Distribution turnkeyed the 660 megawatt Neptune Project connecting the Long Island Power Authority to PJM’s New Jersey grid by linking 65 miles of Prysmian Sea and Land Cables.
Dave Pacyna, President and CEO of Siemens PTD, speaking at the dedication ceremony said: “Siemens is proud that our technology played a major role in bringing the Neptune Project to reality.” Siemens commissioned Neptune ahead of schedule, under budget and is providing operations and maintenance services for the first five years, Neptune’s Ed Stern told the 375 invited guests at the ceremony.
Neptune Regional Transmission System developed the $600 million project over five years after LIPA issued a 20-year Firm Transmission Capacity Agreement as part of its long-term goal to deliver 1,000 new megawatts by 2010. Funding was provided by Energy Investors Funds and Starwood Energy Investors.
Neptune awarded a consortium of Siemens and Prysmian the contract to design and build the project in July 2005. As consortium manager, Siemens PTD designed, manufactured and installed the HVDC equipment. Siemens also constructed the 30,000 square foot converter stations consisting of valve and control buildings and an outdoor bank of electrical conversion equipment.
The PJM converter station located in Sayreville, NJ transforms AC power into DC power for transmission to the Duffy Avenue Converter Station in Hicksville, Long Island where it is converted back into AC power for distribution to LIPA’s grid. The Neptune system is bi-directional so needed power could be switched back to PJM.
PJM is the largest U.S. electricity wholesale market totaling 165,000 megawatts of capacity generated from nuclear, renewables, coal and gas.
The Siemens HVDC Control System can regulate the flow, level and direction of power in milliseconds. HVDC Systems help stabilize the networks and restrict the extent of line disturbances. Siemens continues to test the latest HVDC Systems in its Erlangen, Germany Simulation Center. After the test phase, the equipment is packed and set up on site by the same team of engineers who performed the “functional performance test.”
Before cable construction started, applications were filed. A Waterfront Development Permit was issued by the State of New Jersey in 2003; a Certificate of Environmental Compatibility from the New York Public Service Commission came through in January 2004; the U.S. Army Corps of Engineers signed off in February 2005 and the New York State Department of Transportation cleared the way for cable installation in October 2005.
Prysmian Cables and Systems USA manufactured and installed the 65 miles of 500kV undersea and 345kV underground cable connecting the two converter stations. The 9-inch encased bundle of three cables traveled 51 miles under the Atlantic Ocean, crossing Raritan Bay and the New York Harbor and surfaced alongside the Wantagh Highway near Jones Beach for the 14-mile land link.
Prysmian installed Neptune in two successive operations; the first by using a laying barge and the second using the cable ship “Guilio Verne” to respect the environmental conditions and avoid major fishery locations. Guilio Verne is capable of laying all types of submarine cables. It is equipped with a 7,000 ton turntable for high voltage cables and can simultaneously lay up to three cables in bundle configuration. Trenching and embedding machines are also available for cable protection.
Prysmian is listed on the Milan Stock Exchange and is indirectly controlled by Goldman Sachs. Its offices are located in 35 countries, with a total of 12,000 employees worldwide.
Siemens PTD and Prysmian were awarded a contract to turnkey the 400 megawatt Trans Bay Cable Project with a 53 mile HVDC transmission link between the City of Pittsburgh and San Francisco. Babcock and Brown closed construction financing in August 2007. Siemens PTD will be introducing HVDC ‘Plus’ at Trans Bay which reduces the size of the converter footprint by 40% and cuts in half the height of the buildings to 32 feet. Siemens plans to commission the project by 2010.
Internationally, Siemens PTD will commission the Storebelt HVDC Project in 2010 linking 600 megawatts between the islands of Fuen and Zealand in Denmark and the HVDC Britnet Project linking 1,000 megawatts between the UK and Rotterdam.
Of the 50 announced HVDC projects, fifteen are in China. The Guizhou-Guandong II HVDC Project will carry 3,000 megawatts from hydro and coal plants over 760 miles.
The latest Siemens PTD order in China is the link between the province of Yunnan and Guandang.
In India, the five regional power grids are not mutually compatible and nine HVDC projects are in commercial service. Siemens PTD and its consortium partner Bharst (BHEL) were awarded an HVDC contract by the Power Grid Corporation of India to install a 480 mile link between the province of Uttar Pradesh and Rajasthan. Commissioning is planned for November 2009.
Siemens Power Transmission and Distribution is headquartered in Erlangen Germany with a worldwide work force of 28,000 in 100 countries and sales of 6.5 billion euros.
‘Waves of the Future’
Submarine cable HVDC routes are interesting in view of the large offshore wind parks being planned. Based on present plans, wind parks will be constructed in the North Sea and the Baltic with power equaling several nuclear plants. This power has to be brought ashore over relatively long distances, and can only be effected with HVDC technology. Siemens predicts that Germany will have to start thinking about an HVDC link between Hamburg and Munich capable of transporting 2000 to 3000 megawatts.
Power delivery from the mainland not only increases the availability of the electric supply on the drilling rigs, but also ends the maintenance and servicing work for the small power plants currently used on the platforms.