This article is written by Paige Medley, Consultant at Smarter Grid Solutions
Thanks in large part to the ambitious Reforming the Energy Vision (“REV”) proceeding, the Governor’s call for 2.4 GW of offshore wind has prompted industry giants such as Statoil and Deepwater Wind to invest in New York’s nascent offshore wind market. They have leased two large parcels off the coast of Long Island, and these projects are seen as the gateway to more offshore development in New York State.
New York State highest offshore wind potential in the Northeast
The highest quality offshore wind resources are adjacent to the largest load centers in the state, along the coast of Long Island and in Lakes Erie and Ontario. The American Wind Energy Association (AWEA) estimates that New York State has the largest wind energy potential in the Northeast, capable of producing up to 62 billion kWh annually, and powering upwards of 15 million homes.
HVDC vs. AC transmission infrastructure
One of the major challenges New York will face is the interconnection of planned offshore wind developments to the electric grid. New transmission infrastructure will be required and cost will be a significant consideration in dictating which technology is adopted. The two options for interconnection are traditional Alternating Current (AC) or High-Voltage Direct Current (HVDC). Almost all of the transmission infrastructure in the United States today consists of AC lines, and for short transmission lines AC is typically the more cost effective of the two options.
While HVDC has higher CAPEX costs, DC transmission infrastructure minimizes energy loss when transporting large quantities of energy across long distances. The amount of energy saved over the lifetime of the project will be significant, and result in direct cost savings to the developer.
In the UK, the offshore wind market has exceeded all growth expectations. Developers in the UK are responsible for constructing the transmission links that connect the main grid to wind farms, and have historically turned to the lower-cost AC alternative. In planning for NY’s 2.4 GW of offshore wind, regulators and developers will benefit from keeping this multi-gigawatt goal in mind by installing HVDC, instead of interconnecting using lower-cost AC.
According to a study conducted by Strathclyde University, "the costs associated with the energy lost during transmission are substantially larger for the AC option deployed across a long distance than for the HVDC option.” Over the long term, this upfront investment will result in fewer power losses, reducing the annualized costs of transmission, and providing Long Island with more efficient wind-generated power at a lower overall project cost.
As GTM reports, the installation of HVDC over AC cabling starts to make sense when you are exporting more than 1 GW, or when the cabling distance is longer than 30 miles. The 90 MW Deepwater Long Island project is sited 30 miles from the Long Island Shore, making the near-term installation of HVDC cabling for this project more cost-effective than AC cabling.
Join the conversation at the NY REV Energy Future Event
While offshore wind is a part of the 50 by 30 puzzle, there are many updates that will need to be made to the onshore transmission and distribution grids as well. Smarter Grid Solutions’ CTO Bob Currie will be speaking at New York REV’s Energy Future Conference to discuss New York State’s renewable energy future, and how advanced grid technologies such as ANM can help utilities, developers and NY State meet its renewable goals.