Newtechnology may end the longstanding problem of collisions between ship anchorsand underwater electric transmission cables, according to a recent announcementfrom the New York Power Authority.
Thatadvancement could make it easier for utilities to expand transmission incongested or otherwise complicated areas where routing the lines underwater isthe most feasible option.
A "virtualbeacon system" installed by the public power organization uses cloud-basedsoftware to help prevent anchor strikes that have at times crippled NYPA's26-mile, 345-kV cable that runs through Long Island Sound.
"Costlycollisions between ships and underwater cables are becoming increasinglycommon. We hope that by adopting this proactive strategy, anchor strikes willsoon be regarded as events from a bygone era," NYPA President and CEO GilQuiniones said in a July 11 statement.
As demand grows to take renewable energy resources sited inrural areas and link it to dense, heavily populated urban communities, theremay be increasing need for underwater approaches to transmission. Toronto-baseddeveloper oneGRID Corp.and investment firm Forum EquityPartners recently proposeda 320-kV direct-current transmission line that would connect Utica, N.Y., toNew York City by running below the Erie Canal and Hudson River to give upstatepower suppliers "unfettered access" to the city. Aportfolio company of BlackstoneGroup LP, TransmissionDevelopers Inc. affiliate TDI New England, wants to the New England CleanPower Link to transport hydroelectric and wind power from Canada into NewEngland, and about 97 miles of that 152-mile line would run under LakeChamplain.
The Long Island Sound cable is a "critical" partof NYPA's power lines, which make up about a third of the high-voltagetransmission capacity in New York state, according to the statement.But since it was put into service in 1998, the line has twice beenstruck by anchors. NYPA spent millions of dollars on repairing the cable aftera ship inadvertently dropped an anchor on it in January 2014.Following that incident, NYPA sought out vendors to provide a system that wouldhelp avoid more anchor strikes.
That request for proposals led to the recently deployedsystem, called the WatchMate Asset Protection and made by the New Zealandcompany Vesper Marine. The system collects data on ship position, speed anddirection and automatically sends alerts to ships close to the cable, warning themnot to drop anchor. It also uses "virtual beacons"that appear on marine navigation systems to warn ships that they are in thevicinity of a cable.
NYPA has also previously explored building wind farmsoffshore. It collaborated with the LongIsland Power Authority and ConsolidatedEdison Inc. on the Long Island-New York City Offshore Wind Project.But NYPA no longer has the "lead role" in any offshore wind projects,according to NYPA spokesman Steven Gosset, and the New York State EnergyResearch and Development Authority plans to participate in afederal auction for a commercial offshore wind energy lease near Long Island.
In addition, the virtual beacon technology might be lessrelevant for offshore wind. "Given that some of the offshore wind projectsbeing contemplated are well out to sea, it is less likely that a ship would beanchoring that far out, especially in an ocean area," Gosset said. "However,this is the kind of technology that could be deployed to protect cables used bywind turbines."
Most offshore wind projects involve cables that aretypically buried over one meter under the seabed, and usually there is an "exclusionzone" around an offshore wind farm which unauthorized ships cannot enter,according to the Business Network for Offshore Wind. Also, most vessels thatinstall cables and transfer crew for offshore wind farms are "dynamicpositioning" vessels that do not use anchors.
But some export cables that bring offshore wind'selectricity to land can be unburied due to rocky or moving seabeds. The anchoralert technology could be helpful for those types of cables, the BusinessNetwork said.