TY - RPRT
TI - Sunrise Wind COP Appendix J2: Onshore EMF Assessment
AU - Exponent Engineering PC
AB - This report supplements the Sunrise Wind Construction and Operations Plan.Orsted North America Inc. (Orsted NA) and Eversource Investment LLC (Eversource) have proposed the Sunrise Wind Farm Project (the Project) to be located off Rhode Island and Long Island, New York. The electricity generated by the Project will be brought to shore over direct current (DC) submarine cables and then delivered by an underground Onshore Transmission Cable to the Onshore Converter Station (OnCSDC). At the OnCS–DC, the electricity is converted to 60 Hertz (Hz) alternating current (AC) at 138 kilovolts for transmission over the underground Onshore Interconnection Cable to the existing Holbrook Substation in the Town of Brookhaven, New York. At the request of TRC Environmental Corporation (TRC) and Sunrise Wind LLC (Sunrise Wind), Exponent Engineering PC (Exponent) calculated the DC and AC magnetic fields associated with the operation of these onshore underground cables.  The Onshore DC Transmission Cable will produce a DC magnetic field that will, in turn, produce a local change in the Earth’s geomagnetic field in the area immediately surrounding the cable. The resulting deviations from the Earth’s ambient geomagnetic field and compass deflections will diminish rapidly with distance. The highest total magnetic field from the cable at 3.3 feet (ft) (1 meter [m]) above ground at average loading is 653 milligauss (mG), and at peak loading is 780 mG, which reflects the contribution from the ambient geomagnetic field of 506 mG and a maximum increase from the DC cables of 147 mG and 275 mG for average and peak loading, respectively. Elsewhere on the Onshore Transmission Cable route, the cables are calculated to reduce the ambient geomagnetic field to a minimum of 360 mG and 236 mG for average and peak loading, respectively, which reflects the contribution from the ambient geomagnetic field of 506 mG and respective reductions of 146 mG and 270 mG. Over the few tens of feet where cables are separated from one another at the Transition Joint Bay, DC magnetic-field levels will be higher, but also decrease rapidly with distance, deviating from the ambient geomagnetic field by 99 mG or less at ±25 ft (7.6 m) from the cables at 3.3 ft (1 m) above ground. The calculated DC magnetic-field levels are far below the International Commission on Non-Ionizing Radiation Protection’s standard for human exposure to static (i.e., DC) magnetic fields (i.e., < 0.1 percent of the general public exposure limit of 4,000,000 mG) for all cable configurations evaluated. The highest calculated magnetic field is also well below the applicable medical device standard of 10,000 mG for exposure of implanted medical devices to static magnetic fields. These calculated AC magnetic fields are well below the New York State Public Service Commission’s limit of 200 mG from 60-Hz magnetic fields from new transmission lines at right-of-way edges.The DC and AC magnetic-field levels within the OnCS–DC were not calculated, since fields from sources within will be minimal outside the boundaries of the OnCS–DC. The dominant sources of magnetic fields at the perimeter of the OnCS–DC will be the new underground Onshore Transmission Cable and the new underground Onshore Interconnection Cable. 
DA - 2022/08//
PY - 2022
SP - 68
PB - Exponent Inc.
UR - https://www.boem.gov/renewable-energy/state-activities/sunrise-wind-construction-and-operation-plan
LA - English
KW - Wind Energy
KW - Fixed Offshore Wind
KW - EMF
ER -