Speaker
Description
Introduction
Offshore and marine renewable energy development and electricity transmission are accelerating globally, with more subsea high-voltage alternating current (HVAC) and high-voltage direct current (HVDC) cables being deployed. These cables generate magnetic fields within the marine environment, inducing electric fields. This report builds on previous EPRI research to further understand these time-varying electromagnetic fields (EMFs) and their potential effects on marine animals.
Methods
A comprehensive review of laboratory and field evidence was conducted to assess the effects of HVAC and HVDC cables on marine animals. A modeling approach was developed to estimate EMFs in the water column and seabed, considering environmental factors such as water movement and interaction with the Earth's geomagnetic field. A framework was developed to help guide environmental assessments and determine the likelihood of EMF-animal encounters and potential effects, incorporating the modeling approach and in light of incomplete scientific knowledge on marine impacts.
Results
Marine animals, including elasmobranchs (sharks, skates, and rays), cetaceans (whales and dolphins), turtles, and some migratory teleost fish, use EMFs for important life processes. Elasmobranchs are highly sensitive to electric fields, while cetaceans, turtles, and some fish are sensitive to magnetic fields. Laboratory and field evidence indicates that existing HVAC and HVDC cables generate EMFs at levels detectable by these animals. However, the impact of these EMFs at the population level is still unclear.
Funding: Studies were funded by the Electric Power Research Institute (EPRI).
