
Electromagnetic Fields
One of the stressor topics the Triton Field Trials (TFiT) studies is electromagnetic fields.
Electromagnetic fields, often referred to as EMF, exist in throughout the world’s oceans naturally; many animals in marine systems use these fields to find prey, navigate, or migrate. As cables are installed throughout the world’s oceans for electricity or telecommunications, these electro-sensitive animals may be impacted by the disruption of natural magnetic fields by anthropogenic fields. For marine energy devices, there are EMFs generated by both cables transmitting electricity back to shore as well as the device itself. The Triton Field Trials for EMF is designed to determine which methods would most effectively measure EMF generated by marine energy devices.

Researchers are working hard to understand the field strength and spatial patterns associated with marine energy to determine how EMF might be impacting the marine environment. Currently, the intensity and variability of the magnetic fields generated by cables and devices are still largely unknown. The EMFs generated from electricity transmission underwater are typically of a similar magnitude to the background magnetic field of the Earth, so it is challenging to accurately measure the fields and quantify the effects on organisms.
During preliminary field trials, the Triton EMF team deployed a source cable in Sequim Bay to evaluate two different measurement devices: a purpose-built marine sensor for measuring magnetic fields and a low-cost, commercial sensor with a magnetometer. A variety of tidal current rates were examined to understand the tides’ impact on the strength of the EMF signal and the ability to measure the magnetic field. Additionally, a point source generator was deployed to mimic the electromagnetic fields generated by a device, such as a tidal turbine. In 2021, additional field trials will be conducted at multiple field locations, including a wave energy test site.