The Faroe Islands government has a goal of running entirely on renewable power by 2030. The country has a vast resource to draw on in tidal energy in the fjords.
To capitalize on the strong underwater currents, marine engineers came up with a subsea tidal kite design that looks like a dragon and installed two of them in a marine channel.
This technology has not been approved for commercial deployment yet, but environmental monitors are using the operational turbines as passive acoustic whale recorders. How do the two types of tech work hand-in-hand?
How to tap tidal energy in narrow North Atlantic fjords
The autonomously governed volcanic Faroe Islands lie between Iceland and Norway in the North Atlantic Ocean. There are narrow channels of sea between the 18 islands in the cluster that create fast undersea currents.
The island nation relies on diesel, which has to be imported, but it also has several hydropower and wind installations.
Regional utility companies with the aim of cutting fuel costs recently collaborated with the Swedish energy company Minesto to test the predictability of marine flows.
The fresh kite design operates differently than fixed seabed turbines. This tethered system sees the turbine “flying” loops underwater, which is how energy is generated.
The Vestmannasund deployment framework includes two Dragon 4 kites—the units designated for environmental monitoring upgrades—alongside a larger 1.2-megawatt Dragon 12 system, together representing a planned 1.4-megawatt mini-array.
The plan is to expand from this pilot to a 200-megawatt network, but first, it had to be proved that the moving equipment would not strike the marine wildlife.
The channel is regularly visited by long-finned pilot whales, harbor porpoises, and white-sided dolphins, and there is regulatory concern about noise pollution that disrupts the animals’ behavior and collision risk.
Clean power must be balanced with marine conservation
Environmental assessment and baseline monitoring are integrated into the site development and licensing process in coordination with Faroese regulatory authorities.
The process had to go beyond standard visual surveys from boats decks, because it does not work in such deep and turbulent waters or in the dark winter months.
The environmental monitoring process had to be moved underwater. Ongoing environmental studies focus on evaluating potential interactions with local marine mammals to satisfy regulatory oversight.
The result will be an extensive acoustic record of whether diving whales, dolphins, and porpoises avoid the equipment or continue to use the channels as feeding grounds.
The installation of independent monitoring buoys was not easy, because the tidal currents are so strong that the surface floats get dragged.
The solution was to mount the listening hardware onto the kites’ frames. This turns the turbines themselves into listening stations, and now, the researchers have a stable acoustic platform without adding more gear to the seafloor.
Underwater dragons double as acoustic whale listeners
The subsea Dragon 4 kites are undergoing upgrades to support future environmental monitoring capabilities, including acoustic noise measurements, bird tracking, and marine mammal observation, according to Tethys.
Environmental monitoring equipment is being integrated into the project framework.
As the kite sweeps figure-eight patterns underwater, these listening devices catch high-frequency echolocation clicks from porpoises and low-frequency calls from migrating pilot whales up to several hundred yards away.
To separate animal sounds from background noise, onboard software filters out low-frequency noise produced by spinning generator blades and rushing water. The system isolates specific cetacean vocal patterns, logging spatial location, frequency, and signal arrival angles.
Data collection protocols are being established as part of the upgrade program to gather environmental information during site operations.
Tracking continues in storms and darkness
Using the kite’s built-in power supply and data connection allows the acoustic sensors to track marine mammals constantly during heavy storms and dark conditions.
Field assessments are intended to evaluate how local marine life interacts with the operating units, with formal tracking logs and behavioral findings regarding cetacean responses still under study.
Successfully testing onboard listening tech provides the empirical safety data needed to evaluate expanded 200-megawatt subsea arrays, ensuring tidal power generation coexists safely with North Atlantic marine life.
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