Huge underwater ‘kite’ turbine powered 1,000 homes in the Faroe Islands

It’s been over a decade since PopSci last checked in on Minesto’s underwater “kite” turbine technology. Since then, the Swedish green energy startup has made some big strides in their creative approach to generating clean electricity from swimming against the ocean currents. 

Last week, Minesto announced a major moment for their largest creation. A nearly 40-foot-wide, 30-ton, highlighter yellow Dragon 12 “tidal power plant” delivered its first 1.2 megawatts (MW) of energy to the Faroe Islands’ national grid. That’s enough power to sustain a small town of 1,000 homes.

[Related: Tidal turbines put a new spin on the power of the ocean.]

Although referred to as a “kite,” Dragon 12 arguably more resembles a biplane, and remains almost entirely below the ocean surface. Minesto’s video montage celebrating the inaugural voyage shows their tidal energy system leashed to a tugboat as it travels across an inland bay for installation.

Once installed, the Dragon 12 uses an onboard control system to steer its rudders. This allows continuous travel along a predetermined, countercurrent figure-8 pattern faster than surrounding water to rotate its turbine. The resulting generated energy then transfers down a subsea cable tether and to an onshore power facility through an umbilical line installed on the ocean floor.

The idea behind tidal green energy plants isn’t new, but for years the underlying technology has proven cost prohibitive and logistically difficult. Other designs are frequently massive endeavors. Scotland-based Orbital Marine Power’s 232-feet-long O2 turbine “superstructure,” for example, weighs in at nearly 700 tons while generating about 4 MW of power—a little more than four-times what Dragon 12 accomplished this month. Both approaches likely have their uses, but Minesto’s latest milestone indicates smaller, more modular, interlocked options could soon become available to energy providers.

And linking up multiple Dragon turbines is exactly what Minesto hopes to do next. According to The Next Web, the company intends to partner with a local Faroe Islands utility company to construct a 120MW system comprising around 100 tidal kite turbines. If successful, such a project could provide as much as 40-percent of the island archipelago’s entire electricity needs.

For microgrid plans, Minesto also has a smaller sibling to the Dragon 12. Dubbed the Dragon 4, this kite turbine system can generate 100kW of energy, and at just 13 x 16 x 9ft, can fit inside a standard shipping container for easy transport.