Deep Green underwater kite to generate electricity (w/ Video)

May 11, 2010 by Lin Edwards, report

The Deep Green technology converts energy from tidal stream flows into electricity by way of a novel principle, somewhat similar to the posture of a wind kite. Image credit: Minesto
( -- An underwater tidal turbine called an “underwater kite” has just secured finance from investors to ensure its 2011 tests can go ahead.

The turbine, known as “Deep Green” was developed by a privately-owned Swedish/UK company, Minesto, and is intended to be tethered 100 meters above the sea bottom. It has a wingspan of 12 meters and a turbine one meter in diameter. The “kite” comprises a wing with a rudder to steer the turbine to face in the direction that will allow it to capture the maximum amount of tidal energy, and generate up to 500 kW of electricity. The kite flies in a figure eight and travels 10 times faster than the water it is tethered in.

Ted Rosendahl, chief technical officer with Minesto, said the design will enable Deep Green to operate efficiently at greater depths and with lower current velocities than other tidal energy generators, which opens up new areas of the sea for tidal power generation, increasing the market potential by 80 percent, according to Minesto. Deep Green’s unique ability to work in deep water where there is low velocity water movement means it can operate cost effectively in areas otherwise unavailable for power generation.

There are two major types of tidal energy generator installations at present: one is the tidal barrage, which works in a similar way to a , and the other uses the flow of the tide and works in a similar way to wind power installations. In comparison with other tidal systems Deep Green is lightweight and much smaller, which translates to lower manufacturing costs.

The company will receive two million Euros (around 2.5 m USD) in investment funding, which will enable it to test a 1:4 scale prototype off the coast of Northern Ireland in 2011. The test site, at Strangford Lough, County Down is the location of a tidal generator owned by the UK company SeaGen. If the Deep Green trials are successful, the next step will be to test a full-scale demonstration plant consisting of up to 10 kites. Financing needed for this stage is expected to be around 40 million Euros.

Rosendahl said the company hopes a full-scale Deep Green generator will be commercially available within the next four years, adding to the available options for renewable energy sources. Tidal energy generation is usually more expensive than wind or solar power, but the predictability of the tides compensates for the extra initial cost, because unlike solar and wind energy, the tides operate every day of the year. Minesto says its Deep Green project is expected to be “very competitive in comparison with traditional electricity production.”

Minesto was formed in 2007 for the purpose of developing tidal power generators. Deep Green began as a Saab Group project in 2003, and Minesto was formed as a spin-off company.

Explore further: Oxford turbines to harvest energy from tides

Related Stories

Oxford turbines to harvest energy from tides

September 10, 2008

Oxford researchers have developed a new tidal turbine which has the potential to harness tidal energy more efficiently and cheaply, using a device which is simpler and more robust and scaleable than current designs.

Mersey River tidal power station proposed

November 22, 2005

The Mersey River may soon become the first river in Britain to generate electricity by tidal activity. The river, known for its leaping salmon, is now being tested as a possible renewable energy source.

Hydrokinetic proposal for Mississippi river

March 23, 2010

( -- Everyone is looking for alternative forms of energy, and one company proposes to generate electricity from the flow of the river Mississippi in the US, without using dams to control the water flow.

Recommended for you

Team breaks world record for fast, accurate AI training

November 7, 2018

Researchers at Hong Kong Baptist University (HKBU) have partnered with a team from Tencent Machine Learning to create a new technique for training artificial intelligence (AI) machines faster than ever before while maintaining ...


Adjust slider to filter visible comments by rank

Display comments: newest first

1.7 / 5 (3) May 11, 2010
Don't forget to add in the cost of transporting the energy, mining and smelting the ore for the cables, transporting the tech to the various locations it has to be built and installed, energy consumed in RnD process, etc... I'm not sure this product will end up being energy positive. Still, it's better than some options that are completely energy negative.
May 11, 2010
This comment has been removed by a moderator.
May 11, 2010
This comment has been removed by a moderator.
3.3 / 5 (3) May 11, 2010
I wonder how many tons of coal the toy trains powered by the tidal kites can transport.
1 / 5 (1) May 11, 2010
I can't help but suggest all these Lilliputian efforts uninspiring. Apparently, an overdose of politically correct pills triggered all kind of nonsense, including reincarnation of middle age technology (wind mills, kites). Contrast it with Thermonuclear: in this enterprise mankind aspires to a the level of stars!
not rated yet May 11, 2010
I can't help but suggest all these Lilliputian efforts uninspiring. Apparently, an overdose of politically correct pills triggered all kind of nonsense, including reincarnation of middle age technology (wind mills, kites). Contrast it with Thermonuclear: in this enterprise mankind aspires to a the level of stars!

Solar, tidal, and wind power are considered Type 1 technologies.

The problem with fusion is that it is NOT renewable because eventually you'd burn up the oceans, which means water must be replaced from comets. Additionally, to be efficient in terms of materials and long term energy resources, and not lose earth's mass, you'd need to store MASSIVE amounts of Helium possibly for millenia until you figure out how to make a Helium fusion reactor...

By the way, wind sails are INCREDIBLY efficient in terms of energy and materials in vs energy out. It may not be as FAST as burning fossil fuels or fission power plants ona ship, but it gets the job done with no cons.
5 / 5 (1) May 12, 2010
mongo, the trains can transport 40 tons of miniature sized coals
not rated yet May 12, 2010
well, if fusion goes big, the oceans are still bigger so it takes a pretty long time to burn m up, also reeling in comets and mining asteroids seem that much easier costeffective with a big nuclear hand and we coulkd always build a Shkadov engine to move the whole solarsystem once the yottawatts of fusion power come online and take our locust scavenging to the nearest molecular cloud
1 / 5 (1) May 12, 2010
The problem will be whales, these things may kill them.
Much like what windmills do to hawks. They're hauling asymptotes. Their "flight" path could be a killing zone. It may just be a big Waring Blender, and larger preditors, sharks, and whales would be toast. Surface ships collide with whales occasionally, no reason to think this won't. They make make enough noise to keep them away.

Energy is never free or without some environmental impact.
not rated yet May 12, 2010
I am concerned with this idea. It is great to be able to harvest the energy of the tide. It provides an excellent alternative to other renewable energy if there is a cloudy/windless day and at night. But does it produce enough electricity and at that depth, is it easy to service a broken one?

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.