This article needs to be updated.October 2012)(
Wave Dragon is a floating slack-moored energy converter of the overtopping type, developed by the Danish company Wave Dragon Aps. Wave Dragon is a joint EU research project, including partners from Austria, Denmark, Germany, Ireland, Portugal, Sweden, and the UK.It was the world's first offshore wave energy converter.
Denmark, officially the Kingdom of Denmark, is a Nordic country and the southernmost of the Scandinavian nations. Denmark lies southwest of Sweden and south of Norway, and is bordered to the south by Germany. The Kingdom of Denmark also comprises two autonomous constituent countries in the North Atlantic Ocean: the Faroe Islands and Greenland. Denmark proper consists of a peninsula, Jutland, and an archipelago of 443 named islands, with the largest being Zealand, Funen and the North Jutlandic Island. The islands are characterised by flat, arable land and sandy coasts, low elevation and a temperate climate. Denmark has a total area of 42,924 km2 (16,573 sq mi), land area of 42,394 km2 (16,368 sq mi), and the total area including Greenland and the Faroe Islands is 2,210,579 km2 (853,509 sq mi), and a population of 5.8 million.
Wave power is the capture of energy of wind waves to do useful work – for example, electricity generation, water desalination, or pumping water. A machine that exploits wave power is a wave energy converter (WEC).
The 237 ton prototype Wave Dragon was towed in March 2003 to the first test site at the Danish Wave Energy Test Center in Nissum Bredning fjord. It was tested until January 2005. In 2006 a modified prototype was deployed to another test site with more energetic wave climate. The prototype was scrapped in 2011.
The Limfjord is a shallow part of the sea, located in Denmark where it is regarded as a fjord ever since the Vikings. However it has inlets both from the North Sea and Kattegat and hence separates the island of North Jutlandic Island from the rest of the Jutland Peninsula. It extends from Thyborøn Channel on the North Sea to Hals on the Kattegat. It is approximately 180 kilometres long and of an irregular shape with numerous bays, narrowings, and islands, most notably Mors, and the smaller ones Fur, Venø, Jegindø, Egholm and Livø. It is deepest at Hvalpsund.
Wave Dragon is a floating, slack-moored energy converter of the 'overtopping' type which can be deployed as a single unit, or in arrays of up to 200 units; the output of such an array would have a capacity comparable to traditional fossil-fuel power plants.
The first prototype was connected to the power grid in 2003 and is currently deployed in Nissum Bredning, Denmark. Long term testing is under way to determine system performance; i.e. availability and power production under different weather and tide conditions. A multi-MW deployment is expected in 2009.
The Wave Dragon concept combines existing, mature offshore and hydro turbine technology. In the Wave Dragon, the Kaplan turbine is being tested at the Technical University of Munich. This turbine uses a siphon inlet whereas the next 6 turbines to be installed will be equipped with a cylinder gate to start and stop water inlet to the turbine.
Wave Dragon uses principles from traditional hydropower plants in an offshore floating platform to use wave energy.
The Wave Dragon consists of two wave reflectors that direct the waves towards a ramp. Behind the ramp, a large reservoir collects the directed water, and temporarily stores the water. The reservoir is held above sea level. The water leaves the reservoir through hydro turbines.
Three-step energy conversion:
Overtopping (absorption) -> Storage (reservoir) -> Power-take-off (low-head turbines)
Low head hydropower applications use tidal flows or rivers with a head of 20 metres (66 ft) or less to produce energy. These applications may not need to dam or retain water to create hydraulic head. Using the drop in a river or tidal flows to create electricity may provide a renewable energy source that will have a minimal impact on the environment.
Main components of a Wave Dragon:
Wave energy converters make use of the mechanical motion or fluid pressure. Wave Dragon does not have any conversion, e.g. oscillating water/air columns, hinged rafts, and gyroscopic/hydraulic devices. The Wave Dragon directly utilises the energy of the water's motion.
The Wave Dragon is of heavy, durable construction and has only one kind of moving parts: the turbines. This is essential for any device bound for operations offshore, where extreme conditions and fouling, etc., seriously affect any moving parts.
Wave Dragon model testing has been used in order to:
The main body to or platform consists of one large floating reservoir. To reduce rolling and keep the platform stable, the Wave Dragon must be large and heavy. The prototype used in Nissum is of a traditional (ship-like) plate construction of plates of 8 mm steel. The total steel weight of the main body plus the ramp is 150 tons, so that 87 tons of water must be added to achieve the 237 tons total weight needed for stable continuous operation.
A tension-leg platform (TLP) or extended tension leg platform (ETLP) is a vertically moored floating structure normally used for the offshore production of oil or gas, and is particularly suited for water depths greater than 300 metres and less than 1500 metres. Use of tension-leg platforms has also been proposed for wind turbines.
Vestas Wind Systems A/S is a Danish manufacturer, seller, installer, and servicer of wind turbines founded in 1945. The company operates manufacturing plants in Denmark, Germany, India, Italy, Romania, the United Kingdom, Spain, Sweden, Norway, Australia, China, and the United States, and employs more than 24,400 people globally.
Very large floating structures (VLFSs) or very large floating platforms (VLFPs) are manmade islands, which may be constructed to create floating airports, bridges, breakwaters, piers and docks, storage facilities, wind and solar power plants, for military purposes, to create industrial space, emergency bases, entertainment facilities, recreation parks, mobile offshore structures and even for habitation. Currently, several different concepts have been proposed for building floating cities or huge living complexes. Some units have been constructed and are presently in operation.
Subsea is fully submerged ocean equipment, operations or applications, especially when some distance offshore, in deep ocean waters, or on the seabed. The term is frequently used in connection with oceanography, marine or ocean engineering, ocean exploration, remotely operated vehicle (ROVs) autonomous underwater vehicles (AUVs), submarine communications or power cables, seafloor mineral mining, oil and gas, and offshore wind power.
The Wave Hub is a wave power research project. The project is developed approximately 10 miles (16 km) off Hayle, on the north coast of Cornwall, United Kingdom. The hub was installed on the seabed in September 2010, and is a 'socket' sitting on the seabed for wave energy converters to be plugged into. It will have connections to it from arrays of up to four kinds of wave energy converter. A cable from the hub to main land will take electrical power from the devices to the electric grid. The total capacity of the hub will be 20 MWe. The estimated cost of the project is £28 million.
Oceanlinx is a company created in 1997, specialised in renewable energy and especially in ocean energy conversion. Originally named Energetech, it will be renamed Oceanlinx in 2007. The main technology is based on Wave Energy Converter "WEC" which is a device that uses wave energy and converts it into electrical energy. The WEC operating principle are numerous but Oceanlinx technology focuses on the oscillating water column principle. Oceanlinx company was created in Australia and the technology has been developed over the past twenty years. In 2014, Oceanlinx entered receivership before its technology, intellectual property, brand and trademark were sold to Wave Power Renewables Limited in Hong Kong. Since then, Wave Power Renewables Limited has been developing the technology.
CETO is a wave-energy technology that converts kinetic energy from ocean swell into electrical power and directly desalinates freshwater through reverse osmosis. The technology was developed and tested onshore and offshore in Fremantle, Western Australia. In early 2015 a CETO 5 production installation was commissioned and connected to the grid. As of January 2016 all the electricity generated is being purchased to contribute towards the power requirements of HMAS Stirling naval base at Garden Island, Western Australia. Some of the energy will also be used directly to desalinate water.
The European Marine Energy Centre (EMEC) Ltd is a UKAS accredited test and research centre focusing on wave and tidal power development based in the Orkney Islands, UK. The Centre provides developers with the opportunity to test full-scale grid-connected prototype devices in unrivalled wave and tidal conditions. The operations are spread over five sites:
A floating wind turbine is an offshore wind turbine mounted on a floating structure that allows the turbine to generate electricity in water depths where fixed-foundation turbines are not feasible. Floating wind farms have the potential to significantly increase the sea area available for offshore wind farms, especially in countries with limited shallow waters, such as Japan. Locating wind farms farther offshore can also reduce visual pollution, provide better accommodation for fishing and shipping lanes, and reach stronger and more consistent winds.
A wind turbine, or alternatively referred to as a wind energy converter, is a device that converts the wind's kinetic energy into electrical energy.
Offshore wind power or offshore wind energy is the use of wind farms constructed in bodies of water, usually in the ocean on the continental shelf, to harvest wind energy to generate electricity. Higher wind speeds are available offshore compared to on land, so offshore wind power’s electricity generation is higher per amount of capacity installed, and NIMBY opposition to construction is usually much weaker. Unlike the typical use of the term "offshore" in the marine industry, offshore wind power includes inshore water areas such as lakes, fjords and sheltered coastal areas, utilizing traditional fixed-bottom wind turbine technologies, as well as deeper-water areas utilizing floating wind turbines.
Evopod is a unique tidal energy device being developed by a UK-based company Oceanflow Energy Ltd for generating electricity from tidal streams and ocean currents. It can operate in exposed deep water sites where severe wind and waves also make up the environment.
Marine energy or marine power refers to the energy carried by ocean waves, tides, salinity, and ocean temperature differences. The movement of water in the world’s oceans creates a vast store of kinetic energy, or energy in motion. Some of this energy can be harnessed to generate electricity to power homes, transport and industries.
A tidal stream generator, often referred to as a tidal energy converter (TEC), is a machine that extracts energy from moving masses of water, in particular tides, although the term is often used in reference to machines designed to extract energy from run of river or tidal estuarine sites. Certain types of these machines function very much like underwater wind turbines, and are thus often referred to as tidal turbines. They were first conceived in the 1970s during the oil crisis.
IEC 61400 is an International Standard published by the International Electrotechnical Commission regarding wind turbines.
The DeepCwind Consortium is a national consortium of universities, nonprofits, utilities, and industry leaders. The mission of the consortium is to establish the State of Maine as a national leader in floating offshore wind technology. Much of the consortium's work and resulting research has been funded by the U.S. Department of Energy, the National Science Foundations, and others.
The VolturnUS is a floating concrete structure that supports a wind turbine, designed by University of Maine Advanced Structures and Composites Center and deployed by DeepCwind Consortium in 2013. The VolturnUS can support wind turbines in water depths of 150 ft (46 m) or more. The DeepCwind Consortium and its partners deployed a 1/8th scale VolturnUS in 2013. Efforts are now underway by Maine Aqua Ventus 1, GP, LLC, to deploy to full-scale VolturnUS structures off the coast of Monhegan Island, Maine, in the UMaine Deepwater Offshore Wind Test Site. This demonstration project, known as New England Aqua Ventus I, is planned to deploy two 6 MW wind turbines by 2020.
MARMOK-A-5 is an offshore electrical power generator that uses wave energy to create electricity. This device is a spar buoy installed in the maritime testing site Bimep, in the Bay of Biscay. It is the first grid connected maritime generator in Spain, and one of the first in the word.