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).
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.
The Pelamis Wave Energy Converter was a technology that used the motion of ocean surface waves to create electricity. The machine was made up of connected sections which flex and bend as waves pass; it is this motion which is used to generate electricity.
The Wave Hub is a floating offshore wind and 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 was a company established in 1997 which specialised in the research and development of ocean-based renewable energy technology. The company's central technology was based on the Wave Energy Converter "WEC" which converts wave energy into electrical energy. Oceanlinx technology focused on the oscillating water column principle, and developed several prototype generators which were deployed and tested in Port Kembla, New South Wales. In 2014, Oceanlinx entered receivership and its technology, intellectual property, brand and trademark were sold to Wave Power Renewables Limited in Hong Kong. Wave Power Renewables Limited has continued to develop the technology, and Oceanlinx's founding director, Tom Denniss has further developed the technology since 2016 as a director of Wave Swell Energy.
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 center focused 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 wave and tidal conditions.
Ocean Power Technologies (OPT) is a U.S. publicly owned renewable energy company, providing electric power and communications solutions, services and related for remote offshore applications. The company's PowerBuoy wave energy conversion technology is theoretically scalable to hundreds of megawatts and the generated energy from wave power can be supplied to the grid via submarine cables. Several projects were undertaken around the world, but the economic viability of the theoretical concept has been problematic.
The Oyster was a hydro-electric wave energy device that used the motion of ocean waves to generate electricity. It was made up of a Power Connector Frame (PCF), which is bolted to the seabed, and a Power Capture Unit (PCU). The PCU is a hinged buoyant flap that moves back and forth with movement of the waves. The movement of the flap drives two hydraulic pistons that feed high-pressured water to an onshore hydro-electric turbine, which drives a generator to make electricity. Oyster was stationed at the European Marine Energy Centre (EMEC) at its Billia Croo site in Orkney, Scotland until the company ceased trading in 2015.
The Lysekil project is an ongoing wave power project which is run by the Centre for Renewable Electric Energy Conversion at Uppsala University in Sweden.
The Oceanic Platform of the Canary Islands (PLOCAN) is a singular scientific and technological infrastructure (ICTS) aimed to accelerate the development of knowledge and technologies for the responsible and sustainable use of the ocean, in line with the United Nations Sustainable Development Goals and strategy of Blue Growth Strategy established by the European Union. It has been partially co-funded by the European Regional Development Fund (ERDF) under the ERDF Operational Programme for the Canary Islands 2007-2013 within Axis 1 "Development of the Knowledge Economy", priority theme 02, with a co-financing rate of 85%. PLOCAN is financed and managed by a consortium comprising 50% contributions from the Government of the Canary Islands and the Spanish National Government.
Oscillating water columns (OWCs) are a type of wave energy converter that harness energy from the oscillation of the seawater inside a chamber or hollow caused by the action of waves. OWCs have shown promise as a renewable energy source with low environmental impact. Because of this, multiple companies have been working to design increasingly efficient OWC models. OWC are devices with a semi-submerged chamber or hollow open to the sea below, keeping a trapped air pocket above a water column. Waves force the column to act like a piston, moving up and down, forcing the air out of the chamber and back into it. This continuous movement forces a bidirectional stream of high-velocity air, which is channeled through a power take-off (PTO). The PTO system converts the airflow into energy. In models that convert airflow to electricity, the PTO system consists of a bidirectional turbine. This means that the turbine always spins the same direction regardless of the direction of airflow, allowing for energy to be continuously generated. Both the collecting chamber and PTO systems will be explained further under "Basic OWC Components."
Located on the east side of Gibraltar, on a former World War II ammunition jetty, the Gibraltar Wave Farm is the first commercial, grid-connected wave energy power station in all of Europe. The project utilizes the devices of Eco Wave Power Ltd, an Israel-based wave energy company. The wave farm was initially launched with an estimated peak capacity of 100 kW in April 2016 and plans for expansion to 5 MW within the next years. The project is operating through a 25-year PPA between Eco Wave Power, the Government of Gibraltar, and the Gibraltar Electricity Authority. Upon completion, it is expected generate 15% of the total electricity consumption of Gibraltar. The project is funded, in part, by the 2014-2020 European Regional Development Fund, in order to put the country in line with the EU's renewable energy goal: 20% energy generated from renewable power by 2020. The project is also funded by private investment groups. As of February 2018, the Gibraltar Wave Farm accrued 15,000 grid connected hours, a new world record for wave energy plant.
Wave Energy Scotland (WES) is a technology development body set up by the Scottish Government to facilitate the development of wave energy in Scotland. It was set up in 2015 and is a subsidiary of Highlands and Islands Enterprise (HIE) based in Inverness.
Sotenäs is a wave farm located in Kungshamn, in the municipality of Sotenäs, Sweden. The facility consists of 36 wave energy converters (WECs), with a total installed capacity of nearly 3 MW. Each WEC generates power using point absorber buoys connected to linear generators on the seabed. The generators are located at a depth of 50 m (160 ft). According to Seabased, the technology used in the project could deliver electricity for under 10 cents per kWh. Initial announcements stated that the power plant would eventually expand to around 10 MW capacity, but in 2017 Seabased announced it would no longer expand the plant beyond the 36 WECs already in place.
Mocean EnergyLtd. is a wave energy technology developer, based in Edinburgh and Aberdeen. They are developing a hinged-raft attenuator wave energy converter (WEC) at various scales for different markets.
Many tidal stream generators have been developed over the years to harness the power of tidal currents flowing around coastlines. These are also called tidal stream turbines (TST), tidal energy converters (TEC), or marine hydro-kinetic (MHK) generation. These turbines operate on a similar principle to wind turbines, but are designed to work in a fluid approximately 800 times more dense than air which is moving at a slower velocity. Note that tidal barrages or lagoons operate on a different principle, generating power by impounding the rising and falling tide.
Minesto AB is a Swedish developer of electricity producing tidal kite turbines, based in Gothenburg. They also have a manufacturing base in Holyhead, North Wales, and a test facility at Portaferry, Northern Ireland.
CorPower Ocean AB is a wave energy device developer, headquartered in Stockholm, Sweden. They also have offices in Oslo, Viana do Castelo, and Stromness. The office in Viana do Castelo is an R&D centre that also serves as the manufacturing and service centre for the wave energy converters (WEC).
The Aguçadoura test site is an offshore location in the north of Portugal where grid connected offshore renewable energy devices have been tested, for research and project demonstration. It is about 5 km (3 miles) off the coast of Aguçadoura, Póvoa de Varzim, about 35 km NNE of central Porto.
