Oyster wave energy converter

The Oyster is a hydro-electric wave energy device that uses the motion of ocean waves to generate electricity. It is 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 is stationed at the European Marine Energy Centre (EMEC) at its Billia Croo site in Orkney, Scotland.
Aquamarine Power installed Oyster at the EMEC in August 2009. On 20 November 2009, Oyster was officially launched and connected to the National Grid (UK) by the First Minister of Scotland, Alex Salmond.
Current developments are underway to build a more efficient and powerful second-generation device, Oyster 2.
History.
Oyster was developed by Edinburgh-based Aquamarine Power, a company that focuses on wave energy. The concept originated from research at Queen’s University, Belfast, led by professor Trevor Whittaker, Head of the Wave Power Research Centre at Queen's. Aquamarine Power also teamed up with Renewable Technology Ventures Ltd (STVL), a subsidiary of Scottish and Southern Energy (SEE), to fund the Oyster project. Aquamarine Power was able to secure a £6.3m investment from Scottish Enterprise. In addition, Scottish Enterprises awarded Aquamarine Power a £3.15 million grant from the Wave and Tidal Energy: Research, Development and Demonstration Support fund (WATERS). Aquamarine Power also received £1.5m from Sigma Capital Group plc. Altogether, Aquamarine Power was able to raise £11 million to stage this project.
In June 2009, Aquamarine Power signed a £2.5 million contract with Fugro Seacore to install the Oyster device at the European Marine Energy Centre test site at Billia Croo. Oyster was installed 400 metres offshore, west of the Orkney mainland, in 12 metre-deep water. Oyster was installed in August 2009; however it was officially launched on 20 November 2009 by the First Minister of Scotland, Alex Salmond. That same day, Oyster was connected the National Grid (UK) and began generating electricity.
Aquamarine Power hoped to commercialize Oyster and has already signed an agreement with Scottish and Southern Energy to develop up to 1000MW of wave farms by 2020. However, the test programme ended in 2015, when the company failed to find investors and ceased trading. 
Operation.
Oyster harnesses the energy of near-shore ocean waves; it was designed to operate in water 10 to 12 metres deep. The Oyster is made up of a Power Connector Frame (PCF) and a Power Capture Unit (PCU). The 36-ton PCF is bolted to the seabed by 1-by-4 meter concrete piles that are drilled 14 metres deep into the seabed. The PCF requires careful and accurate positioning and leveling to compensate for the uneven, rocky seabed. The PCU is a 200-ton, 18-by-12-by-4 metre buoyant flap that is hinged to the PCF. In order to lower the PCU into the water to hinge it to the PCF, 120 tons of seawater must be pumped into ballast tanks within the PCU to provide sufficient negative buoyancy to aid its descent into the water. The PCU is almost entirely submerged underwater; only 2 metres of the device poke above the water. The PCU sways back and forth with the movement of the waves, and this movement of the flap drives two hydraulic pistons that pump high-pressured water through three sub-sea pipeline to an onshore hydro-electric water turbine. The turbine then drives a 315 kW electrical generator, which converts the wave energy into electricity.
The European Marine Energy Centre classifies Oyster as an Oscillating Wave Surge Converter:
Potential.
There are several advantages to using a device like the Oyster:
Challenges.
There are also many disadvantages to using a device like the Oyster:
Oyster Version 2.
Current developments are underway to construct an improved, second-generation Oyster device, Oyster 2. In December 2010, Aquamarine Power signed a £4 million contract with Scotland’s leading fabrication contractor Burntisland Fabrications Ltd (BiFab). BiFab began manufacturing Oyster 2 at its manufacturing plant in Methil, Fife, Scotland, and the device is expected to be in full operation by the summer rine Energy Centre]].
Aquamarine Power has secured funding from many sources for the development of Oyster 2:
Oyster 2 will employ the same basic technology of the original Oyster; however, it will feature a different shape that will maximize the amount of energy that the device is able to capture from the waves. Oyster 2 will consist of three 800 kW flaps that will all be linked to one pipeline leading to an onshore 2.4 MW hydro-electric generator. Each flap will measure 26 metres, making it 50% larger than the original Oyster. Oyster 2 will also have a 250% greater power output. Aquamarine Power estimates that a small farm of 20 Oyster 2 devices will be capable of supplying enough electricity for over 12,000 homes, compared to the 9,000 homes the original Oyster is capable of powering.
At the European Marine Energy Centre’s Billia Croo site, a single Oyster 800 rated at 800 kW was grid-connected in June 2012 and will undergo testing until 2015. By mid 2014 the Oyster 800 had completed 20,000 hours of operation.