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U.K. company refines wave energy converter

Offshore Wave Energy Ltd. (OWEL) of the United Kingdom has begun a new phase of research into its Grampus wave energy converter, studying the geometric configuration of the device to optimize its performance.

OWEL’s Grampus device is to convert ocean wave energy into compressed air to drive a turbine and produce electricity. The Grampus unit consists of a tapered, horizontal duct floating on the ocean. As a wave enters the duct, air is trapped in the duct and is compressed between the wave and the stationary upper surface of the duct. This compressed air is taken from the duct through a valve and used to drive a conventional unidirectional turbine.

OWEL’s research has been funded by a grant from the United Kingdom’s South West Regional Development Agency (SWRDA) and from contributions of shareholders.

In addition to studying internal geometric configuration of the device, the SWRDA-funded study is to investigate the unit’s structural loading and mooring requirements. The work will utilize computational fluid dynamics (CFD) modeling and a series of tank tests in a selected wave basin. On completion, OWEL said it would have an optimized full-scale design and a more detailed understanding of its performance and cost characteristics.

The next step in development of the technology involves construction of a prototype to be deployed in the ocean. OWEL hopes to deploy a three-quarter-scale unit at the European Marine Energy Center (EMEC) in Scotland’s Orkney Islands.

OWEL was formed in 2001 by Kemp, Sycamore Projects - Marine, IT Power Ltd., and Business Link Wessex. Other partners include the New and Renewable Energy Center.


Leighton Contractors to develop wave sites in Australia

Wave energy developer Ocean Power Technologies (OPT) of the United States is working with Australia infrastructure developer Leighton Contractors Pty Ltd. to install wave power projects off Australia’s eastern and southern coasts. A wave power assessment of the southern Australia coast recently found 170,000 MW of potential near-shore wave energy potential.

Under contract with Leighton, OPT subsidiary Ocean Power Technologies (Australasia) Pty Ltd. will identify potential project sites and assess their commercial prospects. Upon identification of projects to be developed, Leighton is to obtain approvals, negotiate power purchase agreements, structure project financing, and oversee project delivery and operation. OPT is to sell its PowerBuoy wave power stations to special-purpose companies formed by Leighton for the projects.


The PowerBuoy, from Ocean Power Technologies, will be installed at sites off Australia’s eastern and southern coasts.
Click here to enlarge image

In September 2008, OPT deployed a 40-kW PowerBuoy generator in Spain as part of the 1.39-MW Santona wave energy project. OPT has a tentative deal to develop nine more powerful versions of the buoy over the next year and eventually create a PowerBuoy farm for Spanish utility Iberdrola, capable of generating enough electricity to supply up to 2,500 homes annually.


Hungarian company developing RiverPower technology

Power of the Dream Ventures, Inc. in Hungary is developing RiverPower, a technology designed to convert the flow of rivers into electricity without the need to build a dam.

RiverPower is submerged in the river and anchored to the riverbed. The unit does not feature a traditional turbine. Instead, it consists of several interlocking wheels, each with “flippers” that fold out, resembling a waterwheel. The wheels transfer rotational torque created by the flow of water to a single axis (or shaft), which drives the generator. The slow-speed generator (5 to 15 revolutions per minute) can produce electricity from flows as low as 0.9 meter per second. The units can be installed one right after the other in a line down the river. Each machine can produce about 50 kilowatt-hours of electricity.

The unit was tested in 2008 at VITUKI Consult Environmental and Water Management Research and Consulting Ltd. Tests took place in a 70-meter-long, 1.5-meter-wide channel. Rather than moving water through a stationary device, the one-fourth-scale prototype was moved in the water through the length of the channel. During testing, the company measured the torque transferred to the shaft to determine the unit’s potential power generating characteristics.

The company is now conducting the final round of work to optimize the technology and determine the final design of the unit. This work was scheduled to be complete by the end of March 2009.

The next step is to install a full-sized machine in a river in Hungary and perform testing by the end of August 2009. This unit will use a new generator patented by Power of the Dream Ventures, says Viktor Rozsnyay, president and chief executive officer.


Tidal Energy to launch 1-MW project in Wales

Tidal Energy Ltd. in Wales is working to launch a 1-MW prototype tidal stream project in Ramsey Sound in the West Wales. Tidal Energy plans a single DeltaStream device with nominal installed capacity of 1 MW, to be deployed for 12 months.

The developer said it considers a 12-month period sufficient testing time to commercialize the Delta-Stream technology. It said the Delta-Stream concept was first conceived in 2001 with the support of Pembrokeshire Coast National Park.

A 1-MW DeltaStream unit includes three horizontal-axis turbines on a 30-meter-wide triangular frame. Tidal Energy said its patented blade design enables the turbine automatically to shed excess power, avoiding damage from excessive peaks in tidal flow and permitting consistently high energy conversion. The rotors rotate more slowly than other tidal stream devices, allowing marine animals to avoid them. The frame is to provide a low center of gravity that allows the unit to sit on the seabed with no positive anchoring or seabed drilling. The base technology previously was developed by Tidal Hydraulic Generators Ltd.

The Ramsey Sound project is to include a subsea cable, an onshore control room and substation, and electrical infrastructure to connect with the local distribution network.

Tidal Energy is a privately financed company in Cardiff, the Welsh capital.


India developer to begin building 3.75-MW Durgaduani Tidal

India developer NHPC Ltd. is moving forward with construction of the 3.75-MW Durgaduani Tidal Power project in West Bengal State.

The project is being funded by owner West Bengal Renewable Energy Development Agency and India’s Ministry of New and Renewable Energy. NHPC planned to choose a company to develop the project in February 2009.

Work is to include planning, design, engineering, and execution of all civil structures such as a dike, inlet sluice, powerhouse, and switchyard. The company chosen to build the project also will design, manufacture, install, and commission three 1.25-MW bulb turbine-generators, ancillary equipment, switchyard, and hydro-mechanical equipment such as vertical lift gates, stoplogs, hoists, and gantry cranes. The work is to be performed over two years.


OpenHydro to build France’s Paimpol-Brehat tidal

Electricité de France (EDF) and Irish tidal power developer OpenHydro Group Ltd. are working to install four to ten tidal power turbines at EDF’s pilot project at Paimpol-Brehat, on France’s northern Brittany coast. EDF said Paimpol-Brehat should have a total capacity of 2 to 4 MW for delivery to the French grid by 2011.

The utility said the test site would enable the technology to be tested in actual conditions and its environmental effects to be assessed in detail.

EDF previously said the project is to involve an investment of 23 million to 27 million euros (US$36.7 million to US$43.1 million) that EDF will finance jointly with local and European authorities.

OpenHydro, a designer and manufacturer of marine turbines, holds world rights to the Open-Centre Turbine technology. The company’s commercial-scale test turbine is operating at the European Marine Energy Center in Orkney, Scotland. EDF said the technology requires no underwater work and that the fully submerged turbines easily can be raised for maintenance.


U.K. plans to develop 700 MW at Pentland Firth

The United Kingdom’s Crown Estate plans to develop 700 MW of ocean generation at Pentland Firth in Scotland by 2020. The Crown Estate, which protects and manages government resources to benefit the taxpayer, said Pentland Firth has six of the top ten sites in the United Kingdom for tidal power development. Both wave and tidal power technology could be used at this site.

Several companies are investigating the possibility of developing ocean generation at this site, including Scottish Power Renewables and tidal developer Marine Current Turbines.

The Crown Estate’s Round 1 leasing program is aimed at delivering 700 MW of new offshore wave and tidal power by 2020, bringing significant economic benefits to northern Scotland. The initial devices to be installed are expected to be full-sized demonstration units deployed in small arrays. Larger scale development might require improvements to the grid, the agency said, and full-scale commercial development definitely would require significant investment in the grid.

Technologies to be installed at this site are to be selected in mid-2009.


Israel wave power developer announces African concession

Israeli wave power developer SDE Energy Ltd. is working to build sea wave power plants totaling 100 MW in Africa.

In November 2008, SDE received a 25-year concession from a Muslim country in Africa that SDE declined to identify “upon our client’s request.” It said it has begun negotiations with global institutions for insuring the project and providing financial guarantees.

The developer said the cost of the project is US$100 million, with expected revenues from sale of electricity to be US$1 billion.

SDE said it has an international patent and other patents pending for its wave energy device. The technology employs a buoy lying atop the water, with attached hydraulic arms that transfer wave action to a generator, creating electricity. The company said it has built eight models that have operated successfully, the last of which had a capacity of 40 kW. SDE said the first commercial model has operated for a year in the port of Jaffa, Israel.


Scotland announces details of 10 million pound prize

The government of Scotland has revealed details of what it will take to win the 10 million pound (US$14.94 million) Saltire Prize for new wave or tidal power technologies. Called the world’s largest single prize for innovation in marine renewable energy, the award is to encourage world scientists to push the frontiers of innovation in clean, green energy. Entrants for the prize are to demonstrate their innovations in Scotland.

In December 2008, Scotland’s chief scientific adviser, Anne Glover, chairman of the Saltire Prize Challenge Committee, said the prize would go to the team that can demonstrate in Scottish waters a commercially viable wave or tidal energy technology that achieves a minimum continuous electrical output of 100 gigawatt-hours over two years. It is to use only the power of the sea and would be judged the best overall technology after consideration of cost, environmental sustainability, and safety.

Glover previously said the competition would open in the summer of 2009 and close by June 2013.

For information on the Saltire Prize, see the Internet site, www.scotland.gov.uk/Topics/Business-Industry/Energy/saltire-prize.


Briefly…

Scotland-based wave energy developer Pelamis Wave Power has completed a 5 million pound (US$7.7 million) funding round to support its ongoing investment in wave energy research and development. Pelamis said the additional finance will enable it to accelerate construction of the next generation of its Pelamis technology, which utilizes steel “sea-snakes” that are moored to the seabed to harness wave action for power generation. … The government of Scotland plans to significantly increase its financial support for wave and tidal energy by increasing the number of Renewable Obligation Certificates (ROC) offered to marine energy projects. Proposed changes to the Renewables Obligation (Scotland) include “banding” the program, grouping technologies into separate “bands” to receive differing amounts of support based on their stages of technological development and associated costs. … Investment manager Inspired Evolution Investment Management’s private equity clean technology fund is the first of its kind in South Africa. Evolution One Fund has raised 400 million rand (US$48.2 million) from international investors and aims to reach 1 billion rand (US$120.6 million) by July 2009. The company plans to invest in clean technology, possibly including ocean energy.


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