Power from the sea: South Africa, often criticised as 'the dirty man of Africa' in terms of environmental pollution, is now determinedly going green. Tom Nevin reports on a new project which will use the power of the sea to generate electricity.South Africa's attempt to generate energy from ocean waves moved up a gear with the completion of the preliminary site evaluation and selection process for a 20MW wave energy project. [ILLUSTRATION OMITTED] [GRAPHIC OMITTED] An initial report prepared by ZLH ZLH Zigzag Leafhopper Consulting Engineers has identified two priority sites, as yet unnamed but reportedly off the Western Province coast north of Cape Town Cape Town or Capetown, city (1991 pop. 854,616), legislative capital of South Africa and capital of Western Cape, a port on the Atlantic Ocean. It was the capital of Cape Province before that province's subdivision in 1994. . The installation, delivering enough electricity to power a town of about 120,000 residents, was inspired by the Clinton Global Initiative and is being undertaken by Finavera Renewables Finavera Renewables Inc. is a publicly traded company (symbol FVR on the TSX Venture Exchange[1]) that develops and manufactures wind and wave energy projects in several countries. Finavera Renewables is developing a unique wave energy techonology called "AquaBuOy". of Vancouver, Canada. The company is developing the AquaBuoy wave energy converter for use in the US, Portugal, South Africa South Africa, Afrikaans Suid-Afrika, officially Republic of South Africa, republic (2005 est. pop. 44,344,000), 471,442 sq mi (1,221,037 sq km), S Africa. and Canada. Finavera's CEO (1) (Chief Executive Officer) The highest individual in command of an organization. Typically the president of the company, the CEO reports to the Chairman of the Board. , Jason Bak, says the initiative is aimed at reducing energy poverty in South Africa and developing a clean source of renewable energy Renewable energy utilizes natural resources such as sunlight, wind, tides and geothermal heat, which are naturally replenished. Renewable energy technologies range from solar power, wind power, and hydroelectricity to biomass and biofuels for transportation. in the country. "This project will illustrate how the developing world can mitigate climate change, help alleviate energy poverty and make a commercial return on a significant renewable ocean energy resource," says Bak. The device is a floating buoy structure that converts the kinetic energy kinetic energy: see energy. kinetic energy Form of energy that an object has by reason of its motion. The kind of motion may be translation (motion along a path from one place to another), rotation about an axis, vibration, or any combination of of the vertical motion of oncoming on·com·ing adj. Coming nearer; approaching: an oncoming storm. n. An approach; an advance. waves into electricity. It is modular and can be scaled from a small cluster of AquaBuoys to a farm of hundreds of units, providing power from a few hundred kilowatts to several hundred megawatts. The system consists of an acceleration tube rigidly mounted under the body of the buoy and open at both ends so seawater seawater Water that makes up the oceans and seas. Seawater is a complex mixture of 96.5% water, 2.5% salts, and small amounts of other substances. Much of the world's magnesium is recovered from seawater, as are large quantities of bromine. can pass freely back and forth. This forces the buoyant piston to move, extending or compressing the hose pumps. The hose-pumps are steel reinforced rubber hoses whose internal volume is reduced when the hose is stretched, thereby acting as a pump. The pressurised sea water is subsequently expelled into a high-pressure accumulator A hardware register used to hold the results or partial results of arithmetic and logical operations. (processor) accumulator - In a central processing unit, a register in which intermediate results are stored. and then to a turbine which drives a generator. The company is dedicated to the development of renewable energy resources and technologies. Power prices set to increase Several factors were taken into account when assessing potential sites. Site assessment took into account wave resource potential, distance from potential customers, distance to appropriate ocean depth, proximity to transmission lines, visual impact, and proximity to shipping lanes. The study included a political and economic analysis of South Africa, noting that power generation capacity has not kept abreast of demand, resulting in power shortages occurring recurrently in the last three years. As a result, electricity prices are anticipated to grow at an estimated 5.1% a year, creating favourable market conditions for renewable energy. [ILLUSTRATION OMITTED] More recent reports say Eskom, South Africa's electricity monopoly, has applied to the power sector's regulator for an increase in excess of 18% to underwrite the urgent need to install generation capacity from a variety of sources, including thermal, gas turbine, nuclear and a range of renewables such as ocean wave, solar, wind, geothermal and hydroelectric. South Africa must double its current output of about 40,000MW over the next 10 years to meet the demands of its economic growth. Mauritius rides the waves Meanwhile, advances in wave energy technology are encouraging enough for Mauritius to consider them seriously as an alternative means of long-term power generation. Pilot plans the government is pondering include generators coupled to floating devices or spun by air displaced by waves in hollow concrete structures. The island's electricity planners are also keeping an eye on the progress and performance of a shore-based wave power generator being tested at Port Kembla Port Kembla, Australia: see Wollongong. in Australia, capable of generating 500MW a year. In this model, the energy of waves crashing against the shore is absorbed by an air-driven generator and converted into electricity. Other sea-powered methods being considered by the Mauritians include ocean thermal energy conversion Ocean thermal energy conversion(OTEC) is a method for generating electricity which utilizes the temperature difference that exists between deep and shallow waters — within 20° of the equator in the tropics — to run a heat engine. , a relatively unproven technology that uses differences in temperature between water near the surface and deeper water. Investigations are also underway into various new methods of wind power on the islands of Mauritius, Agalea and Ridrigues, along with innovative solar technology. |
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