Your Questions About Wind Turbine Generators Australia

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Geothermal power is power extracted from heat stored in the earth and comes from radioactive decay of minerals and from solar energy absorbed at the surface. It’s used to heat up baths and for generating electricity. Geothermal power is cost effective, reliable, and environmentally friendly, but has previously been geographically limited to areas near tectonic plate boundaries.Geothermal wells tend to release greenhouse gases trapped deep within the earth, but these emissions are much lower than those of conventional fossil fuels. As a result, geothermal power has the potential to help mitigate global warming if widely deployed instead of fossil fuels. As of 2004, five countries (El Salvador, Kenya, the Philippines, Iceland, and Costa Rica) generate more than 15% of their electricity from geothermal sources.

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It’s a big piece, but I hope you get all the info u need =)

1. The process of harnessing energy from the ocean’s tide is very similar to that of harnessing water through a hydroelectric dam. However, the dam needed for this process is much larger. Installed within the dam are turbines. The movement and flow of the tide in and out from the shore is then used to turn those turbines and create the power needed.

(2,3,4 question) There are two ways at present of using tidal power:

Barrage systems: This system, built like a dam across a river, holds back the water till the tide has gone out, then uses the potential energy of the water to turn turbines in the barrage. This is an expensive system with many disadvantages.

Tidal Stream systems. This consists of using turbines, rather like wind turbines, to use the kinetic power of the moving water to generate electricity. This is easier and cheaper to install.

There are three Barrage systems operating throughout the world.

One large 240 MW plant on the Rance River in France, and two small plants,

one in the Bay of Fundy in Canada, and

another in Kislaya Guba in Russia.
There is only one Tidal Stream system working commercially:

A fullsize turbine prototype, SeaGen, was installed in Strangford Lough in Northern Ireland in 2008, with a capacity of 1.2 MW.
A large number of smaller tidal stream pilot schemes are being trialled.

-In Hammerfest, Norway a turbine, generating 300 kW, started in 2003.
-A 300 kW Periodflow marine current propeller type turbine was tested in Devon, England in 2003.
-Since April 2007 a prototype project in the East River in New York City has been running.
-An Open-Centre Turbine, has a prototype being tested at the European Marine Energy Centre (EMEC), in Orkney, Scotland.
-A Gorlov turbine, an improved helical design, is being prototyped on a large scale in S. Korea.
-Neptune Renewable Energy has developed Proteus which uses a barrage of vertical axis crossflow turbines for use mainly in estuaries.
-During 2003 a 150kW oscillating hydroplane device, the Stingray, was tested off the Scottish coast.
-Successful commercial trials of highly efficient shrouded tidal turbines on the Gold Coast, Queensland, Australia in 2002.
-Shrouded turbines are being installed for a remote Australian community in northern Australia, two small turbines will provide 3.5 MW.
-Another larger 5 meter diameter turbine, capable of 800 kW in 4 m/s of flow, is planned as a tidal powered desalination showcase near Brisbane Australia in October 2008.
-The Hydro Venturi, is being tested in San Francisco Bay.
-In April 2008, a turbine-generator unit (TGU) prototype was successfully tested at Cobscook Bay and Western Passage tidal sites near Eastport, Maine.
-Trials in the Strait of Messina, Italy, started in 2001 of the Kobold concept.

(4,6,7) Tidal energy use harnesses the water flow created primarily by the moon orbiting the Earth. As water is pulled toward the gravity of the moon, currents are created that can turn generator turbines.

Volumes have been written about tides and their effects on our planet. This Wikipedia Tides article is a good primer on the subject. It is noteworthy that all tidal energy does not come from the moon. About a third of it comes from the gravitational influence of our sun.

The interplay of gravitational fields of the moon and the sun combined with the rotation of Earth, creates a twice a day ebb and flow of the tides of our world that varies in height and strength.

Those variations in height and strength are completely predictable. As we’ll see later, that predictability is an important aspect of tidal energy use.

Though renewable, practical tidal energy use will be limited. Tidal flows are global, but the key to using them economically is finding either natural high tidal flow areas, or large tidal basins that can be easily dammed to channel water through turbines. _________________________________________________________________

ENVIRONMENTAL FRIENDLINESS –

Tidal energy use involving dams creates many of the same environmental concerns as damming rivers. Tidal dams restrict fish migration and cause silt build up which affects tidal basin ecosystems in negative ways.

Systems that take advantage of natural narrow channels with high tidal flow rates have less negative environmental impact than dammed systems. But they are not without environmental problems.

Both systems use turbines that can cause fish kills. But these are being replaced by new, more fish friendly turbines. The art and science of environmentally friendly hydro engineering is well advanced and will certainly be applied to any tidal energy project.

But even with dams, the environmental impact of tidal energy projects may prove to be smaller than our use of any other energy resource. Economics will severely limit the number of tidal energy projects. ______________