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The Australian Antarctic Division (AAD) received a grant of half a million dollars from the Australian Greenhouse Office to demonstrate the use of hydrogen generated by wind in Antarctica. The demonstration project at the remote Mawson site will research the safety and operational aspects of using hydrogen on station, as well as its viability as a major energy carrier.

Hydrogen is not, as many people believe, an energy source. Neither is electricity. In contemporary energy systems, electricity serves as an energy carrier. It is produced from primary energy sources using technology such as diesel powered generators or wind turbines. It is the same case with hydrogen.

Hydrogen will be generated using energy from the Mawson station’s wind turbines, stored and used in a test fuel cell, as fuel in a heater and in one of the station vehicles. Two Enercon wind turbines, capable of withstanding blizzards in excess of 300 km/h, were recently installed. Together, the units provide one MW of electricity for use at the research station and for the hydrogen project — and dramatically lower the need for imported diesel fuel.

“The Mawson system will generate well over ten times the power of existing Antarctic wind-power systems while having a much lower environmental impact than the current option of diesel fuel now used throughout Antarctica,” said Australia’s Environment Minister Robert Hill, regarding the wind turbine construction. “When the system is fully developed, an Antarctic station will, for the first time, be able to use a renewable source to meet virtually all its energy needs.”

For the upcoming hydrogen demonstration project, the AAD plans to install the test fuel cell and heater at the field camp on Bechervaise Island. They will provide electricity and heat for the scientists involved in the penguin monitoring program.

By the completion of the project, the staff at AAD expects to gain sufficient information to be able to model the large-scale use of hydrogen to supplement their energy requirements.

Hydrogen used by the Bureau of Meteorology staff for daily weather balloon flights is currently generated on site. Electrolyzers, powered in part by wind energy, produce hydrogen from water. Any excess hydrogen produced will be stored and utilized for the project. The system will be installed and implemented during the 2005-06 season.

The AAD expects that the use of hydrogen as a fuel will reduce the need for fossil fuels during those times when the wind energy is insufficient to power the station. The hydrogen will fuel either a large-scale fuel cell system or an internal combustion engine generator.

The ultimate aim is to be able to run the station and all the field camps without the use of any fossil fuels. The AAD believes this may be the first attempt to use hydrogen as a major energy source in Antarctica.

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Tidal power is the only form of energy which derives directly from the relative motions of the Earth–Moon system, and to a lesser extent from the Earth–Sun system. The tidal forces produced by the Moon and Sun, in combination with Earth’s rotation, are responsible for the generation of the tides. Other sources of energy originate directly or indirectly from the Sun, including fossil fuels, conventional hydroelectric, wind, biofuels, wave power and solar. Nuclear is derived using radioactive material from the Earth, geothermal power uses the heat of magma below the Earth’s crust, which comes from radioactive decay.
Variation of tides over a day

Tidal energy is generated by the relative motion of the Earth, Sun and the Moon, which interact via gravitational forces. Periodic changes of water levels, and associated tidal currents, are due to the gravitational attraction by the Sun and Moon. The magnitude of the tide at a location is the result of the changing positions of the Moon and Sun relative to the Earth, the effects of Earth rotation, and the local shape of the sea floor and coastlines.

Because the Earth’s tides are caused by the tidal forces due to gravitational interaction with the Moon and Sun, and the Earth’s rotation, tidal power is practically inexhaustible and classified as a renewable energy source.

A tidal energy generator uses this phenomenon to generate energy. The stronger the tide, either in water level height or tidal current velocities, the greater the potential for tidal energy generation.

Tidal movement causes a continual loss of mechanical energy in the Earth–Moon system due to pumping of water through the natural restrictions around coastlines, and due to viscous dissipation at the seabed and in turbulence. This loss of energy has caused the rotation of the Earth to slow in the 4.5 billion years since formation. During the last 620 million years the period of rotation has increased from 21.9 hours to the 24 hours[3] we see now; in this period the Earth has lost 17% of its rotational energy. While tidal power may take additional energy from the system, increasing the rate of slowdown, the effect would be noticable over millions of years only, thus being negligable.

Types of Tidal Energy
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Tidal power can be classified into two main types:

* Tidal stream systems make use of the kinetic energy of moving water to power turbines, in a similar way to windmills that use moving air. This method is gaining in popularity because of the lower cost and lower ecological impact compared to barrages.

* Barrages make use of the potential energy in the difference in height (or head) between high and low tides. Barrages are essentially dams across the full width of a tidal estuary, and suffer from very high civil infrastructure costs, a worldwide shortage of viable sites, and environmental issues.

* Tidal lagoons, are similar to barrages, but can be constructed as self contained structures, not fully across an estuary, and are claimed to incur much lower cost and impact overall. Furthermore they can be configured to generate continuously which is not the case with barrages.

Modern advances in turbine technology may eventually see large amounts of power generated from the ocean, especially tidal currents using the tidal stream designs but also from the major thermal current systems such as the Gulf Stream, which is covered by the more general term marine current power. Tidal stream turbines may be arrayed in high-velocity areas where natural tidal current flows are concentrated such as the west and east coasts of Canada, the Strait of Gibraltar, the Bosporus, and numerous sites in south east Asia and Australia. Such flows occur almost anywhere where there are entrances to bays and rivers, or between land masses where water currents are concentrated.