Renewable Energy Sources: Types and Benefits in Australia

What is Renewable Energy?

Renewable energy is energy derived from natural resources that are constantly replenished. Renewable energy technologies utilize or enable the use of one or more renewable energy sources.

Types of Renewable Energy Technologies

• Bioenergy
• Geothermal energy
• Hydropower
• Ocean energy
• Solar energy
• Wind energy

Renewable Energy Technologies: Related Systems

Renewable energy technologies also include hybrid and related technologies that:

• Store energy generated using renewable energy
• Predict renewable energy supply
• Assist in the delivery of energy generated using renewable energy technologies to energy consumers

Bioenergy: A Sustainable Energy Source

Bioenergy is a form of renewable energy derived from biomass to generate electricity and heat or to produce liquid fuels for transport. Biomass is any organic matter of recently living plant or animal origin. It is available in many forms, such as agricultural products, forestry products, and municipal and other waste.

Advanced Bioenergy Technologies

Traditionally, mainly woody biomass has been used for bioenergy. However, more recent technologies have expanded the potential resources to include agricultural residues, oilseeds, and algae. These advanced bioenergy technologies allow for the sustainable development of the bioenergy industry without competing with the traditional agricultural industry for land and resources.

Benefits of Bioenergy

Bioenergy offers the potential for considerable economic benefits, including:

• Increasing Australia's energy security
• Reducing greenhouse gas emissions
• Stimulating regional development

Geothermal Energy: Harnessing Earth's Heat

Geothermal energy is the energy stored as heat in the Earth. In Australia, this energy is abundant. There is a steady flow of heat from the center of the Earth (where temperatures are above 5000°C) through the surface of the Earth (-30 to +40°C) into space (-273°C) - heat flows from hot to cold. The heat is generated by the natural decay over millions of years of radiogenic elements, including uranium, thorium, and potassium.

Energy is brought to the surface by extracting hot water that is circulating amongst the subsurface rocks or by pumping cold water into the hot rocks and returning the heated water to the surface to drive steam turbines to produce electricity.

Geothermal energy holds the promise of being a renewable energy source that can operate 24 hours a day, providing critical large-scale baseload power for Australian homes and industries. In addition, geothermal energy can be used for heating and cooling purposes. A number of buildings, residential homes, and swimming pools currently use geothermal for these purposes.

It has only become evident in the last decade that Australia has considerable geothermal energy potential. This is partly because of a perception that geothermal resources are found only in regions of active volcanism, which excludes Australia. Although there are no active volcanoes on the continent, Australia does have substantial potential for hot rock and other resources.

Hydropower: Utilizing the Power of Water

Hydropower is a renewable source of energy that uses the force or energy of moving water to generate power. This power, or 'hydroelectricity', is generated when falling water is channeled through water turbines. The pressure of the flowing water on turbine blades rotates a shaft and drives an electrical generator, converting the motion into electrical energy.

Hydropower is the most advanced and mature renewable energy technology and provides some level of electricity generation in more than 160 countries worldwide. Hydropower plants range from very small to very large individual plants and vast integrated schemes involving multiple large hydropower plants.