Renewable energy

Why can't we just use renewable energy such as solar or wind to meet all our electricity demands?

This is a very complex issue and there are many different factors at play.

Developments in technologies have brought a range of options for energy generation from resources which are renewable. These include:

• hydro power
• biomass
• wind power
• solar power (photovoltaics and solar thermal)
• ocean energy
• tidal power
• geothermal.

See further information about renewable energy in the glossary.

Infrastructure

We know that renewable energies are able to supply some of our power needs, but our existing power grids across Australia (the power lines and power base stations which deliver electricity) are not set up to deliver the required amount of power on a continuous reliable basis from the many and varied locations from where renewable energies can currently be captured.

The costs of infrastructure upgrades to increase the supply of electricity from renewable sources have not been estimated in Australia. In Britain, however, one study estimated that ₤4.7 billion is required to upgrade Britain's electricity grid by 2020, to accommodate new power generation, including renewables and nuclear plants. This cost includes high voltage sub-sea cable links between Scotland and England.¹

In Australia, transmission networks are geared to handle increments of power supply that:

• are near an established grid;
• have consistent supply;
• are on a large scale;
• are highly centralised.

Newer renewable technologies generally:

• are further from the grid (geothermal, thermal solar and wind);
• have intermittent supply (wind and solar);
• operate on a smaller scale (tidal);
• are decentralised or embedded (photovoltaic solar and biomass).

Without major changes in the transmission infrastructure, new technologies will find it difficult to compete commercially.²

Current situation in Australia

Transmission lines and generators in Australia, 2009
Source: ABARE http://www.abareconomics.com/publications_html/energy/energy_09/auEnergy09.pdf

Currently around Australia there are more than 600 operating renewable energy generators contributing power to Australia's energy requirements.³ View the map showing the locations where different types of energy generation takes place at http://www.ga.gov.au/renewable/.

When people talk about power supply from fossil fuels or renewable energies, there is always discussion about power demands and supply. Fossil fuel power is believed to deliver the most reliable, cost-effective and continuous source of electricity, yet this is due to how we have set up our infrastructure.

Different sources of renewable energy can differ in their reliability of supplying power. Reliability is related to how the power is generated, for example the wind must be blowing or the sun must be shining to generate wind or solar power. The ability to store energy created by renewables for later use is also a problem and more research and investment is needed before more power from renewables could be put into action.

Using a combination of renewable energies would seem to be the solution, as technologies such as biomass, waves and hot fractured rock are capable of delivering reliable and continuous energy.⁴ Other sources such as wind and solar power can contribute effectively by contributing power during periods of intermediate and peak demand. Renewables can also be the solution to providing power in remote areas, where the cost of fossil-fuel-delivered power can be expensive.

Before more renewable energy can be used for our everyday activities, investment and extensions to the current energy distribution grid has to occur, along with technical advances to provide a way to store the energy produced, and all in an affordable way for us as consumers.

Return to Adaptations to reduce greenhouse emissions

¹Transmission and Distribution 2009. Australasian Power Technologies Issue 3: p.29 June 2009

²Garnaut R, 2008, The Garnaut Climate Change Review: Final Report Commonwealth of Australia, Cambridge University Press, Port Melbourne. www.garnautreview.org.au

³Geoscience Australia, http://www.ga.gov.au/renewable/, site visited 5 March 2009.

⁴Needham S, 2008, Parliamentary Library Research Paper, 'The potential for renewable energy to provide baseload power in Australia', Parliament of Australia. Source: http://www.aph.gov.au/library/pubs/rp/2008-09/09rp09.htm