Nctce Logo White Mono Cropped

1 - 2 November 2021
BCEC, Brisbane


What is sustainable energy?

Original 1120037774

What is sustainable energy?

Sustainability, according to the United Nations’ Brundtland Commission of 1987, is the ability of systems to meet the needs of current society without affecting the ability of future generations to meet their needs. In line with this definition, sustainable energy is the energy that powers the needs of the current generations but maintains the ability to meet those of future generations.

Sustainable energy is part of the planet’s structure which implies it is replenished constantly via natural means. To put it differently; sustainable energy simply cannot run out.

Sustainable energy is often referred to as “alternative energy” because it is the better option to traditional fossil fuel like coal and oil.

At this point, it is important to understand that the term sustainable energy should not be construed to mean that it is 100% environmentally safe. For example, dams harness the energy of moving water which can harm wildlife such as fish. However, renewable energy sources have a very light environmental footprint compared to fossil fuels. It is because of this that sustainable energy is the global ticket to a cleaner and less polluted earth.

Here, it is important to ask the main question: “How does sustainable energy work?” This is a closer look at the main sources of clean and sustainable energy sources that individuals, corporations, and governments can tap into to drive sustainable economies.


Green and Clean: The Main Sustainable Energy Sources

The four main types of alternative energy sources are harnessed from natural processes such as water, wind, and sunlight. They are the most sustainable forms of energy.


1. Solar Energy

Sunlight is one of the main renewable sources of energy we know of today. To harness solar energy, a number of technologies are used to help convert it into heat, electricity, or light.

  • Photovoltaic systems are used to convert sunlight into electricity.
  • Solar water heating system are used to heat buildings.
  • Mirrored dishes help to boil water in conventional steam systems to generate electricity.

In commercial buildings, solar energy is used to promote processes such as heating, cooling, and ventilation. Homeowners can also take advantage of solar power by installing solar systems that help heat water, run appliances, and light their premises.  


2. Wind Energy

Wind can be indirectly considered part of the solar power because it comes from uneven heating and cooling of the atmosphere resulting in winds. It is also caused by regular rotation of the earth. To harness wind power, green power companies use a wind turbine that rotates generators to generate electricity.

Today, there are many commercial grade wind-power generating systems designed to meet the energy requirements of different users. For example, a single wind turbine can be used to generate electricity for individual homes and small enterprises.

To generate electricity on a large scale from wind power, companies and governments have to invest in large scale wind farms. These are multiple turbines installed in areas with strong winds to generate optimal electricity that is injected into national grids or used in a specific region. A good example is the Macarthur Wind Farm in Victoria, the largest in Australia, with a capacity of 420 MW.


3. Geothermal Energy  

Geothermal energy is harnessed using heat generated from deep inside the earth. The heat is sourced from heated rocks near the surface or steams of hot water from miles below the surface.

The energy is harvested using geothermal power plants. These plants use the high pressure and temperature steam to run generators that produce electricity. On a smaller scale, geothermal energy can be used to heat manufacturing plants, offices or homes.


4. Hydropower

This is not a new invention. Initially, water energy was harnessed via waterwheels that used to run machines such as flour mills and sawmills. Today, the kinetic energy of flowing water is converted to electricity using special turbines.

In many cases, the water is held in a reservoir such as a dam and directed to run the turbines to generate hydroelectricity. Some of the top hydro systems in the world include the Three Gorges Dam in Hubei that generates 22,500 MW and Grand Coulee Dam in the US that emits 6,809 MW.

Snowy Hydro in Australia consists of 9 major power station, 33 turbines and a total generating capacity of 4100 megawatts (MW).  They produce on average, 4500 gigawatt-hours of clean renewable electricity each year, to meet peak power demand. The government has recently approved a significant expansion of the scheme to increase this output by 50 per cent.


5. Other sustainable energy sources

Other top sustainable energy sources that you can use include ocean thermal energy harnessed from the sun’s heat on the surface of the water, and mechanical energy from wave movement in the ocean.

Bio-energy is another sustainable source of energy that is derived from biomass to generate heat and electricity. Although bio-energy generates carbon dioxide just like fossil fuels, it is considered a cleaner option because vegetation planted to supply more biomass help to remove an equal amount of carbon dioxide from the air. This helps to keep the environmental impact neutral.


Protection of the ecosystem

Sustainable energy or clean energy is the alternative that we need. Indeed, the world does not have another option but to adopt sustainable energy because it comes with many benefits such as better health and protection of our ecosystem.

Remember that you or your business do not have to wait until your government or city management brings clean energy to you. You can start right away by acquiring solar panels or single wind turbines to help supplement or replace the current fossil fuel powered electricity.


About the Australian Cleantech sector

The future of Australian Cleantech sector largely depends on its ability to link with decision makers and investors to bring about measurable influence and mobilise its own growth.

The aim of the National Clean Technologies Conference is to highlight all Cleantech growth areas including waste, water, energy, transport and built environment.

The conference will also attract stakeholders from across the Cleantech industry to initiate growth, revolution, and investment.   

For more information or to register to attend visit or subscribe for updates.


  1. Phil Payne on June 20, 2020 at 2:05 am

    I just watched Michael Moore’s ‘Planet of the Humans’…….and I’m shocked by capitalism and environmentalists connection to it.
    Do we simply not care about forests & animals?
    Are we simply so greedy that sustainable energy is being overlooked altogether? and so we are overlooking our own species ability to live on?
    Why do we not have empathy for the life that this great planet has given us?
    Why do we take money from capitalists or their companies that seems to show no bounds to more and more profit for themselves at the expense of the only living planet in the universe?
    Why do we ignore ‘the elephant in the room’……population growth?
    What do I tell my children to tell their children?

  2. zion on February 23, 2021 at 7:19 pm

    This is so cool and fun

Leave a Comment