Switching off lights and appliances for one hour in itself will make little difference but Earth Hour will make an impact through energy customer awareness and action, says a Queensland University of Technology energy expert.
Professor Gerard Ledwich from Queensland University of Technology's School of Engineering Systems said the public's engagement with Earth Hour would increase awareness of how their behaviour could have a significant impact on the future of the planet.
"Earth Hour focuses people's attention on how their use of appliances and general lifestyle choices - such as turning lights off and choosing how much to use air conditioners - affect the environment," Professor Ledwich said.
"We are moving to a phase where how people respond to lowering their energy usage and adopting renewable energy will be vitally important to reducing greenhouse gases.
"We would not expect people to install a wind meter and turn power off but rather sign up to an automated program which would control timing of swimming pool pump operation and shift heavy usage of items such as dryers to times with a strong supply of energy.
"If energy consumers learn to adjust their energy usage so that peak load times had a greater spread, we would be better able to achieve a 20 per cent emissions reduction through the use of wind and solar energy.
"This is because renewable energy sources such as solar and wind will have greater variation and would require greater customer responsiveness to manage."
Professor Ledwich said the energy sector would, in the near future, look for ways to partner with energy customers to modify their load without a huge impact on their lifestyles.
"This will be an important dimension to achieve greater renewable energy absorption into our total energy supply mix," he said.
Explore further: What's wiping out the Caribbean corals?