The sun sets behind a pair of transmission pylons carrying high voltage power cables in Sydney December 7, 2009. Reuters/Tim Wimborne

Australia can construct a secure and inexpensive energy grid that will use 100 percent renewable energy, according to the findings of a new research conducted by the Australia National University (ANU). Moreover, the new grid can be created using existing technologies.

The electricity grid will depend on wind and solar technology, aided by pumped hydro storage. The study has found not only will the project be inexpensive, it will remove the requirement of coal and gas-fired power. The grid can be set up with “off the shelf” products.

The power supplied through the grid would cost $75 per megawatt hour in 2020. This, the university said, would be more inexpensive than coal and gas. According to the findings of the new modelling released by the Federal Government, prices for South Australia businesses have upped by more than 100 percent in the last 10 years, AM reports.

"With Australia wrestling with how to secure its energy supply, we've found we can make the switch to affordable and reliable clean power," Professor Blakers, from the ANU Research School of Engineering, said. Only 15 percent of Australia’s electricity generation comes from renewable energy. Meanwhile, almost two-thirds of the nation’s power comes from coal-fired power stations. "However, most existing coal and gas stations will retire over the next 15 years, and it will be cheaper to replace them with wind and solar PV," Blakers added.

The new research involves studying the advantages of hydro power energy storage. The water will be driven uphill where it will be stored to generate power on demand. "Pumped hydro energy storage is 97 per cent of all storage worldwide, and can be used to support high levels of solar PV and wind," Blakers said.

According to 2016 findings, wind cost $65 per megawatt hour last year. The cost of the same was projected to drop to $50 per megawatt hour in the 2020s. Meanwhile, the cost of the solar was $79 per megawatt hour in 2016 and was projected to decrease to $50 per megawatt hour in the 2020s.

The cost of the power grid, at 2016 prices, was estimated at $93 per megawatt hour. On the other hand, at 2020 prices, the cost slid down to $75 per megawatt hour. An extra $25 per megawatt hour would account for storage using pumped hydro, energy losses and the cost of new interconnectors.

ANU is currently involved in mapping out potential short-term off-river pumped hydro energy storage (STORES) sites. These sites, as noted by Blakers, required less water than power generated by fossil fuels. Moreover, they do not have adverse effects on the environment.

"This hydro power doesn't need a river and can go from zero to full power in minutes, providing an effective method to stabilise the grid," he said. "The water is pumped up from the low reservoir to the high reservoir when the sun shines and wind blows and electricity is abundant, and then the water can run down through the turbine at night and when electricity is expensive."