Australasian Science: Australia's authority on science since 1938

Keeping All the Lights On

By Ian Lowe

A 100% renewable energy system using pumped hydro can store enough power for peak demand at a competitive price to fossil fuels.

A new study by researchers at the Australian National University has found that pumped hydroelectricity is the key to a cost-effective power system providing 100% renewable energy for the so-called national electricity market, which includes Queensland, NSW, Victoria, Tasmania, South Australia and the ACT. Prof Andrew Blakers and his team were funded by the Australian Renewable Energy Agency to model the system using only technologies that are in large-scale commercial operation. This restricted the choice to solar photovoltaics (PV), wind and pumped hydro, leaving aside such options as solar thermal, battery storage and geothermal energy. The modelling showed that 50–80 pumped hydro systems, adding up to 15–20 GW of capacity, would provide enough storage to smooth out fluctuations in available wind and solar energy.

Most significantly, the study found that the cost of power from such a 100% renewable grid would be about $90/MWh based on current prices for those technologies. For comparison, the pooled price in the national electricity market now averages about $60/MWh, while it is estimated that a new black coal power station would produce electricity at a cost of about $80/MWh with no carbon price. Therefore, Blakers said, “a 100% renewable PV and wind system matches the price of a new fossil-fuel system”. That is very encouraging news, with evidence growing of the need for a rapid transition away from coal.

While the scale of construction of dams for pumped hydro appears formidable, Blakers argues that they would mostly be 10–100 ha in area, in pairs at the top and bottom of steep hills. “The amount of water required is trivial,” he said, calculating it would be about 0.1% of current annual extractions from the Murray–Darling Basin.


Two recent reports have raised similar issues about Australian public policy. The long-awaited National Science Statement, released in March, stated four objectives:

  • engaging all Australians with science;
  • building scientific skills;
  • producing new research and technology; and
  • improving Australians’ lives through research.

Most reactions were cautiously positive about the general sentiments, but negatively cautious about the probability of concerted action or serious funding. The Australian Academy of Science called it an important document providing “much needed long-term direction and purpose for government activities in regards to science”.

However, Prof Ken Baldwin of The Australian National University noted that the Statement contained no significant new strategies or funding. He called for incentives to encourage industry to collaborate with researchers.

Several observers commented that the sentiments and broad aims of the Statement are laudable, but the real test will be whether they are translated into action. As Prof. Peter Andrews, former Queensland Chief Scientist, put it most bluntly: “All we need now is for the government and the opposition to agree on this or any other policy for long enough to make a difference”.

Also in March, the fifth independent report on the state of the environment came out. Like all the previous reports stretching back to 1996, it found some good news to report. As one example, the combination of the Murray–Darling Plan and some welcome rainfall has gone some way toward restoring the health of our largest river system, despite continuing wasteful use of irrigation water in NSW and Victoria.

Also like the previous reports, the 2017 document said that we have fundamental problems. Specifically, it noted that the government does not have “an overarching national policy that establishes a clear vision for the protection and sustainable management of Australia’s environment to the year 2050”. The report called for three priorities:

  • “specific action programs and policy to preserve and, where necessary, restore natural capital and our unique environments, taking into account the need to adapt to climate change;
  • “complementary policy and strengthened legislative frameworks at the national, state and territory levels; and
  • “efficient, collaborative and complementary planning and decision-making processes across all levels of government, with clear lines of accountability”.

As with the National Science Statement, the real challenge for governments is translating the general principles and worthy aims into concrete actions that would make a difference. With the Turnbull administration appearing to lurch from one opinion poll to the next, it’s hard to be optimistic.


Ian Lowe is Emeritus Professor of science, technology and society at Griffith University.