Turning old mines into renewable energy projects
Willow Aliento | 26 April 2017
A feasibility study for a solar pumped hydro energy storage project in Bendigo could help provide an answer to the vexing question: “What do we do with old mines once they are done with?”
The Victorian government has just announced $100,000 in funding for a study to see if the historic Goldfields mine shafts could be used to generate and store renewable electricity through the use of solar pumped hydro generation.
The City of Greater Bendigo council has also committed support of $50,000 for the research.
“Solar pumped hydro has the potential to store and generate significant amounts of energy,” Victorian energy, environment and climate change minister Lily D’Ambrosio said.
“This feasibility study is the first key step towards realising the benefits of solar pumped hydro for the Bendigo region.”
Ms D’Ambrosio said initial research suggested such a facility could generate enough power in an hour to power 160 homes (784 kilowatt-hours).
It would also be able to provide around-the-clock supply, boosting the reliability of the local grid and making the city a net exporter of energy.
Pumped up about pumped storage
According to 2014 research by Arup and the Melbourne Energy Institute, pumped hydroelectricity energy storage is the most significant form of large-scale energy storage globally.
At the time of preparing the report, there was 197 gigawatts of installed capacity – amounting to more than 99 per cent of electrical energy storage capacity globally.
Examples include Dinorwig Power Station at Elidir Mountain, also known as Electric Mountain in Snowdonia National Park in Wales. The installation was commissioned in 1984 and can store around nine gigawatt-hours of electricity. It is still one of the largest pumped hydro power stations in Europe.
Dinorwig Power StationConstructed in an old slate quarry, an output of 1728 megawatts can be achieved from a standing start within 16 seconds. A gas-fired plant by comparison takes a few minutes to start outputting power, a coal-fired plant takes hours, and a nuclear plant takes even longer.
GE Renewable Energy recently delivered Linthal in Switzerland – a pumped hydropower station capable of an output of 1450MW when all four of the motor-generators come online. That is enough to supply one million Swiss homes at peak power.
Australia’s three largest installations are Tumut 6 – part of the Snowy Mountains Hydro Scheme and commissioned in 1973 – the 240MW Shoalhaven plant facility commissioned in 1977 and the 500MW Wivenhoe facility commissioned in 1984.
In total, Australia had around 1490MW of pumped hydropower storage in operation in 2010.
There is already a new project on the drawing boards that combines solar and pumped storage in North Queensland. The project is being developed on the site of one of Australia’s largest open cut gold mines, which closed in 2001.
Genex Power’s Kidston Solar Farm Project, being planned in two stages, will utilise the remaining mine infrastructure, including the dams and roads. The first stage of 50MW of solar will feed into the National Electricity Market directly.
The second stage’s 270MW solar installation will be used to power the pumping element of the proposed Kidston Pumped Storage Hydro project.
The company expects the hydro storage will have a generation capacity of 250MW, with the potential to operate over a continuous six-hour generation cycle, resulting in 1500MWh of renewable energy.