Solar photovoltaic systems and wind turbines have been criticised for their intermittent energy generation, which limits their use as stand-alone energy sources. To account for this variability, utilities normally rely on natural gas turbines or hydroelectric turbines, both of which have a very fast response to fluctuations in energy supply and consumption.
However, battery arrays have continued to decrease in price, and they are becoming a viable complement for solar farms and wind turbines. Microgrid projects that combine renewable energy and battery storage are being used in West Australia by mining company GMA Garnet and the Australian military, and Queensland will have the first utility-scale system of this type in the world.
Scheduled for completion by the end of 2018, the Kennedy Park will have a rated capacity of 60 megawatts. The project will have 12 wind turbines rated at 3.6 MW each, and a 15-MW solar photovoltaic array with adjustable tilt angle to maximise energy output. The site has excellent wind and solar resources, which will ensure a consistent energy output. In addition, a 2-MW battery with a synchronous condenser will provide power output stabilisation.
The energy output from the hybrid 60-MW solar and wind farm will be purchased by CS Energy, a government-owned energy generation company, through a Power Purchase Agreement with a total contract amount of $160 million. In addition, the Australian Renewable Energy Agency (ARENA) will provide $18 million in grant funding for project development, and the Clean Energy Finance Corporation (CEFC) will provide a loan of up to $93.5 million.
The expected generation from the Kennedy Park is 210,000 megawatt-hours per year, which is enough to meet the energy needs of more than 35,000 Australian households. A second phase called Big Kennedy is planned for 2019, and it is a much more ambitious project: the planned capacity is 1,200 MW of combined solar and wind power, with a project budget above $2 billion.
Northern Queensland has suffered from a lack of local generation, which means energy must be transmitted from far away, driving up its cost: consider that network operation accounts for half of your power bill Australia.
There are many reasons why battery storage makes sense in Australia, and this applies for both large-scale battery arrays and smaller residential and commercial systems. Australia has an abundance of solar and wind resources, and batteries offer a solution to manage the intermittent energy output of photovoltaic panels and wind turbines. In addition, batteries simplify power network management: energy can be stored strategically to minimise the transmission and distribution burden.
In the case of homes and businesses, batteries allow a higher use of local renewable generation, absorbing surplus energy for later use. Electricity is unlikely to become cheaper in Australia in the near future, while solar panels and batteries become more affordable – they are among the preferred energy sources for Australians.