Australia has the world's highest uptake of home solar energy, with the large shiny panels a familiar sight on rooftops across the country.
More than two million households have installed rooftop solar systems - over a fifth of all homes.
The solar panels, often subsidised by state governments, have helped cut carbon emissions and reduced the need for coal-fired power while allowing homeowners to lower their energy costs.
Households can sell excess solar energy back to the electricity grid or store it in batteries. The average power saving per house is believed to be about A$540 (S$514) a year.
The rollout has continued at a frenetic rate, with an average of six panels installed per minute around the country. But the boom has led to growing concerns about how to dispose of all these panels and batteries when their life ends.
Experts say Canberra needs to quickly address the problem, especially since China last year stopped accepting recycling waste from Australia and some other countries.
The panels, made mostly of glass, can contain potentially hazardous materials such as lead and cadmium which can leak into the soil and groundwater if they are buried in landfill.
Three experts at Griffith University, Professor Rodney Stewart, Mr Hengky Salim and Dr Oz Sahin, have called on Australia to develop the ability to recycle solar panels and batteries. In addition, they said, businesses and importers should be required to source systems that are designed to be reused or recycled.
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Number of households in Australia that have installed rooftop solar systems - more than a fifth of all homes. The panels, often subsidised by state governments, have helped cut carbon emissions and reduced the need for coal-fired power while allowing homeowners to lower energy costs.
"Even if China were to suddenly start accepting Australia's waste again - an unlikely proposition - we cannot simply export our problem," they wrote on The Conversation website on June 17. "If not addressed, ageing solar panels and batteries will create a mountain of hazardous waste for Australia over the coming decades."
Australia's hot and dry climate is particularly suited to solar energy production. Most home panels last 20 to 30 years, and some are already reaching the end of their shelf life. By 2047, Australia is expected to have about 800,000 tonnes of solar panel waste.
Much of the solar waste is said to be destined for the landfill. South Australia-based firm Reclaim PV, believed to be the first dedicated recycler of panels, said in March it was recycling about 40,000 a year.
Some states have begun to take action. Victoria this week began a ban on sending solar panel materials to the landfill. This is part of a larger scheme for electronic-waste products. It bars households from throwing away products such as phones, TVs, kitchen appliances and laptops in standard bins. Instead, these items must be left at dedicated drop-off points.
The aim is to ensure such waste is reused. "E-waste contains valuable materials that we can recover and reuse, but if left in the wrong place, they can also harm the environment and human health," said Environment Minister Lily D'Ambrosio last month.
State and federal governments are also looking to develop a national plan to encourage producers, retailers and consumers to recycle, reuse or safely dispose of solar panel components. The plan is expected to be in place by next year.
Most solar panels should last decades, but there are concerns that Australia's installation rush has led to some low-quality products or poor fitting.
The concerns have not slowed the rate of installations, with official data showing that the uptake of panels continues to grow.
A recent report said more than half of Western Australia households will have solar panels within a decade. This growth in home-generated energy is set to lead to the state's first drop in demand for electricity consumed from the grid, despite a rising population.