Solar energy may be the future. But only if it lets go of the past.
International NGO the World Economic Forum has issued a damning report card on the state of the world’s solar panel manufacturing. It may be experiencing rapid growth. It may be one of the cheapest sources of power. But its climate credentials face intense scrutiny.
Forced labour, coal-fuelled production processes and a lack of transparency around the source of crucial components combine, the WEF says, into a cause for concern.
“The solar industry is currently grappling with supply chain issues that could significantly impact its future,” the authors, professors Morgan Bazilian and Dustin Mulvaney, write.
Much of their concern is concentrated on the production of polysilicon and the drive to make it cheap.
Some 45% of global production of this component is sourced from Xinjiang province in China. And much of the labour force used to produce it is supplied by “re-education camps” detaining ethnic Kazakhs and Kyrgyz.
On top of that, the remote desert region relies heavily on locally sourced coal for its power supply. “This attracted polysilicon manufacturers to this region of China in the first place because electricity is a major cost in the production process,” the report reads.
This, they say, undermines any climate and environmental benefits offered by solar panels further down the supply chain.
“Solar panels are cheaper to build and install today in many places than alternative sources of electricity like coal and natural gas, translating to lower levels of greenhouse gases and air pollution,” they write.
But Professor Alistair Sproul of the ANU’s School of Photovoltaic & Renewable Energy Engineering says photovoltaic power has more than enough wiggle room in its pricing to clean up its act. Much of the price drop in photovoltaic (PV) production in recent years has been driven by advances in technology, particularly crystalline silicon, he says. “Even if the price stayed where it is now or went up a little – PV is very cost-competitive.”
Under current life-cycle calculations, crystalline silicon PV cells produce about 50g of CO2 for every kilowatt-hour of electricity. Black coal, in comparison, comes in at 1000g of CO2 per kWh.
“The PV industry is growing each decade or so by a factor of 10 – this next decade is crucial – but as scale increases, costs will come down anyway – and the industry is not reliant on forced labour,” says Sproul.
“Low-cost energy is really key here – so that there is a virtuous cycle – that as PV itself becomes cheaper it should be possible to lower the cost of producing PV further by utilising increasing amounts of PV electricity in manufacturing.”
Sproul says materials that need coal for processing – especially steel – are all seeking alternatives. “Hydrogen is definitely an avenue worth exploring as an alternative to coal to reduce iron oxide (for steel) and silicon dioxide ( for silicon). [And] all supply chains need to be clear, transparent and free from forced labour.”