Experts want to bring attention to critical silicon sustainability in solar cell production. 

UNSW researchers have conducted a wide-ranging review of global consumption trends and usage predictions of the material polysilicon used in solar cells. 

They found that there is likely to be supply pressures placed on global reserves of polysilicon as the manufacture and deployment of solar panels increases across the world, and that future deployment of low-cost PV will require close monitoring of silicon consumption to ensure polysilicon production can grow proportionately with demand without the supply issues that have been seen in the past. 

The global solar photovoltaic (PV) market has reached 1 terawatt of power output in 2022. However, to power the earth using 100 per cent renewables by 2050, as much as 60 TW will be needed from PV. 

Crystalline silicon based PV has dominated 95 per cent of the market in the last 5 years, with most electricity generation from solar PV coming from monocrystalline-silicon based passivated emitter and rear contact (PERC) solar cells.

Polysilicon is a high-purity form of silicon, which is a key raw material in the crystalline silicon photovoltaic (PV) technology. 

To produce solar modules, polysilicon is melted at high temperatures to form ingots typically using Czochralski monocrystalline, which are then sliced into wafers and processed into solar cells and assembled into solar modules. 

Last year alone, about 30 billion silicon wafers were produced for 191 GW. Considering how much more will need to be produced to meet 100 per cent renewable energy, the silicon demand will continue to increase exponentially.

In order to meet the increased demand for solar power across the world required to replace energy generated by fossil fuels, a huge increase in the production of solar panels will be needed, using up to 6-7 megatonnes (Mt) per year or cumulative amount of 46-87 Mt of polysilicon in 2050 under a broad electrification scenario. 

The experts say that this means the industry needs to immediately work towards a sustainable model of polysilicon production.

More details are accessible here.