The economic benefit of Si recovery

The direct impact of the Si recovery technology on the PV value chain is that a large part of the value from the wafer sawing waste can be recovered. As a result, the efficiency to use PV-grade Si as feed-stock for PV module production will be greatly increased. Moreover, the emissions of CO2, SOx, NOx etc will be greatly reduced as a result of partly avoided energy intensive traditional Si purification processes.

As a more detailed example, for a PV producer of middle-high wafer production volume of 1.5GW PV module production line, the yearly Si consumption is about 8’250t, including a sawing loss of 3’300t (@40% loss). With a technology to recover 80% of the kerf-loss, 2640t of PV grade Si, with a market value of 40M$ (@15$/kg) can be recovered. With a possible recovery cost of <8$/kg, a net cost reduction of 18.5M$ would be realized from saving the Si.

Integrated PV module producers based on diamond wire sawing technologies will profit mostly from the Silicon kerf recycling technology. These clients profit from the low cost of recovered Si to be re-introduced into the production. Thus, they can either reduce their dependence on Si feedstock providers and will become more cost-competitive on the market. Or, for the integrated producers who manufacture their own PV-Si feedstock at a Capex of about 65$/kg of annual Si production capacity, they profit from a significant advantage to delay the investment into new Si production capacities for several years, leading to a delay in the cash expense, which is critical in PV industry.