German research institute Fraunhofer ISE believes silicon solar PV modules produced in European Union (EU) come with 40% less CO2 produced per kWh during the manufacturing process, with PV electricity compared to those produced in China.
Researchers attribute this mainly to the energy mix of respective nations, rather than to the emissions generated during the transportation process since the bulk of CO2 footprint of a solar module comes from 50% to 63% of electricity needed to produce it. In comparison, a PV module travelling from a facility in China to the EU would account for 3% of total emissions.
Additionally, a study on the subject by the team also found 7.5% to 12.5% additional emissions reduction for glass-glass modules, compared to those with backsheet films, irrespective of their manufacturing location. This is because glass-glass modules do not require energy intensive aluminium frame.
Glass-glass modules have a longer working life and produce 22% to 27% less CO2 emissions and lower annual degradation than those using a film, which the researchers believe further improves their carbon footprint. "Unfortunately, only a few manufacturers opt for frameless glass-glass modules," they add.
Fraunhofer ISE's analysis is based on data collected at the institute in collaboration with the industry.
"This is the real news. Compared to life cycle analyses based on older data sets that are still used today, the study showed that the carbon footprint of PV modules has improved by about 80 percent in recent years," explained Fraunhofer ISE's Head of Department for Module Technology Dr. Holger Neuhaus. "This is due to improvements in the silicon yield, the manufacturing processes of module efficiency and the CO2 intensity of power generation."
Fraunhofer ISE uses these arguments to stress on establishing PV production chain in Europe quickly and 'with a great deal of commitment'. Currently, China dominates the global PV supply chain. As per Fraunhofer ISE, in 2019 the Asian giant accounted for 68% polysilicon, 96% of all wafers, 76% of all solar cells and 71% of all modules.