Manufacturing next-generation solar panels could cut global carbon emissions by up to 8.2 billion tonnes by 2035, finds a new international study by researchers from the University of Warwick and Northumbria, Birmingham, and Oxford Universities.
Solar panels, known scientifically as photovoltaics (PV), convert sunlight directly into electricity and are central to global decarbonisation. But as countries race to deploy solar at multi-terawatt scale, the carbon footprint of manufacturing these devices is coming under increasing scrutiny.
At the same time, the industry is rapidly shifting from the current industry-standard design, passivated emitter rear cell (PERC), to a newer and more efficient architecture known as tunnel oxide passivated contact (TOPCon) photovoltaics. Until now, however, the full environmental implications of this transition have not been comprehensively assessed.
In new research, published in Nature Communications, the team compares the complete manufacturing lifecycle of both photovoltaic technologies to determine whether the newer TOPCon technology can reduce the environmental footprint of solar production as global deployment accelerates.
“Multi terawatt scale photovoltaic manufacturing demands a sharper focus on its full environmental footprint”, says Dr Nicholas Grant, Associate Professor, at University of Warwick. “Our paper shows how targeted improvements across the supply chain can deliver sustainable manufacturing at the terawatt-scale, avoiding twenty-five gigatonnes of manufacturing related CO₂ emissions if installed by 2035, while supporting rapid global deployment.”
Using life-cycle assessment modelling, the team found that producing the newer TOPCon panels has lower environmental impacts in fifteen out of sixteen categories as compared to the incumbent PERC technology. This includes a 6.5% reduction in climate-changing emissions per unit of electricity capacity, with increased silver consumption being the only downside as it depletes critical minerals.
The study also highlights the importance of manufacturing location for the future solar manufacturing. Producing photovoltaics using low-carbon electricity – such as in Europe – significantly reduces emissions compared with fossil-fuel-dependent grids. Combining TOPCon adoption, manufacturing improvements, and grid decarbonisation was found to potentially reduce solar manufacturing emissions by up to 8.2 gigatonnes of CO₂ equivalent by 2035 — around 14% of current global annual emissions. In addition, photovoltaics installed between 2023 and 2035 are projected to avoid more than 25 gigatonnes of carbon emissions by replacing fossil fuel electricity.
“Solar photovoltaics is a critical technology that can be used globally now to significantly reduce greenhouse gas emissions and create energy security,” said senior author Professor Neil Beattie, Northumbria University. “This is especially important as our demand for electricity soars over the next decade driven by applications in transport, heating, and digital infrastructure for AI. Even when manufacturing impacts are considered, solar photovoltaics remains one of the lowest-impact and most sustainable electricity generation technologies available over its whole life cycle and we should concentrate on deploying it at scale, now.”
