A recent study comparing the carbon footprint and energy efficiency of solar photovoltaic (PV) technologies produced in China, the EU, and the USA has revealed significant insights into how much CO2 these technologies emit throughout their life cycles. The findings provide essential guidance for policymakers and the solar industry in determining which technologies and regions offer the most sustainable production methods.

The study assessed the energy return on energy invested (EROI) and net energy return on carbon invested (EROC) across different solar PV technologies, including mono-crystalline silicon (Mono-Si), multi-crystalline silicon (Multi-Si), and thin-film technologies like CdTe and CIS. The results show that while energy efficiency largely depends on the type of technology used, the carbon footprint is influenced not only by the technology but also by the region of production.

Energy Footprint: A Matter of Technology

When it comes to the energy footprint, the research shows that the amount of energy consumed in producing solar panels is determined primarily by the technology itself, not the country of origin. Mono-Si technology, which is widely used in the solar industry, requires significantly more energy due to its complex manufacturing process. In contrast, thin-film technologies, such as CdTe and CIS, are much more energy-efficient, requiring less energy during production.

Regardless of where the panels are made—whether in China, the EU, or the USA—the energy consumption is dictated by the type of technology. This means that companies looking to reduce the energy footprint of their solar products should focus on adopting more energy-efficient technologies like CdTe and CIS.

Carbon Footprint: Technology and Country of Origin Play Crucial Roles

However, when it comes to carbon emissions, both the technology and the region of production play vital roles. The study highlights that Mono-Si panels, while widely adopted, have the highest carbon footprint due to the energy-intensive nature of their production. On the other hand, CdTe panels are the most carbon-efficient, emitting the least CO2 over their life cycles.

The carbon intensity of the production process is highly influenced by the energy sources used in manufacturing. Solar panels produced in the EU have the lowest carbon emissions because of the region's heavy reliance on renewable energy and nuclear power during production. The USA comes next, while China, still heavily reliant on coal, produces solar panels with a much higher carbon footprint.

Figures 1 and 2: Key Insights

• Figure 1 from the study illustrates the energy consumption of different PV technologies across regions. It shows that while Mono-Si requires the most energy to produce, thin-film technologies like CdTe and CIS consume far less energy.
• Figure 2 demonstrates the stark differences in carbon dioxide emissions between these technologies and regions. Mono-Si emits the most CO2, while CdTe is the lowest-emitting technology. The EU stands out as the region with the lowest carbon footprint, followed by the USA and China.

Implications for Solar Energy Policy and Adoption

These findings underscore the importance of considering both technology and production location when selecting solar PV systems for large-scale deployment. While energy efficiency can be improved by adopting better technologies, the carbon emissions can be drastically reduced by sourcing panels from regions that rely on cleaner energy mixes.

The study also stresses the importance of policy interventions, such as carbon pricing, to drive innovation in lower-carbon production processes. Without systemic policies in place, the adoption of low-carbon PV technologies may be delayed, ultimately hindering the transition to a more sustainable energy future.

At BIPV.green, we believe that insights like these are critical to making informed decisions that align with the global push for a low-carbon economy. As the demand for solar energy grows, it's essential that we not only focus on the deployment of solar technologies but also on how and where these technologies are produced.

By supporting energy-efficient technologies like CdTe and CIS, and advocating for cleaner production processes, we can accelerate the shift to a more sustainable and environmentally friendly solar energy system.