A novel framework for energy yield simulation has been developed to analyze the performance of Copper Indium Gallium Selenide (CIGS) solar cells, particularly their limitations compared to traditional crystalline silicon (c-Si) photovoltaic (PV) technologies. This framework is significant for enhancing the viability of CIGS, especially as the global push for sustainable energy solutions intensifies.
The study reveals noteworthy insights about CIGS technology, which, after significant enhancements, has achieved efficiencies exceeding 23% on lab scales but still faces challenges for broader commercialization. The research, conducted by imec/EnergyVille researchers, provides a comprehensive evaluation of CIGS, focusing on its energy yield under diverse environmental conditions.
This energy yield framework utilizes advanced modeling techniques to accurately simulate the performance of CIGS modules, especially under various temperature regimes and irradiance levels. One of the key findings indicates CIGS modules exhibit slightly lower efficiency during low-light conditions due to notable voltage losses, which are particularly problematic for their adoption.
Through benchmarking against c-Si PERC technology, the newly developed model showed exceptional accuracy with error metrics indicating normalized mean bias error (nMBE) values around 1% and normalized root mean square error (nRMSE) of 8% to 20%, depending on the setup. The results indicate CIGS technology, though it tends to lag under low light, can outperform its c-Si counterparts under high irradiation and elevated temperatures.
Researchers emphasized the need for enhancing the diode ideality factor within CIGS cells to improve their performance during low-irradiance scenarios. This aspect has become increasingly significant as demand for versatile and efficient solar technologies grows. Advances such as the integration of CIGS within tandem configurations are paving the way for improved performance metrics; tandem cells combining CIGS with perovskite materials have already displayed efficiencies exceeding 25%.
The findings of the study are pivotal as global interest and investment shift toward CIGS, spurred by the need for sustainable energy solutions sustainably sourced through geo-political stability. The International Energy Agency and others stress the importance of resilient supply chains, positioning CIGS as strategically significant due to its dependence on more widely available resources.
The research methodology included rigorous outdoor monitoring setups across Belgium—which included both rack-mounted and integrated PV systems—and experimental assessments capturing data across varied climates, including periods of severe low-light conditions. The experimental results affirm the model's capability, demonstrating it must adapt to factors such as environmental shading and reflective elements integral to urban landscapes.
While the model itself shows promise for broader applications within both small-scale and large-scale projects, future research must focus on refining these techniques to lessen the impact of voltage losses at low irradiance levels. Improvements like optimizing the diode ideality factor signal potential breakthroughs for the commercial viability of CIGS technology.
Overall, the energy yield model's validation reflects its value within the PV technology development framework—promising advancements await, driven by targeted enhancements and consistent performance analysis.