Event Programme 2025

The tutorial will begin by surveying the properties and availability of sunlight, introducing the necessary measures and some commonly used data sources. A simple thermodynamic model for solar power conversion will be established to place an upper bound to the conversion efficiency of a photovoltaic cell.

The limits imposed by real materials will then be considered. First, the processes involved in absorption of photons in materials are introduced. Then it, will then be shown that extracting current from a semiconductor absorber leads to the usual measures for solar cell performance, short-circuit current, open-circuit voltage and fill factor and introduces additional constraints to photovoltaic power conversion leading to the Shockley-Queisser efficiency limit.

The carrier transport and recombination processes that are present in practical solar cells will be discussed. Key solar cell quality parameters will be introduced to give a conceptual understanding of material and device requirements for a high-efficiency solar cell. Characterisation methods such as dark current, quantum efficiency and, photoluminescence, and electroluminescence are discussed as means for understanding carrier lifetime and diffusion length, optical and resistive losses.

Having established a conceptual framework for PV devices the present laboratory status, manufacturing processes for several solar cell technologies will be reviewed, including:

• crystalline silicon
• III-V (2-terminal multi-junction)
• CdTe
• Perovskite, single junction and multi-junction with silicon

The tutorial will conclude with a brief perspective on the feasibility of deploying new materials in future power grids, including a consideration of the importance of PV material stability.

Critical aspects of PV module degradation and reliability form the core of the session: degradation mechanisms, technology trends, durability testing, modeling approaches, detection techniques, and economic analysis. The material bridges theoretical concepts with practical applications, providing foundational knowledge applicable to various industry contexts. Fundamental degradation mechanisms in current PV technologies begin with cell-level phenomena. Light-induced degradation, light and elevated temperature-induced degradation, and potential-induced degradation are examined with attention to underlying physical processes. Materials degradation including encapsulant discoloration, backsheet cracking, and corrosion mechanisms are discussed in relation to environmental stressors. Interconnection failures such as solder bond fatigue and contact degradation are explored through materials science principles.

Emerging PV technologies carry significant reliability implications. Advances in cell architectures including PERC, TOPCon, heterojunction, and thin-film technologies introduce new reliability considerations. Module design innovations analyzed through materials science principles highlight important gaps in current understanding. New encapsulants, thinner cells, thinner glasses, larger modules, and metallization approaches connect materials engineering with long-term performance considerations.

Accelerated testing methodologies are essential for PV reliability assessment. Standardized test protocols such as IEC 61215 and beyond-certification approaches are examined for their scientific foundations. Various stress factors including thermal cycling, damp heat, UV exposure, and mechanical load tests are explored through their physical mechanisms. Combined-stress and sequential testing approaches offer more realistic alternatives to single-stress methods. Correlating accelerated test results with real-world degradation requires sophisticated mathematical models for lifetime prediction.

Complementary approaches to degradation prediction include both physics-based and statistical methods. Stress-response frameworks link environmental stressors to specific degradation mechanisms. Statistical approaches applied at module and system levels provide alternative insights. Integration of physics principles with statistical methods offers opportunities for improved prediction accuracy.

Analytical and experimental methods for degradation assessment include field inspection techniques such as IR thermography, visual assessment, and I-V curve analysis, with emphasis on measurement principles. Advanced characterization methods include electro and photoluminescence imaging, UV fluorescence, and spectroscopic techniques, each with specific equipment capabilities and data interpretation approaches. Connecting visual evidence to specific degradation mechanisms requires systematic protocols.

Techno-economic approaches translate physical degradation into energy yield impact through mathematical models. Decision frameworks for intervention optimization connect reliability engineering with operations research. Statistical methods for analyzing large-scale PV fleets demonstrate the interdisciplinary nature of modern PV reliability. Fundamental science connects with economic impacts through practical examples that demonstrate how technical insights can address real-world challenges.

This tutorial will explore the dual role of photovoltaics (PV) in addressing climate change: first, as a major solution for decarbonising the energy system, and second, as a major industry whose own sustainability needs careful consideration.

We will begin by discussing the relevance and potential of PV to mitigate climate change. We will outline the role of PV in common decarbonisation pathways and examine why PV has the largest sustainable potential of all renewable technologies and has already become the cheapest source of electricity in most world regions. We will also reflect on the historical underestimation of PV—exploring how technological learning, economies of scale, and policy interventions have outpaced expectations, and what lessons this holds for current and future energy technologies. We will also discuss the role of associated technologies such as electricity networks, energy storage, demand management and complementary power sources in enabling PV to maximise its decarbonisation potential.

Next, the tutorial will take a hands-on, analytical approach to help participants understand how the deployment of clean technologies like PV translates into actual emissions reductions. While PV deployment has grown rapidly, the cumulative CO₂ displacement remains modest compared to global emissions. We will guide participants through the steps required to quantify the climate impact of PV and compare different PV growth scenarios.

In a second part, we will shift focus to the sustainability of the PV industry itself, acknowledging that even clean electricity has an ecological footprint. PV is not “free,” even if cheap, and its expansion must be done responsibly. We will consider how the CO₂ footprint of PV modules and balance-of-system components can be reduced—through efficiency gains, material choices, recycling, and supply chain decarbonisation.

This tutorial aims to equip participants with a solid understanding of the role and challenges of photovoltaics for climate change mitigation helping researchers, engineers, and policymakers to direct their activities to really make a difference for the climate.