With global photovoltaic (PV) capacity exceeding 1,200 GW and projected to double within a decade, the solar sector faces a mounting end-of-life (EoL) dilemma: by 2050, PV waste could exceed 78 million metric tons globally. Current waste management infrastructure is unprepared for this surge, primarily because solar energy deployment has vastly outpaced corresponding circular economy planning.
The rapid accumulation of PV waste, particularly from crystalline silicon panels—the industry’s dominant technology—poses both a material recovery challenge and a missed economic opportunity. Silicon, silver, aluminum, and rare earths embedded in PV panels represent significant resource value. Yet, under prevailing linear waste systems, most of this value is either landfilled or underutilized due to inefficient recycling protocols and low recovery rates.
Iseri et al. propose a shift from this conventional model through a Circular Economy Systems Engineering (CESE) framework, a structured, feedback-driven process that integrates technical, economic, and environmental decision-making across the panel lifecycle. By adopting CESE, the PV industry could avoid the common pitfalls of traditional EoL strategies, such as single-loop recycling or delayed policy implementation.
The proposed CESE framework consists of four nested layers—Product Lifecycle, Circular Business, Industrial Symbiosis, and Governance—each informed by systems engineering principles. For instance, the Product Lifecycle layer emphasizes Design for Disassembly and modularization to enhance repairability and component reuse. This is critical given that most PV panels were not originally designed with decommissioning or recyclability in mind.
Industrial symbiosis also features prominently. Rather than treating PV waste in isolation, the authors argue for a synergistic approach where waste streams are valorized by adjacent sectors, such as the construction or electronics industries. This intersectoral reuse not only enhances material efficiency but could offset processing costs that currently make PV recycling economically marginal.
However, the paper is not blind to existing market limitations. The lack of standardized protocols, the absence of robust economic incentives, and fragmented regulatory environments all hinder progress. In particular, Extended Producer Responsibility (EPR)—a policy mechanism successful in other electronics sectors—has not been uniformly adopted for PV panels. This leaves responsibility for panel recovery diffuse and underfunded.
Economic feasibility remains a sticking point. Current PV recycling processes often operate at a loss, with material recovery rates of high-value elements like silver or silicon falling below economically viable thresholds. The CESE framework addresses this by embedding cost-benefit analyses at each stage, helping stakeholders identify the most impactful interventions—whether through upstream design changes or downstream processing innovation.
The paper also underscores the urgency of proactive policy development. The average PV panel lasts 25–30 years, and the early-2000s installation boom is now nearing its decommissioning phase. Waiting until volumes become unmanageable risks locking in inefficient systems. Instead, the authors advocate for anticipatory regulation tied to the CESE framework, enabling governments to shape circularity through targeted procurement, incentives, and performance standards.
A key strength of the CESE framework lies in its adaptability. It is not prescriptive but modular—allowing for region-specific applications and scaling with technological change. This is essential in a global market characterized by diverse regulatory environments, manufacturing ecosystems, and energy transition pathways.
In the broader context of energy system decarbonization, PV waste management has been largely sidelined in favor of generation capacity growth. Yet, as the CESE framework reveals, integrating circularity from the outset is not a luxury but a prerequisite for long-term system sustainability. The paper positions this integration not as a retrofit but as a necessary evolution of how renewable energy infrastructure is designed, deployed, and eventually retired.
