Since the 1970s, the cost of solar panels has tumbled by more than 99%, and an MIT-led study explores how this monumental decline occurred. Their findings shed light on a diverse array of innovations—many originating outside the solar sector—that collectively drove cost reductions in both photovoltaic (PV) modules and balance-of-system (BOS) components, says this article on MIT News.
The team, led by Prof. Jessika Trancik of MIT’s Institute for Data, Systems, and Society, developed a hybrid method combining quantitative modeling and qualitative literature analysis. This allowed them to trace technological changes affecting the cost of materials, manufacturing steps, and deployment practices. Ultimately, the researchers pinpointed 81 individual innovations since 1970 across multiple domains that eased cost pressures.
PV module cost savings were especially impacted by innovations originating in industries such as semiconductor fabrication, metallurgy, glass manufacturing, and oil & gas drilling. These advancements, ranging from refined wafer processing to glass coating technologies, were repurposed to benefit solar panel production. On the BOS side—covering elements such as mounting systems, wiring, and approvals—innovations spanned software engineering (e.g., permitting fast-tracking tools), utility processes, and construction methods.
Trancik emphasizes the key insight: this cost evolution wasn’t driven by solar-focused research alone, but by a broader network of knowledge spillovers.
Interestingly, while most PV innovations came from research institutions and industries, many BOS breakthroughs arose from municipal governments, regulatory bodies, or professional associations—especially innovations targeting procedural inefficiencies like permitting delays.
The modeling framework also offers predictive potential: given numerical cost data, stakeholders could simulate the impact of future technologies or reforms. This capability could guide R&D investment decisions and policy actions not just for solar, but for other renewable systems, battery infrastructure, and decarbonisation technologies.
In short, the study uncovers that solar’s astonishing cost drop stems from decades of interconnected, multi-domain innovation—from core materials science to policy-level procedural improvements. Understanding this rich tapestry of contributions offers practical direction for sustaining momentum in clean energy affordability.