Solar power is one of the key pillars of the global energy transition, and the rapid expansion of solar photovoltaic (PV) manufacturing has helped drive down technology costs and accelerate deployment worldwide. At the same time, the unprecedented growth of manufacturing capacity has raised concerns about overcapacity across the solar PV supply chain. Public discussions of this issue, however, do not always clearly distinguish between manufacturing overcapacity, low utilization rates and actual overproduction. These concepts describe different market conditions and can require different policy and industry responses.

China, which accounts for the majority of global PV manufacturing capacity, is at the center of this debate. This expert note examines whether rapid manufacturing capacity expansion has translated into persistent surplus production of PV modules in China. Using module production, export and domestic installation data from 2015 to 2024, the analysis explicitly accounts for the time between module procurement and project installation and grid connection. It finds that incorporating a six-to-seven-month lead time substantially improves the alignment between domestically available module supply and implied domestic demand. This suggests that much of the apparent gap between production and deployment reflects timing differences rather than persistent accumulation of unsold modules.

These findings do not mean that manufacturing overcapacity is absent. The global solar PV manufacturing sector continues to face significant structural pressures, including low utilization rates, declining prices and weak profitability, while inventory pressures may also differ across stages of the supply chain. Rather, the analysis shows why overcapacity should not automatically be interpreted as overproduction.

Clearly identifying the nature and boundaries of these challenges is important for both policymakers and industry stakeholders. Distinguishing between excess manufacturing capacity, low utilization and persistent surplus production can help ensure that policies and business strategies are targeted at the underlying problem rather than treating different supply-chain pressures as the same issue.

Key Findings:

  • Manufacturing overcapacity does not necessarily mean overproduction. Global solar PV manufacturing capacity substantially exceeds near-term demand, but excess capacity and low utilization rates should be distinguished from actual overproduction, which would result in persistent accumulation of unsold products.
  • Much of the apparent gap between China’s PV module supply and domestic deployment can be explained by project lead times. The analysis finds an estimated six-to-seven-month lag between modules becoming domestically available and project grid connection. Accounting for this lag substantially improves the alignment between module supply and implied domestic demand.
  • The analysis finds no evidence of persistent accumulation of unsold PV modules in China’s domestic market. Under the six-to-seven-month lead-time assumptions, supply-demand residuals fluctuate around zero over 2015–23, suggesting that apparent annual imbalances largely reflect differences in the timing of manufacturing, procurement and project commissioning rather than systematic module overproduction.