Is Solar Power Generation Truly “Zero Pollution”?

As the world races toward carbon neutrality, solar energy is often billed as the ultimate clean power. Yet a joint study released today by the Chinese Academy of Environmental Sciences and the National Renewable Energy Center warns that photovoltaics are not “absolutely zero-pollution” when their full life-cycle is counted.
The report finds that producing one kilogram of polysilicon via the dominant Siemens route consumes roughly 65 kWh of electricity; if that power comes from coal, up to 35 kg of CO₂-equivalent is emitted—about one-quarter of the carbon footprint of a standard 180 W module. Ingot casting and wafering rely on polyethylene-glycol cutting fluid; without closed-loop treatment, chemical-oxygen demand (COD) in wastewater can exceed legal limits by a factor of three.
The bigger shock is the coming waste wave. China will have 1.2 million tonnes of end-of-life panels by 2030. While aluminum frames and glass are easy to recycle, fluorinated back-sheets and EVA encapsulants can release perfluorinated compounds (PFCs) when incinerated—persistent organic pollutants that linger for centuries.
In response, the Ministry of Industry and Information Technology (MIIT) has launched a “PV Recycling Leader” program, mandating ≥75 % collection rates and ≥60 % material recovery by 2025. Leading firms such as Amosolar already operate 100 % renewable-powered factories, use lead-free solder and water-soluble back-sheets, and have cut production-phase carbon emissions by 68 %.
Experts conclude that “zero pollution” should be reframed as “controllable, reducible and circular.” With cleaner grids and mandatory recycling, solar remains the single biggest lever for global decarbonization—provided the industry cleans up its own supply chain first.