GCL System Integration Technology Co. Solar Panel Series GCL-NT12/66GDF 700-720W. Detailed profile including pictures, certification details and manufacturer PDFCompare every GCL solar panel side by side: power, efficiency, temperature coefficient, dimensions and warranty. Full GCL panel catalog with independent specs. GCL is a global company focusing on green energy and high-efficiency photovoltaic materials. 95%), advanced N-type mono-crystalline cells, and bifacial technology for up to 30% rear-side power gain. Its low-temperature coefficient and PID resistance ensure reliable, high-performance energy.