How does irradiance affect energy yield per unit area?

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When irradiance goes up, more photons reach the solar cell, so the instantaneous electrical output rises and energy per unit area tends to increase. But the story isn’t just about more light. As irradiance increases, the module temperature typically rises, which lowers the open-circuit voltage and overall efficiency, so the gain in energy yield isn’t perfectly proportional. The spectrum of the light also matters—different wavelengths are converted with different efficiency, and changes in the spectrum with time or atmospheric conditions can shift how much energy is produced. Plus, real-world system losses—wiring, connections, inverter efficiency, shading, and other losses—eat into the output and can vary with irradiance. So the energy yield per unit area increases roughly with irradiance, but temperature, spectral effects, and system losses all influence the final yield.