Which factor besides irradiance can influence PV energy yield per unit area?

Master the Gate 6 Airstreams Renewables Test with a variety of questions, in-depth explanations, and unique insights. Prepare and excel with confidence!

PV energy per unit area depends on more than just the amount of sunlight reaching the panel; temperature plays a crucial role too. As the module temperature rises, the electrical characteristics of the silicon cells change in a way that reduces the maximum power they can produce. The key idea is captured by the temperature coefficient: for many panels, electrical power declines by a few percent for each degree Celsius rise above the standard testing conditions. So even with the same irradiance, hotter panels will yield less energy per square meter because their efficiency drops.

In more detail, increasing temperature mainly lowers the open-circuit voltage and, to a lesser extent, changes the short-circuit current. The net effect is a decrease in maximum power output (Pmax) per unit area. This is why installers consider both irradiance and operating temperature when estimating real-world energy yield.

The other options don’t fit as well: panel color doesn’t meaningfully change the electrical output per area, and while wiring length can cause losses in the system, it doesn’t alter the PV cell’s output per unit area under standard conditions. The statement that only irradiance matters ignores the real-world impact of temperature on PV performance.