What temperature exists inside a solar collector (effective collection area of 15 m²) on a bright sunny day when the outside temperature is +20°C? Assume that the collector is thermally insulated, that the Sun radiates the collector with a power per unit area of 600 W/m², and that the collector acts as a perfect blackbody.

Question

Quizplus · Accepted Answer

The power absorbed by the collector is 600 W/m² * 15 m² = 9000 W. As a perfect blackbody, it emits power according to the Stefan-Boltzmann law: P = σAT⁴. Solving for T, we find T ≈ 366 K, which is approximately 93°C.

What Temperature Exists Inside a Solar Collector (Effective Collection Area