Engineers are designing a glass cover for a photovoltaic (PV) panel intended for use…
PHYSICS · Multi-part · CBSE · Physics · The Human Eye and the Colourful World · The Human Eye and the Colourful World
Problem
Engineers are designing a glass cover for a photovoltaic (PV) panel intended for use both in strong sunlight and under cloudy, diffuse daylight. To reduce glare seen by nearby pedestrians, the cover glass is micro-etched so that its surface height varies randomly with an rms value hrms. The PV panel must absorb as much of the solar spectrum (wavelengths 300nm to 2500nm) as possible while minimizing visual glare in the specular direction.
(a) Using qualitative reasoning, discuss how the choice of hrms relative to the visible wavelength band affects (i) the perceived glare and (ii) the fraction of incident visible light reaching the underlying photovoltaic cells.
(b) Suppose initial prototypes use hrms=1500nm. Evaluate whether this value simultaneously meets the goals stated above for both visible and near-infrared portions of the spectrum, providing specific supporting arguments.
(c) Propose one modification to the surface micro-etching strategy (such as altering the statistical distribution of heights or introducing a multi-scale texture) that could improve PV performance without significantly increasing glare. Justify how your proposal addresses both optical requirements.
(d) Explain one potential trade-off or practical limitation that engineers must consider when implementing your proposed modification in part (c).