Solar PV Fundamentals Flashcards

What is the term for the voltage a PV module produces under open-circuit conditions with no load connected?

Answer: Open-circuit voltage (Voc)

Open-circuit voltage (Voc) is the maximum voltage a module produces when no current is flowing through it.

Which semiconductor material is used in the majority of commercially installed crystalline silicon PV modules?

Answer: Monocrystalline or polycrystalline silicon

Monocrystalline and polycrystalline silicon dominate the commercial PV market due to high efficiency and established manufacturing.

How does increasing cell temperature affect the power output of a crystalline silicon PV module?

Answer: Power decreases primarily due to reduced Voc

Higher temperatures reduce Voc more than they increase Isc, resulting in a net decrease in module power output.

What is the standard test condition (STC) irradiance value used to rate PV module output?

Answer: 1000 W/m²

STC specifies 1000 W/m² irradiance, 25°C cell temperature, and an AM1.5 solar spectrum.

In a PV I-V curve, where does the module operate to deliver maximum power?

Answer: At the knee of the curve where the product V×I is maximized

The maximum power point (MPP) is located at the knee of the I-V curve where the product of voltage and current is greatest.

What does the term 'fill factor' (FF) indicate about a PV module?

Answer: How closely the module's power output approaches the product of Voc and Isc

Fill factor is Pmax divided by (Voc × Isc), indicating how 'square' the I-V curve is and the quality of the module.

Which condition causes bypass diodes in a PV module to conduct current?

Answer: When one or more cells are shaded or underperforming

Bypass diodes activate when shaded cells would otherwise become reverse-biased and dissipate power as heat, creating a hot spot.