REP Solar Energy Systems 2

Question 1

What is the primary function of a bypass diode in a photovoltaic module?

Accepted Answer

Prevent reverse current flow through shaded cells

Answer

Bypass diodes allow current to flow around shaded or damaged cells, preventing hotspot damage and maintaining power output.

Question 2

Which solar resource metric best represents the equivalent number of peak sun hours at a site?

Accepted Answer

Plane of Array (POA) irradiance

Answer

Plane of Array irradiance accounts for panel tilt and orientation and is the most directly relevant metric for estimating energy yield from a fixed PV system.

Question 3

A string of 12 PV modules each rated at 40V open-circuit voltage is connected in series. What is the maximum string open-circuit voltage?

Accepted Answer

480 V

Answer

Series-connected modules sum their voltages, so 12 × 40 V = 480 V open-circuit voltage.

Question 4

What does a solar inverter's 'anti-islanding' protection do?

Accepted Answer

Shuts down the inverter when grid power is lost

Answer

Anti-islanding protection automatically disconnects the inverter from the grid during an outage to protect utility workers from unexpected energized lines.

Question 5

In a grid-tied PV system, what component is responsible for maximum power point tracking (MPPT)?

Accepted Answer

Inverter or charge controller

Answer

The inverter (in grid-tied systems) or charge controller (in off-grid systems) performs MPPT to continuously extract maximum power from the array.

(REP) Certified Renewable Energy Professional Practice Test

(REP) Certified Renewable Energy Professional Practice Test

REP Solar Energy Systems 2