Certified Energy Auditor Certification Renewable Energy Systems 2

Question 1

What does 'peak sun hours' mean as used in PV system sizing?

Accepted Answer

The equivalent number of hours per day with solar irradiance at exactly 1000 W/m²

Answer

The hours of the day when solar panels produce their highest instantaneous output

Answer

The total daily sunlight hours from sunrise to sunset at a specific location

Answer

The hours of daylight minus cloud cover hours at a given location

Question 2

For a fixed-tilt PV installation in the continental US, what is the general rule for maximizing annual energy production?

Accepted Answer

Set tilt angle equal to local latitude, oriented toward true south

Answer

Set tilt angle to 45° regardless of location, oriented toward magnetic south

Answer

Install panels horizontally (0° tilt) to maximize diffuse radiation capture

Answer

Set tilt angle equal to latitude minus 15°, oriented toward the east

Question 3

What is the typical annual degradation rate of crystalline silicon PV modules?

Accepted Answer

0.5% per year

Answer

2.0% per year

Answer

5.0% per year

Answer

10.0% per year

Question 4

Which inverter technology is best suited for maximizing energy harvest when individual PV panels may experience partial shading?

Accepted Answer

Microinverter or DC power optimizer

Answer

Central string inverter

Answer

Large central inverter

Answer

Line-interactive UPS inverter

Question 5

A rooftop PV system is rated at 50 kW STC. Using a derate factor of 0.80 and 5 peak sun hours per day, what is the estimated daily energy production?

Accepted Answer

200 kWh/day

Answer

250 kWh/day

Answer

150 kWh/day

Answer

400 kWh/day

Question 6

What is the primary function of a Maximum Power Point Tracker (MPPT) in a PV system?

Accepted Answer

To continuously adjust operating voltage to extract maximum power from PV panels

Answer

To prevent the PV system from exceeding the utility interconnection power limit

Answer

To monitor and report peak power output for manufacturer warranty compliance

Answer

To regulate battery charging voltage in off-grid systems only

Question 7

In evaluating a solar thermal system for domestic hot water, what does the 'solar fraction' indicate?

Accepted Answer

The proportion of total hot water energy demand supplied by the solar thermal system

Answer

The percentage of roof area covered by solar collectors

Answer

The ratio of useful heat collected to total solar radiation incident on the collector

Answer

The fraction of sunlight hours when the system operates above its minimum threshold temperature