CEM Renewable Energy Systems 2

Question 1

In a grid-tied solar PV system, what is the primary function of the inverter?

Accepted Answer

Convert DC power from solar panels into AC power compatible with the building and grid

Answer

Store excess solar energy in a battery bank for nighttime use

Answer

Convert AC power from the utility grid to DC for the solar panels

Answer

Regulate water circulation in solar thermal collectors

Question 2

What is the wind speed at which a wind turbine first begins generating electricity called?

Accepted Answer

Cut-in speed

Answer

Rated speed

Answer

Cut-out speed

Answer

Survival speed

Question 3

Which type of solar thermal collector is most appropriate and cost-effective for low-temperature applications such as swimming pool heating?

Accepted Answer

Unglazed flat-plate collector

Answer

Parabolic trough concentrating collector

Answer

Evacuated tube collector

Answer

Central receiver power tower

Question 4

What does the metric 'peak sun hours' represent for a solar installation site?

Accepted Answer

The equivalent daily hours at 1,000 W/m² irradiance that delivers the same energy as actual daily solar radiation

Answer

Total hours per day that the sun is above the horizon

Answer

Hours when solar panel surface temperature is highest

Answer

The hours between 10 AM and 2 PM when solar output exceeds 80% of rated capacity

Question 5

Which statement best describes a biomass energy system?

Accepted Answer

Combusting or thermochemically converting organic materials to produce heat or electricity

Answer

Converting kinetic energy of ocean waves into electricity via underwater turbines

Answer

Using temperature differentials between deep and surface ocean water to generate power

Answer

Producing hydrogen fuel from water using photocatalytic solar reactions

Question 6

What is the primary operational advantage of a run-of-river microhydro system compared to wind or solar installations?

Accepted Answer

Ability to generate consistent baseload power 24 hours a day from continuous water flow

Answer

Zero noise or vibration output during operation

Answer

Lower installed cost per kilowatt than any other renewable technology

Answer

No civil works or water intake structure required

Question 7

What is the primary purpose of a solar charge controller in a stand-alone off-grid PV system?

Accepted Answer

Regulate charging current to batteries and prevent overcharging or excessive discharge

Answer

Convert DC power from solar panels to AC power for loads

Answer

Track the maximum power point of the solar array under varying conditions

Answer

Monitor and report grid frequency and voltage to the utility