CEM Renewable Energy and Cogeneration 2

Question 1

A fuel cell generates electricity through:

Accepted Answer

Electrochemical reaction of fuel and oxidant without combustion, producing electricity and heat

Answer

Fuel cells convert chemical energy directly to electricity via electrochemical reactions (no combustion), achieving higher efficiencies (40-60%) and producing heat as a recoverable byproduct.

Question 2

The overall efficiency of a CHP system is calculated as:

Accepted Answer

(Electrical output + recovered heat output) divided by total fuel input

Answer

CHP overall efficiency counts both useful electrical and thermal outputs, expressing total useful energy recovered as a fraction of fuel consumed.

Question 3

Levelized Cost of Energy (LCOE) for a renewable project is useful because it:

Accepted Answer

Expresses the average cost per kWh over the project lifetime, enabling comparison with utility rates

Answer

LCOE normalizes all project costs (capital, O&M, financing) over lifetime energy production, providing a comparable cost-per-kWh metric for evaluating against utility rates or alternative generation.

Question 4

The Investment Tax Credit (ITC) for solar energy systems in the US allows eligible projects to:

Accepted Answer

Claim a percentage of the installation cost as a direct federal income tax credit

Answer

The ITC allows commercial and residential solar owners to claim a percentage of the total system cost (currently 30% under the Inflation Reduction Act) as a direct federal tax credit.

Question 5

In a PV system, the maximum power point tracker (MPPT) in the inverter serves to:

Accepted Answer

Continuously adjust operating voltage to extract maximum power from panels under varying conditions

Answer

MPPT algorithms dynamically adjust the DC operating point of the PV array to continuously operate at the voltage/current combination yielding maximum power as irradiance and temperature change.

CEM - Certified Energy Manager Practice Test

CEM - Certified Energy Manager Practice Test

CEM Renewable Energy and Cogeneration 2