CEA Lighting & HVAC Energy Analysis 2

Question 1

A facility manager wants to reduce lighting energy use by installing occupancy sensors in private offices. What percentage energy savings is typically achievable in private office spaces?

Accepted Answer

40–50%

Answer

Occupancy sensors in private offices typically reduce lighting energy by 40–50% because offices are frequently unoccupied during the workday.

Question 2

Which HVAC system type uses a single refrigerant circuit to serve multiple indoor units, allowing individual zone control?

Accepted Answer

Variable refrigerant flow (VRF) system

Answer

VRF systems use one refrigerant circuit connected to multiple indoor fan-coil units, enabling independent zone temperature control.

Question 3

What does a Lighting Power Density (LPD) value measure?

Accepted Answer

Watts of lighting power per square foot of floor area

Answer

LPD is expressed in watts per square foot (W/ft²) and is the primary metric used by ASHRAE 90.1 to regulate interior lighting energy use.

Question 4

In HVAC energy analysis, what is the significance of the 'bin method'?

Accepted Answer

It groups outdoor temperature hours into bins to estimate annual energy consumption

Answer

The bin method divides annual outdoor temperature data into temperature bins, then calculates energy use at each bin to estimate total annual HVAC energy consumption.

Question 5

A T8 fluorescent lamp operates at 32 watts. An equivalent LED tube replacement operates at 18 watts. What is the percentage wattage reduction?

Accepted Answer

44%

Answer

The reduction is (32−18) ÷ 32 = 14 ÷ 32 ≈ 43.75%, which rounds to approximately 44%.

(CEA) Certified Energy Analyst Practice Test

(CEA) Certified Energy Analyst Practice Test

CEA Lighting & HVAC Energy Analysis 2