Certified Energy Auditor Certification Data Collection and Analysis 2 — Questions and Answers
Question 1: Which instrument is used to measure the airtightness of a building envelope?
- Blower door (Correct answer)
- Combustion analyzer
- Pyranometer
- Infrared thermometer
Correct answer: Blower door
A blower door depressurizes the building to measure air leakage through the envelope.
Question 2: What does a lighting power density (LPD) calculation require?
- Total wattage of fixtures divided by floor area (Correct answer)
- Lamp lumens multiplied by ballast factor
- Number of fixtures multiplied by hours of operation
- Voltage times current divided by power factor
Correct answer: Total wattage of fixtures divided by floor area
LPD is expressed in watts per square foot and equals total connected wattage divided by the conditioned floor area served.
Question 3: When benchmarking a facility's energy use, which metric normalizes consumption across buildings of different sizes?
- Energy Use Intensity (EUI) (Correct answer)
- Peak demand (kW)
- Annual energy cost ($)
- Load factor (%)
Correct answer: Energy Use Intensity (EUI)
EUI divides annual energy consumption by gross floor area, enabling fair cross-building comparisons.
Question 4: A chiller log shows entering condenser water temperature consistently 5°F above design. What analytical step should an auditor take first?
- Compare actual vs. design cooling tower performance curves (Correct answer)
- Replace the chiller refrigerant charge
- Reduce chilled water set point
- Increase condenser pump speed
Correct answer: Compare actual vs. design cooling tower performance curves
Elevated condenser water temperature usually indicates cooling tower degradation, so comparing actual vs. design tower performance is the correct diagnostic step.
Question 5: Which data source provides historical utility billing intervals that help identify demand spikes?
- Interval data from the utility meter (Correct answer)
- ASHRAE 90.1 tables
- Equipment nameplate data
- ENERGY STAR Portfolio Manager baseline
Correct answer: Interval data from the utility meter
Utility interval (15-minute or hourly) meter data captures the demand profile needed to identify peak demand events.
Question 6: What is the primary purpose of a degree-day analysis in energy auditing?
- Normalize energy consumption for weather variation across years (Correct answer)
- Calculate peak thermal loads for HVAC sizing
- Determine equipment runtime in summer months only
- Estimate lighting energy use independent of occupancy
Correct answer: Normalize energy consumption for weather variation across years
Degree-day normalization adjusts utility data for heating and cooling weather differences, enabling year-over-year comparisons.
Question 7: During a walk-through audit, an auditor notices motor nameplate data shows 460V/3-phase but the panel schedule lists 480V. What should be recorded?
- The voltage discrepancy as a potential efficiency and reliability concern (Correct answer)
- Only the panel schedule voltage as authoritative
- A recommendation to replace all motors immediately
- Nothing, because 460V and 480V motors are interchangeable without concern
Correct answer: The voltage discrepancy as a potential efficiency and reliability concern
Voltage mismatches can affect motor performance and longevity, so both values should be documented and flagged for investigation.
Certified Energy Auditor Certification Data Collection and Analysis 2
Which instrument is used to measure the airtightness of a building envelope?