Certified Energy Auditor Certification Energy Audit Data Analysis 2 — Questions and Answers
Question 1: When analyzing utility bills for an energy audit, what does a high load factor indicate?
- Demand charges are disproportionately high relative to consumption
- Electricity consumption is relatively consistent throughout the billing period (Correct answer)
- The facility has significant seasonal energy variation
- Peak demand occurs primarily during off-peak rate hours
Correct answer: Electricity consumption is relatively consistent throughout the billing period
A high load factor (kWh / (peak kW × hours)) means demand is steady relative to peak, indicating consistent utilization throughout the billing period.
Question 2: A facility's energy use intensity (EUI) is 120 kBtu/ft²/yr. The national median for its building type is 80 kBtu/ft²/yr. What does this indicate?
- The facility is more energy efficient than average
- The facility uses 50% more energy per square foot than the median (Correct answer)
- The facility's energy costs are 50% above national average
- The facility qualifies for ENERGY STAR certification
Correct answer: The facility uses 50% more energy per square foot than the median
An EUI of 120 vs. a median of 80 means the facility consumes 50% more energy per square foot than the typical building of its type.
Question 3: What is the primary purpose of degree-day normalization in energy data analysis?
- To convert energy units between kWh and therms
- To remove the effect of weather variation when comparing energy use across periods (Correct answer)
- To calculate the efficiency of HVAC equipment
- To determine peak demand coincidence with utility pricing periods
Correct answer: To remove the effect of weather variation when comparing energy use across periods
Degree-day normalization adjusts energy consumption data to account for weather differences, enabling fair year-to-year or site-to-site comparisons.
Question 4: During regression analysis of a building's energy use, the R² value is 0.95. What does this mean?
- The model has a 5% error rate in predicting future energy use
- 95% of the variation in energy use is explained by the independent variable(s) in the model (Correct answer)
- The building's energy efficiency is rated at 95%
- The regression line slope is 0.95 kWh per degree-day
Correct answer: 95% of the variation in energy use is explained by the independent variable(s) in the model
An R² of 0.95 means the regression model's independent variables (e.g., degree-days) explain 95% of the variance in the energy consumption data.
Question 5: An energy auditor finds that a building's electricity consumption drops significantly on weekends. This pattern most likely indicates:
- A malfunctioning utility meter
- Process or occupancy-related loads that cease during non-business hours (Correct answer)
- Demand response participation by the facility
- Incorrect billing by the utility
Correct answer: Process or occupancy-related loads that cease during non-business hours
Significant weekend consumption drops typically reflect occupancy-driven loads such as lighting, plug loads, and HVAC setback during unoccupied periods.
Question 6: What does the term 'baseload' refer to in energy consumption analysis?
- The maximum demand recorded during a billing period
- The minimum level of energy consumption that occurs regardless of weather or occupancy (Correct answer)
- The energy used exclusively by HVAC systems
- The utility's base charge before consumption tiers apply
Correct answer: The minimum level of energy consumption that occurs regardless of weather or occupancy
Baseload is the constant minimum energy consumption present regardless of weather variations, representing always-on loads like servers, refrigeration, and standby equipment.
Question 7: A measured and verified (M&V) analysis shows actual post-retrofit savings are 15% below projected savings. What is the most likely explanation?
- The energy model used an incorrect baseline period
- Interactive effects between measures were not accounted for in the original projection (Correct answer)
- The utility changed its rate structure after the retrofit
- Measurement equipment was not calibrated correctly
Correct answer: Interactive effects between measures were not accounted for in the original projection
Interactive effects—where one measure reduces the savings potential of another (e.g., efficient lighting reducing HVAC cooling load)—are a common cause of actual savings falling short of simple additive projections.
