CEM Certified Energy Manager Audit & Billing 2 — Questions and Answers
Question 1: Which billing demand charge is typically based on the highest 15-minute average power demand recorded during the billing period?
- Ratchet demand
- Peak demand charge (Correct answer)
- Coincident demand
- Non-coincident demand
Correct answer: Peak demand charge
Peak demand charges are assessed based on the highest 15-minute average kW demand recorded within the billing period.
Question 2: A ratchet clause in a utility tariff typically bills the customer based on what percentage of their peak demand recorded over a specified prior period?
- 50%
- 75% (Correct answer)
- 85%
- 100%
Correct answer: 75%
Most ratchet clauses bill the higher of actual demand or 75% of the peak demand recorded within the past 11–12 months.
Question 3: During an energy audit, the auditor identifies that a facility's power factor averages 0.78. What is the MOST likely financial consequence?
- Reduced energy consumption charges
- Power factor penalty on the utility bill (Correct answer)
- Lower peak demand readings
- Reduced reactive power generation
Correct answer: Power factor penalty on the utility bill
Utilities impose power factor penalties when power factor falls below a threshold (commonly 0.85 or 0.90), increasing the effective billing demand.
Question 4: When reviewing a natural gas bill, a CEM notices a 'therm' unit. One therm is equivalent to approximately how many BTUs?
- 10,000 BTU
- 100,000 BTU (Correct answer)
- 1,000,000 BTU
- 10,000,000 BTU
Correct answer: 100,000 BTU
One therm equals 100,000 BTU, a common natural gas billing unit in the United States.
Question 5: An energy auditor discovers interval data showing high demand spikes only between 7:00–9:00 AM on weekdays. The BEST initial recommendation is to:
- Install capacitor banks
- Implement load shifting to off-peak hours (Correct answer)
- Upgrade transformer capacity
- Switch to time-of-use rate schedule
Correct answer: Implement load shifting to off-peak hours
Load shifting moves energy-intensive processes from peak to off-peak periods, directly reducing demand charges.
Question 6: Which type of energy audit provides the most detailed analysis including capital cost estimates and ROI calculations for specific measures?
- Level I (Walk-Through Audit)
- Level II (Energy Survey and Analysis)
- Level III (Detailed Analysis of Capital Intensive Modifications) (Correct answer)
- Preliminary Energy Use Analysis
Correct answer: Level III (Detailed Analysis of Capital Intensive Modifications)
A Level III audit provides detailed engineering analysis, accurate cost estimates, and financial metrics for capital-intensive projects.
Question 7: On a utility electric bill, the 'energy charge' component bills for:
- Peak kW demand during the month
- Total kilowatt-hours consumed (Correct answer)
- Reactive power in kVAR
- Transmission and distribution losses only
Correct answer: Total kilowatt-hours consumed
The energy charge is calculated by multiplying the total kWh consumed during the billing period by the applicable rate per kWh.
