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.
Which billing demand charge is typically based on the highest 15-minute average power demand recorded during the billing period?