CEM Methods and Strategies 3 — Questions and Answers
Question 1: Which measurement and verification (M&V) option under IPMVP is MOST appropriate when it is difficult to isolate individual measure savings?
- Option A — Partially Measured Retrofit Isolation
- Option B — Retrofit Isolation with Full Measurement
- Option C — Whole Facility (Correct answer)
- Option D — Calibrated Simulation
Correct answer: Option C — Whole Facility
Option C uses whole-facility metering to track energy changes, making it suitable when multiple measures interact or when individual isolation is impractical.
Question 2: What is the purpose of establishing an 'energy baseline' before implementing conservation measures?
- To set a maximum allowable energy budget
- To provide a reference for quantifying savings after implementation (Correct answer)
- To satisfy local building code requirements
- To determine equipment depreciation schedules
Correct answer: To provide a reference for quantifying savings after implementation
A baseline documents pre-retrofit energy use so that post-implementation consumption can be compared to quantify actual savings achieved.
Question 3: A CEM is developing an energy master plan. Which element is MOST critical to include for long-term strategic success?
- A single-year equipment replacement list
- Aligned energy goals with organizational mission and capital planning cycles (Correct answer)
- Only utility bill cost projections
- Equipment manufacturer warranty schedules
Correct answer: Aligned energy goals with organizational mission and capital planning cycles
An effective energy master plan integrates energy goals with organizational priorities and budget cycles to ensure sustained commitment and funding.
Question 4: Which strategy is MOST effective for managing electricity costs associated with time-of-use (TOU) rates?
- Installing power factor correction capacitors
- Shifting non-critical loads to off-peak hours (Correct answer)
- Increasing connected load during peak periods
- Renegotiating the service voltage level
Correct answer: Shifting non-critical loads to off-peak hours
Under TOU rates, electricity costs more during peak hours, so shifting flexible loads — like chilling, laundry, or charging — to off-peak periods directly reduces bills.
Question 5: An energy manager discovers that a chiller plant is running at 15% load most of the time. What strategy should be evaluated FIRST?
- Add a fourth chiller to improve redundancy
- Stage chillers so fewer machines run at higher, more efficient loads (Correct answer)
- Replace all chillers with higher-capacity units
- Reduce chilled water setpoint temperature
Correct answer: Stage chillers so fewer machines run at higher, more efficient loads
Chillers operate most efficiently near 80–90% of their design load; staging fewer units at higher loads eliminates the severe efficiency penalty of part-load operation.
Question 6: What is 'retrocommissioning' (RCx) as an energy management strategy?
- Installing new high-efficiency equipment to replace old systems
- Systematically tuning existing building systems to restore or exceed original design performance (Correct answer)
- Commissioning renewable energy systems after installation
- Decommissioning end-of-life equipment safely
Correct answer: Systematically tuning existing building systems to restore or exceed original design performance
Retrocommissioning investigates and corrects faults in existing systems — such as controls drift, sensor errors, and scheduling problems — without capital replacement.
Question 7: A CEM wants to benchmark a hospital's energy performance. Which tool is MOST appropriate for US facilities?
- ISO 50001 gap assessment checklist
- ENERGY STAR Portfolio Manager (Correct answer)
- ASHRAE 90.1 prescriptive compliance path
- LEED energy credit calculator
Correct answer: ENERGY STAR Portfolio Manager
ENERGY STAR Portfolio Manager provides 1–100 energy performance scores normalized for weather and occupancy, enabling apples-to-apples comparison with similar US facilities.
CEM Methods and Strategies 3
Which measurement and verification (M&V) option under IPMVP is MOST appropriate when it is difficult to isolate individual measure savings?