CEM Cheat Sheet 2026

The 30 highest-yield CEM facts, distilled from real exam questions. Print it, save it as a PDF, or study it here — free, no sign-up.

1. In an energy audit report, which financial metric accounts for the time value of money? → Net Present Value (NPV)
2. A variable frequency drive (VFD) on a pump or fan saves energy because fan/pump power varies with: → The cube of speed
3. A wind turbine's power output varies with wind speed according to: → A cubic relationship (power ∝ speed³)
4. Utility rebates for energy efficiency projects are typically classified as: → Non-recurring benefits that reduce the net capital cost of the project
5. Degree days are used in building energy analysis to: → Quantify heating or cooling demand based on outdoor temperature deviation from a base
6. What does the Color Rendering Index (CRI) measure? → How accurately a light source renders colors compared to a reference source
7. What is the significance of the motor's insulation class designation (e.g., Class F, Class H)? → Maximum continuous winding temperature the insulation can withstand
8. Thermal energy storage (TES) paired with a chiller plant saves energy cost (not necessarily energy) by: → Shifting chiller operation to off-peak hours when electricity rates are lower
9. When comparing natural gas cost ($/MMBtu) to electricity cost ($/kWh) for energy analysis, the correct conversion factor is: → 1 kWh = 3,412 Btu
10. Net metering allows facilities with on-site generation to: → Credit excess electricity fed back to the grid against future consumption charges
11. In a thermal energy storage (TES) system used for demand-side management, the 'discharge' period typically occurs: → During on-peak hours when cooling loads are highest
12. In an Energy Savings Performance Contract (ESPC), the contractor's payment is primarily based on: → Verified energy savings achieved after implementation
13. The Investment Tax Credit (ITC) for solar energy systems in the US allows eligible projects to: → Claim a percentage of the installation cost as a direct federal income tax credit
14. During an energy audit, the auditor identifies that a facility's power factor averages 0.78. What is the MOST likely financial consequence? → Power factor penalty on the utility bill
15. A Direct Digital Control (DDC) system differs from pneumatic controls primarily because it: → Uses digital microprocessors and electronic sensors for precise, programmable control
16. When evaluating electricity bills for demand charge reduction opportunities, which interval data granularity provides the MOST actionable insight? → 15-minute interval demand data
17. An energy audit of a motor-driven system should calculate energy savings from a VFD based on the: → Reduction in shaft speed raised to the third power, per the Affinity Laws
18. High-pressure sodium (HPS) lamps are commonly used in street lighting because they offer: → High efficacy and long lamp life
19. A system of electricity has 52.9 kVA and 50.5 kW. To get the power factor of the entire load to 95%, how many kVARs of capacitance are needed? → 0 kVARs
20. The Modified Accelerated Cost Recovery System (MACRS) is used in energy project financial analysis to: → Determine tax depreciation deductions over the asset's recovery period
21. The US industries and structures with the highest installation rates of electric motors are: → AC Induction
22. The 'boiler horsepower' (BHP) unit is defined as: → The ability to evaporate 34.5 lb/hr of water from and at 212°F
23. A building energy benchmark using ENERGY STAR Portfolio Manager allows a facility manager to: → Compare the building's energy performance against similar buildings nationally
24. The primary purpose of a vestibule (airlock entry) in a commercial building is to: → Reduce infiltration by preventing direct outdoor air connection when doors open
25. An energy project requires a $100,000 investment and generates $25,000 in annual savings over a 10-year life. What is the simple Return on Investment (ROI)? → 150%
26. What does a motor's service factor (SF) indicate? → The permissible continuous overload multiplier above nameplate rating
27. LED lighting saves energy over fluorescent primarily because it: → Converts more electrical energy to light with less heat loss
28. Heat recovery systems (also known as heat exchangers) are unable to lower temperatures below the hot gas's dew point. → False
29. The 'avoided cost' of energy is most accurately described as: → The cost savings that result from not consuming a unit of energy
30. An M&V plan following IPMVP Option B (Retrofit Isolation with Short-Term Measurement) requires: → Metering only the retrofitted system using short-term post-retrofit measurements