[Sep 19, 2025] Free AEE CEM Exam Questions and Answer
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NEW QUESTION # 23
Which of the following statements regarding refrigerants is NOT correct?
5ELECT THE CORRECT ANSWER
- A. R-32 and R-134a are Hydro Fluoro Carbons with zero ozone depleting potential, and significant global warming impact
- B. R-22 is a Hydro Chloro Carbon with significant ozone depleting potential and significant global warming impact
- C. R-1234yf is a Hydro Fluoro Olefin with zero ozone depleting potential, and little global warming potential
- D. R-11 and R-12 are Chloro Fluoro Carbons with significant ozone depleting potential
- E. R-407C is a blended Hydro Fluoro Carbon or near Azeotropic mixture, and can be used as a replacement for R-22 in commercial applications
Answer: B
Explanation:
Understanding the environmental impacts of various refrigerants is crucial for energy managers. Let's analyze each statement:en.wikipedia.org A:R-407C is a blended Hydro Fluoro Carbon or near Azeotropic mixture, and can be used as a replacement for R-22 in commercial applications:This statement is correct. R-407C is a blend of HFCs designed to replace R-22 in air conditioning systems.
B:R-11 and R-12 are Chloro Fluoro Carbons with significant ozone depleting potential:This is correct. R-
11 and R-12 are CFCs known for their high ozone depletion potential.
C:R-1234yf is a Hydro Fluoro Olefin with zero ozone depleting potential, and little global warming potential:Correct. R-1234yf is an HFO with negligible ozone depletion and low global warming potential.
D:R-22 is a Hydro Chloro Carbon with significant ozone depleting potential and significant global warming impact:This statement is incorrect.R-22 is a Hydrochlorofluorocarbon (HCFC), not a Hydro Chloro Carbon.While it does have ozone-depleting potential, its global warming potential is considered moderate, not significant.
E:R-32 and R-134a are Hydro Fluoro Carbons with zero ozone depleting potential, and significant global warming impact:This is correct. Both R-32 and R-134a are HFCs with no ozone depletion potential but have considerable global warming potential.
Conclusion:
The incorrect statement is D. R-22 is a Hydro Chloro Carbon with significant ozone depleting potential and significant global warming impact. Therefore, the correct answer is D.
NEW QUESTION # 24
Periodic commissioning of a building automation system (BAS) might include which of the following?
- A. Verify controls are still responsive to the BAS
- B. All of the above
- C. Answers A and C
- D. Retraining staff on the BAS functions and programming
- E. Removing temperature set point overrides
Answer: B
NEW QUESTION # 25
If a boiler cycles on and off too frequently, what control can you adjust to reduce the number of times a boiler cycles on and off?
- A. Increase the controller differential
- B. Increase the controller set point
- C. Reduce the controller differential
Answer: A
NEW QUESTION # 26
A new lighting system costs $60,000. The new lighting system has a 15-year life and the minimum required rate of return (MARR) is 15%. How much must the new lighting system save to be life-cycle cost effective?
- A. $33,200/year
- B. $12,556/year
- C. $15,650/year
- D. $10,260/year
- E. $27,090/year
Answer: B
NEW QUESTION # 27
Which of the following is NOT a renewable-energy resource?
SELECT THE CORRECT ANSWER
- A. Saw grass
- B. Ocean waves
- C. Shale gas
- D. Crop residue
- E. Geothermal heat
Answer: C
Explanation:
Renewable energy resources are naturally replenished on a human timescale. Let's evaluate each option:
A:Saw grass:A biomass resource, renewable through regrowth.
B:Shale gas:A fossil fuel extracted from shale formations, non-renewable.
C:Geothermal heat:Energy from Earth's internal heat, renewable.
D:Ocean waves:Mechanical energy from ocean surface waves, renewable.
E:Crop residue:Organic materials from agriculture, renewable.
Conclusion:
Shale gas is not a renewable energy resource. Therefore, the correct answer is B.
NEW QUESTION # 28
Thermal scans of electrical equipment are useful for:
- A. Measuring the load on a refrigerant system
- B. Locating a loose electrical connection
- C. Reading current carrying capacity of installed conductors
- D. Locating areas of high power factor
Answer: B
Explanation:
Step 1: Purpose of Thermal Scans
Thermal scans (infrared thermography) detecttemperature variationsin electrical components.
* Loose connectionsincrease resistance # causeoverheating, which isvisible in thermal scans.
Step 2: Analysis of Each Option
* A. Locating areas of high power factor#Incorrect#Power factor is measured with power meters.
* B. Reading current-carrying capacity of conductors#Incorrect#Measured using ammeters and engineering data.
* C. Locating a loose electrical connection#Correct#Loose connections causeheat buildup, easily detected with thermal scans.
* D. Measuring the load on a refrigerant system#Incorrect#Refrigerant loads are measured using pressure sensors and flow meters.
Thus, the correct answer isC. Locating a loose electrical connection.
NEW QUESTION # 29
What is the purpose of top (or skimming) blowdown in a steam boiler?
- A. To flush out the boiler room drain system
- B. To reduce the buildup of sediment in the boiler
- C. To reduce the buildup of feedwater chemicals in the boiler
- D. To dilute the level of impurities in the boiler water thus allowing the addition of cleaner make up water
Answer: C
NEW QUESTION # 30
How much energy (kJ) is required to heat 2 kg of water from 25°C to 2 kg of water at 100°C? (The specific heat of water (C) is 4.2 kJ/kg-°C. Assume no system losses.)
- A. 420 kJ
- B. 630 kJ
- C. 840 kJ
- D. 510 kJ
Answer: C
NEW QUESTION # 31
An energy project implemented today saves $10,000 per year for the next 20 years. Using the 5% interest table, determine the total value of savings at the end of the 20th year?
- A. $330,660
- B. $496,991
- C. $146,907
- D. $124,620
- E. $200,000
Answer: B
NEW QUESTION # 32
What term describes the difference between the control signal value and the set point?
- A. Cut off
- B. Error or offset
- C. Differential
- D. Dead band
- E. Dead time
Answer: B
NEW QUESTION # 33
What is the main reason for using instrumentation in energy audits?
- A. Support the local economy
- B. Save energy
- C. Validate utility energy bills
- D. Determine energy flows
Answer: D
Explanation:
Instrumentation in energy audits serves multiple functions, but theprimary reasonis to determine energy flows.
* Measuring Energy Flows:
* Instrumentation helpsquantify energy usein different systems, such as electricity, HVAC, and industrial processes.
* It helps identifywhere energy is used, lost, or wasted.
* Supporting Energy Conservation Efforts:
* By measuring energy flows, auditors canidentify inefficienciesand recommend solutions.
* Other Options Analysis:
* Saving energy (A):A result of energy audits, not the main purpose.
* Validating utility bills (C):Important but secondary to understanding energy flows.
* Supporting the local economy (D):Not relevant.
Thus, the correct answer isB. Determine energy flows.
NEW QUESTION # 34
Which of the following controls can optimize the operation of lighting systems?
- A. All of the above
- B. Timer
- C. Dimming ballasts
- D. Photocells
- E. Occupancy sensors
Answer: A
NEW QUESTION # 35
What type of heat transfer is reduced by adding insulation to the inside surface of a wall?
- A. Radiation
- B. Convection
- C. Conduction
Answer: C
NEW QUESTION # 36
A 50-Hz alternating current (AC) induction motor has 3 pole pairs (6 poles). What is the synchronous speed of the motor?
- A. 750 rpm
- B. 1,000 rpm
- C. 600 rpm
- D. 1,500 rpm
Answer: D
NEW QUESTION # 37
Using the lumen method, calculate the number of luminaires (fixtures) required to light a room to 200 lux.
Each luminaire has 2 fluorescent lamps, 3,000 lumens per lamp. The room is 20 meters by 30 meters. The total light loss factor (LLF) is 0.70 and the luminaire coefficient of utilization (CU) is 0.80.
- A. 60 luminaires
- B. 48 luminaires
- C. 12 luminaires
- D. 36 luminaires
- E. 24 luminaires
Answer: E
NEW QUESTION # 38
A desk lamp is located inside a windowless office. The office is heated during the winter and cooled during the summer. When the lamp is switched on, how much of the energy consumed by the lamp becomes heat in the office space?
- A. 120%
- B. 100%
- C. 25%
- D. 80%
Answer: B
Explanation:
* All electrical energy consumed by the lamp is converted into heatwithin the space, either as direct heat or as waste heat from the light source.
* In a windowless office, no energy escapes as light.The light energy that is emitted eventually turns into heat through absorption by surfaces.
Thus, the correct answer isC. 100%.
NEW QUESTION # 39
Which of the following is NOT a typical benefit of performance contracting from the building owner's perspective?
- A. The energy-service company can have a financial incentive to achieve projected savings
- B. Net cash flow can be neutral or positive for the owner
- C. Maintenance services provided by the performance contractor can add value to the overall savings achieved
- D. Performance contracting can provide access to external financing when the owner may not have sufficient equity for in-house financing for large projects
- E. Performance contracting is a simple and quick process
Answer: E
NEW QUESTION # 40
A fully-loaded heat pump unit delivers 36-kW thermal heating with a power draw of 12-kW electric. What is the coefficient of performance (COP) at full load?
- A. 2.0
- B. 5.0
- C. 4.0
- D. 3.0
- E. 6.0
Answer: C
NEW QUESTION # 41
Why do electric utility companies transmit power at high voltages?
SELECT THE CORRECT ANSWER
- A. Higher voltages are more stable
- B. Electrical frequency is more stable
- C. Transmission power losses (12R) are less
- D. Higher voltages are safer
Answer: C
Explanation:
Electric utility companies transmit power at high voltages primarily to reduce transmission power losses, which are proportional to the square of the current (I²) multiplied by the resistance (R) of the transmission lines. This relationship is expressed by the formula for power loss: P_loss = I²R.
Key Points:
* Power Loss and Current Relationship:Power losses in transmission lines are directly proportional to the square of the current flowing through them. Reducing the current decreases these losses significantly.
* High Voltage Transmission:By increasing the transmission voltage, the current required to deliver the same amount of power decreases. This is because power (P) is the product of voltage (V) and current (I): P = VI. For a given power level, increasing voltage allows for a corresponding decrease in current.
* Reduced I²R Losses:Lower current results in reduced I²R losses, enhancing the efficiency of power transmission over long distances.
Conclusion:
Transmitting power at high voltages minimizes transmission losses, making it the most efficient method for long-distance electrical power delivery. Therefore, the correct answer is C. Transmission power losses (I²R) are less.
NEW QUESTION # 42
How does an enthalpy-based economizer control operate?
- A. Using a constant mixed air proportion control sequence
- B. Using the dry-bulb temperature and relative humidity of both the outdoor-air and return-air
- C. Comparing the difference in dry-bulb air temperature measurements of the return air and the outdoor air
- D. Measuring the outdoor air dry-bulb temperature and relative humidity
Answer: B
NEW QUESTION # 43
What is a common method to reduce the impact of voltage imbalance?
- A. Install capacitors to improve power factor on three-phase loads
- B. Reverse phase connections on three-phase motors
- C. Install harmonic filters
- D. Rebalance single-phase loads
Answer: D
NEW QUESTION # 44
In a performance contract, which group has the greatest investment risk?
- A. Risk is shared by the terms in the performance contract
- B. The company installing the energy project
- C. The equipment manufacturer
- D. The energy-service company
Answer: D
NEW QUESTION # 45
The set point for the chiller supply water temperature is varied as a function of the thermal demand for space cooling. What do you call this control strategy?
- A. Night setback
- B. Reheat coil reset
- C. Chilled-water temperature reset
- D. Condenser-water temperature reset
Answer: C
NEW QUESTION # 46
An air-conditioning unit delivers 10,000 kJ/h (thermal cooling). The equipment uses single-phase electrical power at 220-volt and 5.25 amps with a power factor of 100%. Calculate the coefficient of performance (COP).
- A. 6.2
- B. 13.2
- C. 16.1
- D. 2.4
- E. 3.2
Answer: E
Explanation:
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NEW QUESTION # 47
An outdoor parking area has 25 light poles. Each pole has a 420 Watt (ballast included) high-pressure sodium (HPS) luminaire. The parking area lights are illuminated 4,500 hours per year and the electricity cost is $0.08
/kWh. What is the annual energy cost reduction if each luminaire is replaced with a 220-Watt (driver included) LED luminaire?
- A. $1,200/yr
- B. $1,800/yr
- C. $2,600/yr
- D. $2,200/yr
- E. $1,500/yr
Answer: B
Explanation:
To determine the annual energy cost savings from switching to LED luminaires:
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NEW QUESTION # 48
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