CEM - Certified Energy Manager Energy Audits and Instrumentation Questions and Answers

Question 1

An energy auditor is conducting a walkthrough of a commercial building and notices that a large motor is operating continuously.
To assess the electrical efficiency of this motor, which two measurements are most crucial for calculating the power factor?

Accepted Answer

Real power (kW) and apparent power (kVA)

Answer

Voltage and current

Answer

Resistance and capacitance

Answer

Runtime hours and motor nameplate horsepower

Question 2

During an ASHRAE Level 2 energy audit of a manufacturing facility, which of the following activities would be most characteristic of this audit level?

Accepted Answer

A detailed breakdown and analysis of energy consumption by end-use, with financial analysis of recommended measures.

Answer

A simple walkthrough to identify obvious low-cost energy saving opportunities.

Answer

A detailed whole-building computer simulation to model complex capital-intensive retrofits.

Answer

A review of utility bills and a brief site survey to establish a baseline.

Question 3

An energy manager is tasked with identifying specific locations of heat loss and insulation deficiencies in a building's envelope. Which instrument is best suited for this purpose?

Accepted Answer

Infrared Camera (Thermography)

Answer

Blower Door

Answer

Ultrasonic Leak Detector

Answer

Hygrometer

Question 4

To determine the combustion efficiency of a natural gas boiler and ensure its safe operation, an energy auditor should use which of the following instruments?

Accepted Answer

Combustion Analyzer

Answer

Pitot Tube

Answer

Power Quality Analyzer

Answer

Light Meter

Question 5

An energy audit of a compressed air system is planned. The primary goal is to identify and quantify costly leaks. Which instrument would be most effective for locating these leaks while the system is operational?

Accepted Answer

Ultrasonic Leak Detector

Answer

Anemometer

Answer

Manometer

Answer

Stroboscope

Question 6

Which of the following scenarios would justify the cost and effort of an ASHRAE Level 3 audit?

Accepted Answer

A university campus planning a multi-million dollar central plant renovation with major HVAC system replacements.

Answer

A small retail store looking for simple, no-cost ways to reduce its monthly utility bill.

Answer

A facility manager needing to create an initial energy use baseline and identify obvious areas of waste.

Answer

A commercial office building that has just completed a lighting retrofit and wants to verify the savings.

An energy auditor is conducting a walkthrough of a commercial building and notices that a large motor is operating continuously.To assess the electrical efficiency of this motor, which two measurements are most crucial for calculating the power factor?

An energy auditor is conducting a walkthrough of a commercial building and notices that a large motor is operating continuously.
To assess the electrical efficiency of this motor, which two measurements are most crucial for calculating the power factor?