CEM Certified Energy Manager (CEM) Questions and Answers

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.

Monitoring energy consumption is a critical component of effective energy management. It serves multiple purposes that collectively enhance an organization's ability to control energy use, identify inefficiencies, and implement improvements. These purposes include:​

Establishing a Basis of Management Control:By systematically tracking energy consumption, organizations create a foundation for managing energy use effectively. This data enables the setting of benchmarks and performance indicators, facilitating informed decision-making and strategic planning.

Identifying Deviations in Energy Consumption Patterns:Continuous monitoring allows for the detection of anomalies or unexpected changes in energy usage. Recognizing when and why these deviations occur is essential for diagnosing potential issues, such as equipment malfunctions or operational inefficiencies, and addressing them promptly.

Supporting Analysis of Energy Information:Comprehensive energy data collection supports detailed analysis, aiding in understanding consumption trends, evaluating the impact of energy conservation measures, and identifying opportunities for further efficiency improvements.

Given that monitoring energy consumption fulfills all the above functions, the correct answer is D. All of the above.

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The Institute of Electrical and Electronics Engineers (IEEE) Standard 519, titled "Recommended Practices and Requirements for Harmonic Control in Electrical Power Systems," sets forth guidelines to maintain the quality of electrical power by limiting harmonic distortions. According to IEEE 519, for general low-voltage systems (defined as systems with a voltage less than 600 volts), the Total Harmonic Distortion (THD) of the voltage waveform should not exceed 5%. This threshold ensures the reliable operation of electrical equipment and minimizes potential issues such as overheating or malfunctioning caused by excessive harmonics. Therefore, the correct answer is C. Less than 5%.

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 usingpressure sensors and flow meters.

Thus, the correct answer isC. Locating a loose electrical connection.

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.

When conducting internal audits of an Energy Management System (EnMS) in accordance with ISO 50001, auditors are expected to perform several key activities to ensure the system's effectiveness and continual improvement. These activities include:​

Focus on Areas of Significant Energy Use:Auditors should prioritize auditing areas that have substantial energy consumption, as improvements in these areas can lead to significant energy performance enhancements.

Review Written Procedures Related to the Area Under Audit:A thorough examination of documented procedures ensures that they align with ISO 50001 requirements and organizational practices. This review helps in identifying any discrepancies between documented procedures and actual practices.

Assess Actual Activities Against Written Procedures:Auditors compare on-ground activities with documented procedures to verify compliance and identify deviations. This assessment ensures that operations are performed as intended and in line with established protocols.

Look for Opportunities for Energy Improvement and Minimize Bureaucracy:Identifying opportunities for enhancing energy performance is a core objective of the audit.Auditors should also aim to streamline the EnMS by reducing unnecessary complexities, thereby making it more efficient and user-friendly.

By encompassing all these activities, internal auditors ensure a comprehensive evaluation of the EnMS, leading to effective energy management and continual improvement. Therefore, the correct answer is E. All of the above.