CEA Energy Auditing & Assessment Techniques 4

Question 1

When conducting an energy audit on a data center, which metric is used to assess overall infrastructure energy efficiency?

Accepted Answer

Power Usage Effectiveness (PUE)

Answer

PUE = Total Facility Power ÷ IT Equipment Power; a PUE of 1.0 is ideal, meaning all energy goes to IT loads with zero overhead.

Question 2

An energy auditor discovers that a chiller is operating at a COP of 2.8, while the manufacturer's rated COP at design conditions is 5.2. The MOST LIKELY cause is:

Accepted Answer

Fouled condenser tubes increasing condensing temperature and reducing heat transfer

Answer

Fouled condenser tubes raise condensing temperature, significantly degrading chiller COP; tube cleaning is a high-ROI maintenance measure.

Question 3

In an industrial facility audit, 'pinch analysis' is used to:

Accepted Answer

Identify the minimum heating and cooling energy required by optimizing heat exchanger network design

Answer

Pinch analysis identifies thermodynamic limits on heat recovery and targets opportunities to maximize heat exchanger integration, reducing external heating/cooling demand.

Question 4

A commercial building energy audit reveals a power factor of 0.72. What is the energy management implication?

Accepted Answer

The facility may incur utility power factor penalty charges and should add capacitor banks to correct it

Answer

Low power factor (below 0.90–0.95) causes utilities to charge penalties; capacitor banks or VFDs can correct power factor and eliminate surcharges.

Question 5

During a steam system audit, an auditor uses an ultrasonic detector and finds multiple steam traps that are 'blowing through.' This indicates:

Accepted Answer

Failed-open traps that are wasting live steam, a major energy loss requiring immediate replacement

Answer

Traps that blow through are failed-open, continuously venting live steam rather than only condensate, and represent significant direct energy waste.

(CEA) Certified Energy Analyst Practice Test

(CEA) Certified Energy Analyst Practice Test

CEA Energy Auditing & Assessment Techniques 4