CEA Energy Auditing & Assessment Techniques 5

Question 1

In an energy audit context, 'phantom loads' (also called standby or vampire loads) refer to:

Accepted Answer

Energy consumed by plug-in devices while switched off or in standby mode

Answer

Phantom loads can account for 5–10% of residential and small commercial electricity use; smart power strips and occupancy-based controls reduce them.

Question 2

An energy auditor recommends a variable frequency drive (VFD) on a constant-volume pump. The energy savings potential follows the affinity laws, meaning a 20% speed reduction yields approximately:

Accepted Answer

49% reduction in power consumption (cube law relationship)

Answer

Per the affinity laws, pump power varies with the cube of speed: (0.80)³ = 0.512, meaning a 20% speed reduction reduces power by approximately 49%.

Question 3

When reviewing a building's energy model during an audit, the auditor finds that the simulated EUI closely matches the actual utility EUI. This means the model is:

Accepted Answer

Calibrated and can be used to reliably predict savings from proposed energy conservation measures

Answer

A calibrated energy model that matches actual utility data is a reliable tool for predicting ECM savings and is the foundation of investment-grade (Level III) audits.

Question 4

A 'short-circuit factor' in duct leakage testing refers to:

Accepted Answer

Supply air leaking directly into return air pathways before conditioning occupied spaces

Answer

Supply-to-return duct leakage short-circuits conditioned air, reducing HVAC effectiveness and forcing the system to work harder to maintain setpoints.

Question 5

During a renewable energy feasibility assessment as part of an energy audit, which factor is MOST critical in evaluating a rooftop solar PV installation?

Accepted Answer

Roof orientation, tilt angle, and shading analysis to determine annual solar irradiance

Answer

Solar resource quality—determined by orientation, tilt, and shading—directly governs PV system output and is the primary technical determinant of project viability.

(CEA) Certified Energy Analyst Practice Test

(CEA) Certified Energy Analyst Practice Test

CEA Energy Auditing & Assessment Techniques 5