BOC Energy Conservation Techniques 4

Question 1

Which ENERGY STAR Portfolio Manager metric is commonly used to benchmark a commercial building's annual energy performance?

Accepted Answer

Energy Use Intensity (EUI) in kBtu/ft²/yr

Answer

EUI normalizes total annual energy use by floor area so buildings can be compared.

Question 2

Air compressor systems often waste energy mainly through:

Accepted Answer

Leaks in distribution piping and fittings

Answer

Leaks can waste 20–30% of compressor output, so leak detection and repair is a key conservation measure.

Question 3

Optimal start control in a BAS saves energy by:

Accepted Answer

Calculating the latest start time needed to reach setpoint by occupancy

Answer

Optimal start uses space and outdoor conditions to start equipment just in time, which avoids unnecessary early runtime.

Question 4

Which lighting control is most suitable for perimeter offices with large windows?

Accepted Answer

Daylight harvesting with photosensors

Answer

Daylight harvesting dims electric lights in proportion to the natural light available near windows.

Question 5

Lowering condenser water supply temperature (within manufacturer limits) generally:

Accepted Answer

Improves chiller efficiency but may increase cooling tower fan energy

Answer

Cooler condenser water reduces compressor lift, but the tower fans may run harder, so the total plant energy has to be optimized.

BOC - Building Operator Certification Practice Test