NABCEP Energy Efficiency & Conservation Techniques 5

Question 1

The 'negawatt' concept in demand-side management refers to:

Accepted Answer

A unit of electrical power capacity saved through efficiency or conservation

Answer

A negawatt represents one megawatt of power that has been saved through efficiency improvements, treated as equivalent to a megawatt of new generation capacity.

Question 2

Which climate-responsive design strategy uses high-mass exterior walls that absorb daytime solar heat and re-radiate it into living spaces at night?

Accepted Answer

Trombe wall

Answer

A Trombe wall is a south-facing masonry or concrete wall with glazing that absorbs solar heat during the day and releases it indoors in the evening.

Question 3

An energy model predicts a building's annual energy use. Which input change would most directly reduce predicted heating energy in a cold climate?

Accepted Answer

Improving window U-factor from 0.45 to 0.22

Answer

Halving the window U-factor dramatically reduces conductive heat loss through the windows, which is a major heating load driver in cold climates.

Question 4

Which energy efficiency measure typically has the shortest simple payback in residential buildings?

Accepted Answer

Air sealing accessible penetrations (attic, basement)

Answer

Air sealing is low-cost and labor-light, often yielding 10–30% heating/cooling savings with paybacks of 1–3 years, outperforming capital-intensive measures.

Question 5

A peak demand charge on a commercial utility bill is based on:

Accepted Answer

The highest average power demand measured during any 15- or 30-minute interval in the billing period

Answer

Demand charges are assessed based on the single highest demand interval (often 15 minutes) in the month, incentivizing load leveling and peak reduction strategies.

(NABCEP) Certified North American Board of Certified Energy Practitioners Specialist Practice Test

(NABCEP) Certified North American Board of Certified Energy Practitioners Specialist Practice Test

NABCEP Energy Efficiency & Conservation Techniques 5