CLC Energy Efficiency & Sustainability 3

Question 1

In daylighting design, what is the primary purpose of a light shelf?

Accepted Answer

To reflect daylight deeper into the building interior

Answer

A light shelf is a horizontal reflective surface that bounces daylight off the ceiling to illuminate areas farther from the window.

Question 2

Which metric is used to measure the potential of a building's daylit zones relative to all occupied hours with sufficient daylight?

Accepted Answer

Daylight Autonomy (DA)

Answer

Daylight Autonomy (DA) expresses the percentage of occupied hours when a point receives at least the target illuminance from daylight alone.

Question 3

A LED lamp has a rated life of 50,000 hours. Operating 12 hours per day, approximately how many years will it last?

Accepted Answer

11 years

Answer

50,000 hours ÷ (12 hrs/day × 365 days/year) ≈ 11.4 years.

Question 4

What is the primary environmental benefit of reducing lighting energy consumption in a building connected to a coal-heavy electrical grid?

Accepted Answer

Reduced CO₂ emissions from power generation

Answer

Coal power plants emit significant CO₂; reducing electricity demand directly lowers greenhouse gas emissions at the generation source.

Question 5

Which type of dimming control maintains constant light output over a lamp's life by increasing power as lumens depreciate?

Accepted Answer

Lumen maintenance dimming

Answer

Lumen maintenance dimming starts fixtures at reduced output and increases drive current over time to compensate for lumen depreciation, saving energy early in lamp life.

(CLC) Certified Lighting Consultant Practice Test

(CLC) Certified Lighting Consultant Practice Test

CLC Energy Efficiency & Sustainability 3