Incandescent Lighting

incandescent lightingIncandescent lighting is the most common type of lighting used in homes. It has traditionally delivered about 85% of household illumination.

Incandescent lamps operate without a ballast. They light up instantly, providing a warm light and excellent color rendition. You can also dim them. However, incandescent lamps have a low efficacy compared to other lighting options (10–17 lumens per watt) and a short average operating life (750–2500 hours).

Incandescent lamps are the least expensive to buy. However, because of their relative inefficiency and short life spans, they usually are more expensive to operate. The incandescent lamp is the oldest and most common type of lamp. Light is emitted when electricity flows through—and heats—a tungsten filament.

Types of Incandescent Lamps

These are the three most common types of incandescent lamps:

  • Standard incandescent lamps
  • Tungsten halogen lamps
  • Reflector lamps

You can use the chart below to compare these types of lamps. This chart can help you understand basic lighting principles and terms.

Incandescent Lighting Type

Efficacy
(lumens/watt)

Lifetime
(hours)

Color Rendition Index
(CRI)

Color Temperature
(K)

Indoors/Outdoors

Standard “A” bulb

10–17

750–2500

98–100 (excellent)

2700–2800 (warm)

Indoors/outdoors

Tungsten halogen

12–22

2000–4000

98–100 (excellent)

2900–3200 (warm to neutral)

Indoors/outdoors

Reflector

12–19

2000–3000

98–100 (excellent)

2800 (warm)

Indoors/outdoors