Incandescent light bulbs are not energy-efficient because they produce light by heating a filament until it glows, which wastes a lot of energy.

LEDs (light-emitting diodes) have a lifespan of up to 50,000 hours and are very energy-efficient, using up to 85% less energy than incandescent bulbs.

CFLs are more energy-efficient than incandescent bulbs, using up to 75% less energy to produce the same amount of light.

LEDs are often used in streetlights and outdoor lighting because they are energy-efficient, durable, and can withstand harsh weather conditions.

Luminous efficacy is a measure of how efficiently a light source converts electrical energy into visible light.

Energy-efficient lighting can help to reduce light pollution by emitting less stray light and directing light more effectively.

The color rendering index (CRI) is a measure of how well a light source reproduces the colors of objects compared to natural sunlight.

Correlated color temperature (CCT) is a measure of the color appearance of a light source, ranging from warm (yellowish) to cool (bluish) light.

Beam angle is a measure of the angle at which a light source emits light, which affects the spread and directionality of the light.

Incandescent dimmers are not energy-efficient lighting control systems because they simply reduce the voltage to the bulb, which does not save energy as efficiently as other methods.

Occupancy sensors save energy by automatically turning off lights when a space is unoccupied, reducing energy waste.

Daylight sensors save energy by reducing the need for artificial lighting during the day, improving occupant comfort, and reducing eyestrain.

Beam angle is a measure of the angle at which a light source emits light, which affects the spread and directionality of the light.

Incandescent light bulbs are not energy-efficient because they produce light by heating a filament until it glows, which wastes a lot of energy.

OLEDs are thinner and more flexible than LEDs, making them suitable for use in a wider range of applications.