Which statement best describes LED energy efficiency relative to incandescent and fluorescent lighting?

Which statement best describes LED energy efficiency relative to incandescent and fluorescent lighting?

• A. It is less energy-efficient than incandescent
• B. It is not used in many applications
• C. It is about the same as fluorescent
• D. It is more energy-efficient than incandescent and can be more energy-efficient than most fluorescent lamps

Answer: (D)

LEDs convert most of the electrical power into light rather than heat, giving them a higher efficacy (lumens per watt) than incandescent bulbs. Incandescent lighting is very inefficient because much of the energy becomes heat, not usable light. Fluorescent lamps are more efficient than incandescent, but LEDs typically deliver more light per watt than most fluorescent lamps. Therefore, LEDs are generally more energy-efficient than incandescent and can be more energy-efficient than most fluorescent lamps, which is why this statement is the best description. In practice, efficacy numbers vary by specific LED and fluorescent technology, but the overall trend holds: LEDs use less power for the same light output.

LEDs convert most of the electrical power into light rather than heat, giving them a higher efficacy (lumens per watt) than incandescent bulbs. Incandescent lighting is very inefficient because much of the energy becomes heat, not usable light. Fluorescent lamps are more efficient than incandescent, but LEDs typically deliver more light per watt than most fluorescent lamps. Therefore, LEDs are generally more energy-efficient than incandescent and can be more energy-efficient than most fluorescent lamps, which is why this statement is the best description. In practice, efficacy numbers vary by specific LED and fluorescent technology, but the overall trend holds: LEDs use less power for the same light output.