Lighting puts a big dent in average energy consumption. In residential buildings, lighting accounts for 11% of energy usage. In commercial buildings, lighting energy use jumps to 18%. To cut back on these costs, more efficient lighting technology such as LEDs is becoming more popular. Here are some guidelines that determine light efficiency.
Efficacy
A major component in understanding light efficiency is understanding luminous efficacy. A lumen is the total amount of light that a light source emits. Luminous efficacy indicates the ability of a light source to emit visible light using a given amount of power. This measurement is referred to as lumens per watt, and it’s determined by dividing the lumens by the watts (or power) of a given light source.
Other Factors That Affect Lighting Efficiency
Luminous efficacy is the most important factor in lighting efficiency, but a few other features play a role in determining the most efficient light sources.
Cost and Life Span
In a comparison between incandescent bulbs and LED bulbs, you’ll most likely discover that LEDs have greater luminous efficacy. However, you may also notice their price is slightly higher, which may cause you to second-guess whether the efficacy is worth it. This is where life span comes into play. LEDs have a significantly longer life span than other bulb types, making the initial upfront cost well worth the investment and increasing their efficiency.
Environmental Impact and Energy Usage
Energy-efficient lights can further decrease the amount of energy needed to produce quality, efficient lighting. Lighting choices such as industrial LED outdoor lighting and other LED bulb types are free of mercury, and they don’t use heat when converting energy to light. These factors reduce the amount of energy used without disrupting the amount of light the bulbs give off, further reducing costs without reducing efficiency.
Understanding luminous efficacy is the heart of understanding light efficiency, although the cost, life span, environmental impact, and energy usage all affect light efficiency as well.