One of the biggest features attributed to LED technology is a bulb’s ability to use energy efficiently. To ensure we’re on the same page, the efficiency of a lamp refers to its ability to produce a specific amount of light relative to the amount of energy it uses. Generally, the less energy used to produce a given amount of light, the more efficient the lamp. Western countries in particular are pushing higher efficiency as a way to reduce energy use—especially the use of fossil fuels to generate electricity. Some European nations have gone so far as to ban incandescent lamps due to their poor efficiency (along with halogens) relative to LEDs.

Many LED lamps now match or exceed the efficiency of CFLs and fluorescent tubes; however, many don’t. These under-performers are typically the extremely low-priced lamps sold at discount stores and on the Internet.

So what determines efficiency?

With an LED lamp, overall efficiency depends in part on the tiny semiconductor chip inside. It runs on low voltage direct current (DC), not higher voltage alternating current (AC), so each lamp requires a power supply to convert the AC power in the socket to the DC power needed to drive the LED. Currently, the average power supply is about 70% to 85% efficient, which means about 15% to 30% of the power is lost converting it to DC.

Efficiency also depends on the optics—the lens that directs and focuses the light. Generally, LED lamp optics are approximately 85% to 90% efficient.

So LED lamps aren’t 100% efficient, but no lighting types are. Look at it this way: compared to incandescent and halogen bulbs, LED lamps typically generate the same amount of light using approximately 10% to 15% of the energy. That means that the average incandescent bulb wastes 85% to 90% of the energy it uses! Take into account the long life of LED lamps and LEDs emerge the clear choice for anyone who wants to reduce energy consumption, save money on their energy bills, and reduce greenhouse-gas emissions related to power generation.

Will LED-lamp efficiency improve?

Undoubtedly. The chip, power supply, and optics are three of the most important aspects of LED lighting technology, subject to continual and intense research and design. Major advances occur every few months, suggesting LED lamps will soon outperform all other lighting types when it comes to efficiency. Increased efficiency is certain to boost uptake among consumers, who already consider energy savings to be one of the most attractive features of LED lighting technology.

Is energy efficiency a big part of the reason you are attracted to LED bulbs? Does the relatively high cost of LED bulbs concern you—even though you’ll see a return on investment through reduced energy use? Let us know!