How LED Lighting Works
Would you like to reduce the amount of electricity required to light your home or commercial building? LED lighting is an energy efficient, long lasting alternative to fluorescent and incandescent lighting.
LEDs, or light-emitting diodes, have long been used in electronic devices and home appliances. Because of their significant advantages over conventional lighting, LED light bulbs are now used to light offices, industrial buildings and modern homes.
Are you interested in learning more about how LED lighting works, and how using LEDs can reduce your building’s power consumption? Read on to learn more about this exciting, highly effective and energy efficient lighting technology.
How LED lighting works
LED lighting uses light-emitting diodes, placed inside a light bulb, to provide bright, steady and consistent light for a building’s interior.
Because LEDs have a longer lifespan than fluorescent and incandescent bulbs, they have become increasingly popular as a lighting option. LED light bulbs also use less energy than incandescent and fluorescent light bulbs, making them cheaper to use.
Most people are familiar with the coloured LEDs – typically red, blue or green – that are widely used in electronic devices. Instead of emitting coloured light, LED lighting emits white light to provide comfortable, functional lighting for interior spaces.
Emitting white light from an LED is a surprisingly challenging process. Modern LED light bulbs typically mix red, blue and green light together from several LEDs placed extremely close to each other to create consistent white light.
Unlike incandescent or fluorescent lights, which emit light in all directions, the light from LED light bulbs is directional. Most LED light bulbs used in homes and offices use a diffuser or an arrangement of multiple LEDs to provide non-directional light.
Understanding light-emitting diodes
From circuit boards to consumer electronics, LEDs are widely used in gadgets and appliances. Only recently have LEDs been used to provide a long-lasting, durable and energy efficient source of light for buildings and homes.
Light-emitting diodes, or LEDs, work extremely efficiently to create light. An LED is lit up by an electrical current, which passes through a semiconductor (in the case of a typical LED, aluminium-gallium-arsenide) and lights the diode.
One advantage of LEDs is that, unlike incandescent light bulbs, they typically don’t become hot during operation. This is because LEDs use a heat sink to absorb heat that’s produced in the process of creating light.
While the light created by LED light bulbs is white, there actually aren’t any white LEDs available. Most LED light bulbs use phosphor to change the light’s colour, or are placed close to each other to create a consistent stream of white light.
One big advantage of LED lighting is that LEDs don’t contain a filament. This means that they can’t “burn out” over time like fluorescent or incandescent lights, making them a more durable and dependable option for home and commercial use.
The chips used in LEDs require direct current electricity in order to operate. Most LED lighting installations use a circuit to convert the AC power available from the electrical socket or supply into a steady direct current for use in LED lighting.
How efficient is LED lighting?
One of the biggest benefits of LED lighting is that it’s significantly more efficient than other forms of lighting, such as incandescent or fluorescent light. Overall, LEDs use a significantly lower amount of electricity to produce light than other light bulbs.
A 100-200 watt tungsten incandescent light bulb has an overall luminous efficiency rating of 16.7 to 19.8 lumens per watt (lm/W). A typical 9–32 watt fluorescent light bulb has an overall luminous efficiency rating of 46 to 75 lm/W.
A 6.9 watt LED light with a screw base, designed for installation in a commercial or residential building’s ceiling, on the other hand, has an overall luminous efficiency rating of between 55.1 and 81.9 lm/W.
Expressed as a percentage, the overall luminous efficiency of a standard 6.9 watt LED light bulb is 8.1 to 12 per cent, compared to 2 to 2.2 per cent for incandescent lighting and 8 to 11.45 per cent for the 9-32 watt fluorescent bulb.
As LED lighting technology improves and higher efficiency light bulbs are available, the energy efficiency of LED lighting will increase. The theoretical efficiency limit of a white LED is 260 to 300 lm/W, or approximately 38 to 44% efficiency.
On average, residential LED lights use approximately 75% less electricity than old-fashioned incandescent lighting. LEDs also last 25 times as long, according to study data from the United States Department of Energy.
Learn more about LED lighting’s energy efficiency and cost savings in our Benefits of LED Lighting guide.
How long do LED lights last?
It’s well known that LED light bulbs last for significantly longer than fluorescent or incandescent lights. On average, LED lights last for approximately 25,000 to 50,000 hours of continuous use.
If your home or commercial building depends on artificial lighting for approximately 10 hours per day (for example, during the workday or from the early afternoon until midnight) your LED light bulbs should last for up to 14 years before replacement.
Unlike other lighting technologies, LED light bulbs aren’t damaged by being turned on and off frequently. LEDs also don’t require any time to “warm up” – they provide full lighting from the moment they’re switched on.
Considering fluorescent light bulbs last for, on average, 6,000 to 15,000 hours and incandescent light bulbs rarely provide more than 1,000 hours of light, this makes LED lighting by far the longest-lasting lighting option for homes and businesses.
LED lights also “fail” in a different way from other lights. Unlike incandescent and fluorescent lights, LED light bulbs don’t “burn out”. Instead, they gradually get less effective over time, emitting less light as their lumen value depreciates.
This means that the 25,000 to 50,000 hours figure refers to the amount of time it takes, on average, for an LED light bulb to lose 30% of its lumens, as opposed to a total functional lifespan, as applies to incandescent and fluorescent light bulbs.
Understanding LED colour temperature
LEDs can emit either “cool” or “warm” light. This refers to the temperature of the light emitted by the LED – cool light typically has a bluer look, while warm light is closer to light red or gold.
Interestingly, “cool” light – that is, light with a blue tinge – is actually hotter on the Kelvin Scale than “warm” light. A standard incandescent light bulb emits light that measures around 2,800 Kelvin.
Warm LED lights typically emit light in the range of 2,700 to 3,200K. This level is similar to a conventional incandescent light bulb or halogen light. A cloudy sky is measured at around 6,000 Kelvin, and blue sky light at 10,000 or more Kelvin.
On average, cool LED lighting typically sits within the range of 7,000 to 7,500K on the scale. A white LED light, designed to create light similar to daylight, is between 4,000 and 6,000K.
Light colour temperature is ultimately a personal preference. Most people associate a warmer light with comfort and relaxation, while cool light has been found to help with productive, focused tasks such as reading and learning.
Can you save money using LED lighting?
Although LED light bulbs cost more than fluorescent and incandescent lights, they last longer and use significantly less electricity, making them far cheaper to run in the long term.
Switching from incandescent light bulbs to LED lighting could save you as much as £240 per year as a homeowner, assuming an average level of light use and typical electricity rates.
LED lighting is also more cost effective than energy efficient bulbs, which save just £213 per year and don’t last as long as LED bulbs. By a significant margin, LEDs are the most energy efficient and cost effective way to light your home or building.
In larger commercial and industrial buildings, particularly those that require near constant lighting throughout the day and evening, the savings of LED lighting are even greater.
Learn more about how much you could save by switching to LED lighting in our How Much Does LED Lighting Cost? guide.
Make the switch to LED lighting
Would you like to spend less to light your home or building? LED lighting is a cost effective, long-lasting and environmentally friendly alternative to fluorescent and incandescent lighting.
Switching to LED lighting could save you as much as £240 per year as a homeowner and significantly more as a business. You also benefit from a measurable increase in productivity made possible by the healthy light emitted from LEDs.
We specialise in energy efficient lighting and renewable energy and can help you make the switch to LED lighting. Our team of experts have provided LED lighting equipment, advice and assistance to homeowners and businesses alike.
Would you like to make the switch and lower your electricity bills? Contact us to learn more about the advantages of switching to LED lights and the LED lighting products available for your home or business.
