Intro to LED Lighting

We continually screen and adopt the most current and efficient “green” lighting products and technologies. At the top of our green list is LED technology, an ideal choice for many residential and commercial lighting applications. Because this is an emerging technology, there is a lot of information—and misinformation—out there.

Our hope is that this guide will bust some of the LED myths, highlight the benefits of LEDs, and provide helpful insights when shopping for your LED bulbs and fixtures.

LED Basics

What is an LED?

An LED (‘Light-Emitting Diode’) is a small semiconductor device that produces light when electrical current flows through it. LED fixtures and LED bulbs are often composed of many individual LEDs.

What are the benefits of LED technology?

LED technology offers numerous benefits, including:

  • Energy Efficiency. LEDs are far more energy efficient than incandescent and halogen light sources, saving electricity and reducing operating costs. Consider that a 60W incandescent bulb is typically replaced by an 8W or 9W LED bulb!
  • Long Lifespan. LEDs last much longer than incandescent and halogen light bulbs. The average lifetime of an LED can be upwards of 25,000 operating hours. Compare that to the 1,000-2,000-hour average lifetime of many incandescent and halogen bulbs.
  • Design Versatility. LEDs offer much more versatility in design, thanks to their small size and color temperature options.
  • Green Technology. Unlike fluorescent and compact fluorescent light bulbs, LED bulbs are mercury free, making them today’s energy-efficient bulb of choice. And with the infrequency of replacement compared to their incandescent counterparts, LEDs create significantly less waste.

Where should I use LED technology?

LEDs are growing in popularity in almost every room of the home. The long lifetime of an LED means they require very little maintenance compared to incandescent bulbs, so more and more people are choosing LEDs for hard-to-reach places, such as cathedral ceilings. Other great applications for LEDs include closets, under cabinets, step lights, bathroom lights, and other high-use areas that could benefit from energy-efficient lighting.

Landscape lighting in particular is a wonderful application for LED technology. LEDs can be used to highlight architectural elements, trees and shrubs, footpaths, water features, and stone walls. LED flood lights offer long life, provide security, and are maintenance free, making them an excellent choice for that application.

Brightness & Lumens

While many of us are used to thinking in terms of watts when we think about how bright a light bulb or light fixture is, a better measure to use with LED bulbs and fixtures is lumens. Watts is a measure of energy consumption, and different LED bulbs and fixtures don’t have a predictable correlation between wattage and brightness – some LEDs are more efficient than others.

Lumens, however, is truly a measurement of brightness, and so it’s a better number to look at when comparing the brightness of different light sources.

To replace your incandescent light bulbs or light fixtures with LEDs, choose an LED that has a similar lumen output to the incandescent source you’re replacing. Here are some useful reference points:

  • A 40W incandescent light bulb is about 450 lumens
  • A 60W incandescent light bulb is about 800 lumens
  • A 75W incandescent light bulb is about 1100 lumens
  • A 100W incandescent light bulb is about 1600 lumens
G25 Curly Filament LED Bulb

Color Rendering & CRI

CRI stands for ‘Color Rendering Index’, and grades how true-to-life an object will look under a light source. Have you ever been in a room with older fluorescent lighting and felt that everything looks greenish or sickly? Older fluorescent light sources had very low CRI, which tends to make objects look dull, flat, or just ‘not-right’. High CRI sources, on the other hand, make colors look their most natural and vibrant.

CRI is measured on a scale out of 100, with 100 being perfect color rendering. An incandescent bulb has a CRI of 100, as does sunlight. Most LED bulbs and fixtures on the market today have a CRI of at least 80, and some have excellent CRIs greater than 90 or 95. High CRI light sources are especially important in applications where accurate color is vital, like kitchens and bathrooms, or for lighting artwork.

In the photos below, notice how the typical LED with lower CRI makes the plate of peppers seem dull compared to the vibrant colors brought out by the high CRI light source.

Soraa Peppers Low CRI

Low CRI Light Source

Soraa Peppers High CRI

High CRI Light Source

Color Temperature

When we talk about color temperature in regards to LEDs, we’re discussing the color of the white light an LED provides. For example: Is it amber in color? Is it a bright white? Does it have a blue tint?

Color temperature is measured in Kelvin (K). The lower the color temperature of a light source is, the warmer (redder) the light will be. The higher the color temperature of a light source is, the cooler (bluer) the light will be. Think of the color shift that a piece of metal goes through as it is heated. When you first begin to heat it, the metal has a warm red glow. As the temperature increases, it becomes white-hot, and then finally it becomes a blue color when it is hottest of all.

Candlelight naturally is about 1800K, incandescent bulbs are about 2700K, halogen bulbs are about 3000K, and daylight at noon on a summer’s day is about 6500K. LEDs are available in many color temperatures, and when you purchase an LED bulb or fixture, it’s important to pay attention to the color temperature to make sure you know what color light it will provide. Note, however, that there is variation within color temperatures, and two bulbs or fixtures may look a little different even if they are the same color temperature on paper.

In the image above, Ketra’s tunable LED lamp demonstrates a variety of color temperatures

Which color temperature is right for you and your home? Color preferences are very personal, and so this is a difficult question to answer. Most people tend to prefer LEDs in the 2700K-3000K range because we are used to the color of incandescent and halogen bulbs. Being a bit lower on the Kelvin scale, 2700K has a warm cast to it. It tends to flatter skin tones and warmer color palettes and can make a room feel cozy and comfortable. 3000K, on the other hand, comes across as a more neutral white light. It is more flattering to cooler color palettes, can help a space feel brighter, and helps to keep white surfaces looking white without giving them a yellow cast.

You could, of course, choose LEDs that are higher in color temperature than 3000K – retail and commercial spaces, for example, often utilize color temperatures of 3500K+ for crisp, energetic, neutral white lighting. The best way to know what color temperature is right for you is to see the options in person.

Please note: terms like ‘warm white’ or ‘soft white’ can be used differently by different manufacturers, and they can refer to different color temperatures. For example, one manufacturer may use ‘warm white’ to refer to 2700K, and another may use it to refer to 3000K. The best way to understand the color temperature of an LED is to look at the color temperature in Kelvin.

RGB & Tunable White

One of the possibilities that LED technology offers is adding colorful and color-changing light to your home. You may have seen or heard of RGB lighting. RGB fixtures or systems include red, green, and blue LEDs that can be controlled in different combinations. By combining these colors together in various degrees and intensities, countless colors can be created. An RGBW fixture or system takes this a step farther, adding white LEDs to the mix. This allows you to easily create pastel colors and gives you the choice of just white light if you’re feeling a little less colorful.

Ketra Lighting Tunable Color. Photo Credit: Magda Biernat

Related to color-changing LEDs, you may have also heard of ‘tunable white’ (also known as ‘dynamic white’, ‘intelligent white’, and so on). Tunable white fixtures and systems are similar to RGB or RGBW systems because you can control the color of the light. However, they allow you to change the color temperature of the lights (warmer or cooler) rather than the color (purple, blue…).

For instance, if the lights in your kitchen are tunable white, you could begin the day with a warm glow at 2400K. You could then brighten things up midday to 4000K as you clean, bring the color temperature lower but still task-light friendly to 3000K when cooking dinner, and return to a warm 2400K when you’re having your after-dinner drinks at the kitchen island. With tunable white systems, you can dial in exactly the color temperature that suits the atmosphere you’d like to create.

Over the past few years, RGB, RGBW, and tunable white lighting has become increasingly popular in homes. The possibilities are endless, and this is one of the most exciting LED technologies as it becomes even more sophisticated and accessible.

Dimming

LEDs are more particular than incandescent sources when it comes to dimming. Not all dimmers are compatible with all LED bulbs and fixtures – even dimmers that are marketed as ‘LED dimmers’! We always recommend looking at the specifications of your LED bulb or fixture to determine the dimmer that will work best. Bulb and fixture manufacturers will often publish lists of dimmer models they have tested and approved for use with their products.

If an LED bulb or fixture and dimmer are not compatible, you may experience flickering or buzzing, the LED may not dim as low as you would like, or the LED may not turn off completely when you switch the dimmer off. In some cases, you may also shorten the lifetime of the LED bulb or fixture, causing it to fail prematurely. We are always happy to help with dimmer recommendations, so please feel free to reach out to us if you have questions.

Another difference between dimming LED and incandescent sources has to do with color shift. As incandescent light sources dim, the light warms in color temperature. Think of how dimming a chandelier with incandescent bulbs gives you a candlelit glow in your dining room. LEDs do not naturally color-shift when they are dimmed but dim in brightness only. If you would like a dimming experience similar to incandescent, look for LED bulbs and fixtures that are ‘warm-dim’ or ‘dim-to-warm’. These are designed to shift in color as they are dimmed, mimicking the dimming curve of an incandescent bulb. You can now find LED bulbs as well as integrated LED fixtures that have this feature.

Things to Consider

Integrated LED vs. Retrofitting with LED Bulbs

There’s no doubt that switching to LED will help with energy efficiency, but do you want to replace the light bulbs in your fixture only or change out the fixture entirely to an integrated LED? There are some things to keep in mind with each approach.

Retrofitting existing fixtures with LED bulbs is often quick and easy, requiring the least financial investment up front. However, LED bulbs in general don’t dim as well as integrated fixtures do, and so you may not get the dimming performance that you’re looking for. Bulbs also change pretty often, and you might not be able to find a matching bulb if one fails early.

Integrated (‘dedicated’) LED fixtures don’t have light bulbs in them at all but have an LED light engine designed specifically for that fixture. This allows for greater design flexibility, making possible: a 2” LED recessed light that’s as bright as a 5” incandescent downlight, a vanity light with a sleek, slim profile, or a discreet but bright LED strip that can be tucked into a ceiling cove. Integrated LED fixtures also tend to have better dimming performance when used with a compatible dimmer, dimming lower and more smoothly than a bulb might.

LED Buying Checklist

As you look at different LED options, keep the following checklist in mind:

  • Pay attention to the color temperature in Kelvin (K) and learn what color temperature you like best.
  • Look at the CRI and choose high CRI LED bulbs or fixtures in areas where accurate color is important to you.
  • If the LED bulb or fixture will be on a dimmer, check the LED specifications and use a dimmer that is compatible.
  • Many LED bulbs and fixtures have warranties. Review the warranty information and consider how long the warranty is and what it covers. Since LEDs are designed to last a long time, it’s important to choose bulbs and fixtures from reputable manufacturers that are well established in the industry and will be around if an issue arises later on.
  • Confirm that the fixture is UL or ETL listed. UL stands for Underwriters Laboratories, Inc. and ETL is a mark for Intertek Testing Services. Essentially, these certifications assure you that the fixture and bulb have gone through rigorous testing. Consider it a seal of approval. Note: most electricians will not install non-listed fixtures.

Any Questions?

Need assistance finding the right LED fixture for your specific application? We’d be happy to help! Meet with a lighting expert to discuss your project.

Lighting Consultation