LED Lighting Guide
Last Updated: Apr 9, 2025Over two-thirds of all Americans have purchased LED lights for their homes. The EPA believes that LEDs will become the most common household lighting source by this year if current trends persist. The energy efficiency benefits of LED lights are well known and documented by green building professionals and users. However, we seldom hear or consider some of the potential disadvantages of this new light bulb revolution. So, today, we will discuss the pros and cons of LED bulbs.
Table of Contents
- What is LED Lighting?
- How Does an LED Light Work?
- How Do I Convert Watts To Lumens?
- What Color Temperature Are Led Lights?
- What Is the Equivalent Wattage for Led Bulbs?
- How Long Do Led Light Bulbs Last?
- Do LED Bulbs Save Energy?
- What Causes LED Lights To Flicker?
- How Much Can Be Save By Switching to LED Lights?
- Do LED Bulbs Contain Hazardous Materials?
- How Could LED Lighting Impact Health?
- Is Bluelight Harmful?
- How Can You Make The Best Choices with LEDs?
- Bottom Line
What is LED Lighting?
LED, short for light-emitting diode, is one of the most rapidly developing lighting technologies. In its simplest form, LEDs produce visible like when an electric current passes through its semiconductor. This form of light production is quite different from incandescent or CFL, which use vacuums or gas, respectively. LEDs offer better light quality and overall lifetime compared to incandescent and CFL lighting alternatives.
How Does an LED Light Work?
LEDs are a semiconductor light source that generates spectrum light by passing a unidirectional current through it. How does this happen? The semiconductor has two layers, one negative layer (cathode) with free-floating electrons and one positive layer (anode) with openings for electrons often called holes. When an electric current passes through the negative layer into the positive layer, it releases photons through those holes, creating light.
How Do I Convert Watts To Lumens?
When buying LED lights, look for lumens, not watts. Watts = lumens / (lumens per watt). To take out a lot of the guesswork, here is a simple chart you can follow.
- 100W incandescent = 1600 lumen LED
- 75W incandescent = 1100 lumen LED
- 60W incandescent = 800 lumen LED
- 40W incandescent = 450 lumen LED
What Color Temperature Are Led Lights?
LED color temperature is measured in Kelvin (K) and commonly described as warm, cool, and daylight.
- Warm = 2200K to 3000K
- Cool = 3500K to 4100K
- Daylight = 5000K to 6500K
For comparison and replacement of older lighting sources, candle, CFL, incandescent, and halogen are 1900k, 2700k, 2800k, and 3000k, respectively.
What Is the Equivalent Wattage for Led Bulbs?
If you are looking to make a direct replacement from your existing incandescent lights to LED, you can follow these suggestions:
- Incandescent 40 W = LED 8 W
- Incandescent 60 W = LED 13 W
- Incandescent 75 W = LED 17 W
- Incandescent 100 W = LED 20 W
Do LED Bulbs Save Energy?
LED lights are designed to use 75% to 80% less energy than incandescent lights and roughly 18% less than CFL lights.
What Causes LED Lights To Flicker?
LED lights can flicker due to voltage fluctuations in your home's wiring, or it could signal loose wiring in your lighting fixture. In both cases, call your electrician to take a look.
How Could LED Lighting Impact Health?
When LED lighting came on the scene, most bulbs produced bright, cool, bluelight. Now, there is a wide range of color warmth options (not to mention fun colors) to choose from.
Is Bluelight Harmful?
Long term exposure to LED lights in the daylight or cool white color range (4,600-6,500 Kelvins) might also disrupt sleep patterns. Bluelight has a short-wavelength and is considered to be an "aggressive" sort of light that keeps us alert and awake during the day. However, bluelight needs to be balanced during night time hours by other colors of light—particularly red light, which is on the opposite side of the spectrum.
Exposure to large amounts of bluelight during night time can negatively affect our circadian rhythms that govern our sleep habits. A research project by Harvard Medical School found that bluelight can actively suppress melatonin secretion and subsequently shift our circadian rhythms by twice as much as exposure to other types of light on the spectrum. So, choose warmer color LEDs for bedrooms and leisure areas of the home (2,000 to 3,000 Kelvin range).
Another crucial area to consider is the amount of bluelight we are exposed to from other sources like TV and computer screens. There is evidence that the bluelight could be leading to long-term eye problems such as prematurely aging of the eyes, digital eye strain, and even retina damage.
Tobias Roberts
Tobias runs an agroecology farm and a natural building collective in the mountains of El Salvador. He specializes in earthen construction methods and uses permaculture design methods to integrate structures into the sustainability of the landscape.