If you’re not familiar with LED lights, you’ll want to find out about them, because pretty soon you won’t have much choice: regular incandescent light bulbs will no longer be available at most stores.
What’s wrong with regular light bulbs? For starters, they waste too much energy, cost too much to operate, and are not as efficient as the new LEDs.
LED light bulbs can save energy, help protect the environment, reduce maintenance costs, and make everything look more attractive than traditional lighting. And they last longer—much longer than traditional lights.
Can LED lighting really save energy and money? Take a look at the statistics. The U.S. Department of Energy estimates that widespread adoption of LED lighting by 2025 will:
• reduce electricity demands from lighting by 62 percent,
• eliminate 258 million metric tons of carbon emissions,
• reduce landfill waste,
• prevent building 133 new power plants,
• and save the U.S. over $280 billion.
If we accept the challenge to replace our incandescent and CFL light bulbs with LED bulbs, we could save $25 to $35 million over 25 years in Jefferson County alone!
What is an LED?
LED stands for light emitting diode. It creates light by running a current through a solid-state circuit board. It requires very little energy to operate and produces very intense light that flows in a single direction. When you put several LEDs together, along with a power supply, a heat sink, and an optical lens, you get a powerful lamp that lasts around 50,000 hours.
A typical LED lasts 30 to 50 times longer than a regular light bulb and 5 to 10 times longer than a compact fluorescent (CFL). How long is that? Assuming an LED bulb was turned on 4 hours per day it would last 34.2 years. If used 2 hours per day, it would last 68.5 years. Imagine not having to change light bulbs in your lifetime!
What Makes An LED Efficient
Okay, please forgive me, as this will get a bit technical. Efficiency in lighting is measured in lumens per watt. That means, if you make more light using less energy, it’s more efficient.
The heat output also affects efficiency and longevity. LEDs lose 20 percent of their energy in heat and are affected by ambient temperatures, especially in hot climates. CFLs lose 40 percent, and incandescent bulbs lose a whopping 90 to 95 percent of their energy in heat.
Let’s talk about light output—delivered lumens. The ability of a light bulb to illumine an object depends on upon how many lumens actually leave the fixture. Therefore, when comparing lumen output, you need to compare the amount of lumens that are delivered.
Regular light bulbs and CFLs, for example, generate plenty of lumens, but because they are omni-directional they emit light in all directions (360 degrees). Only about 50 percent illumines the objects below. LEDs, on the other hand, create directed light and use 91 percent in the downward direction. This makes more efficient use of the lumens it creates.
What about light quality? The higher the CRI (color rendering index) number, the closer it is to real sunlight, which is rated at 100. The CRI ratings of LEDs vary from 70 to 93, CFLs are about 60 to 80 and incandescents are rated at 100.
What’s the Real Cost?
Okay, let’s talk about money. A 65-watt incandescent bulb costs about $1. A comparable CFL costs an average of $5, and an LED costs an average of $35. Don’t be swayed by the initial costs! There are significant replacement costs with CFLs and incandescents.
LEDs save 80 percent over incandescent, 40 percent over CFLs, and 20 to 30 percent over fluorescent tubes. The payback on LED bulbs is 4 to 5 times the initial cost! Or, put another way, each LED purchased will save you about $316 over the lifetime of the lamp. But there’s more.
Environmental and Health Benefits
In terms of global warming and carbon emissions, it’s clear that the use of LED bulbs and fixtures will have an enormous impact on the power grid. This reduces overall energy demand and the need to build more power plants.
Both LEDs and incandescent bulbs can be recycled, but CFLs cannot due to minor amounts of mercury. With LEDs there are fewer to recycle, less waste, and no mercury. LEDs operate at very cool temperatures (70 degrees F.) compared with CFLs or incandescents. This means lower air conditioning costs and less wear on AC units.
LEDs contain allmost no EMFs (electromagnetic frequencies), compared with medium to high concentration in CFLs. CFLs also tend to flicker, as do fluorescent tubes which bother many people.
Only a few LEDs are certified by Energy Star. Make sure you check, as rebates on LEDs from most utility companies require at least Energy Star certification.
Joel Hirshberg is the founder of Green Building Supply in Fairfield, Iowa.
For more information, check out these useful links:
US Dept of Energy – Energy Efficiency & Renewable Energy
LED University – working to accelerate the adoption of LEDs
Visit the index for more articles on green living.