Better Bulbs: Brighter Future
A Look at Inefficient Lighting
The invention of the light bulb profoundly changed human existence, and yet today, the ubiquitous incandescent light bulb is practically synonomous with our throw-away culture. It's hard to think of a product that is more affordable, but what is it really costing us?
Incandescent lighting technology has remained largely unchanged since it's invention over a 100 years ago. Incredibly, only 10% of the electricity consumed by incandescent light bulbs is converted to light. The remaining 90% of the energy used is emitted as heat from the bulb. With the rising need for efficient lighting, our next best option is a switch to compact fluorescent lamps (CFLs).
Why Does Lighting Matter?
In order to reduce our greenhouse gas emissions, we need to look at any area where we use fossil fuels: the major uses are transportation and electricity. As fossil fuels are burned to supply electricity to homes and workplaces, power plants discharge many pollutants into the atmosphere, including carbon dioxide (CO2), a greenhouse gas that is a primary culprit in global climate change. For every kilowatt-hour of electricity used, power plants release 1.5 to 2 pounds of CO2 into the environment.*
Wasting electricity is also expensive: The average household spends 10-15% of its annual electricity bill on lighting, according to the Environmental Protection Agency.
Let There Be [Fluourescent] Light
Replacing just one incandescent bulb with a CFL will reduce CO2 emissions from power plants by over 700 pounds over the life of the bulb. The EPA estimates that if one room in every U.S. home were switched to CFLs, we'd reduce CO2 emissions by over one trillion pounds.
CFLs Save Money
The cost- and energy-saving benefits of CFLs are clear. It's true that CFLs cost significantly more per bulb; however, they can last up to 13 times longer than incandescents, and use 75% less energy. Ultimately, CFLs will save you a significant amount of money. For example, these two bulbs emit a comparable amount of light, but check out the cost savings:
|
CFL
(20 Watt) |
Incandescent
(75 Watt) |
Bulb Costs
(10,000 hours)
|
$17 (one bulb) |
$9.75
(13 bulbs @ $.75 ea.) |
Energy Use
(10,000 hours)
|
200 kWh |
750 kWh |
Energy Costs
(10,000 hours)
|
$16.58* |
62.18* |
Total Cost |
$33.58 |
$71.93 |
| |
|
|
*Calculated at a rate of $.0829 per kWh |
Choose the Right Bulb
CFLs are available in a variety of color temperatures and brightness levels. In general, look for bulbs labeled with a Color Rendering Index (CRI) of 80 or higher for the most pleasing color results. The key to getting the right light is to accurately assess your lighting needs before you choose your bulb. In a home, two types of lighting are usually needed: ambient lighting and task lighting. Ambient lighting is background light that does not generally need to be as bright as task lighting, which requires focused light to illuminate spaces for reading, cooking, or other tasks. Keep the specific lighting need in mind when choosing among the many available CFL bulbs.
A bulb's energy use is denoted in watts, while its light output is measured is lumens. In order to choose the right CFL replacement for an incandescent bulb, look for a model with a comparable lumen output.
| Incandescent Bulb Wattage |
Light Output (Lumens) |
CFL Bulb Wattage |
40 Watt |
= 450 Lumens |
= 9-11 Watt |
60 Watt |
= 800 Lumens |
= 13-15 Watt |
75 Watt |
= 1,100 Lumens |
18-20 Watt |
100 Watt |
= 1,600 Lumens |
= 23-25 Watt |
| |
|
|
In addition to reading the information found on the bulb's packaging, look for the EPA's EnergyStar logo as an indicator of a product's efficiency. Over a thousand models - most of which are easily found in home improvement and hardware stores - qualify for the EnergyStar label. The Energy Star web site maintains an updated list of participating manufacturers and models. Some of these manufacturers also produce non-EnergyStar light bulbs, so don't just look for the company name; make sure the specific bulb model you buy carries the EnergyStar label.
CFL design has improved a great deal in the past few years. There are now even models that work with a dimmer switch. CFLs fit into most existing fixtures, but if you have an older fixture that does not accommodate a CFL bulb, think about replacing the fixture - it will save even more energy and money in the long run.
The Mercury Issue
All fluorescent bulbs contain a small amount of mercury; however, the use of CFLs still results in a net reduction of mercury compared to incandescent bulbs. This is because of the lower energy use: using less electricity equals lower mercury emissions from coal-fired power plants. Lower-mercury bulbs also are becoming more available. For example, Philips has several low mercury alternatives. CFLs also require careful disposal to avoid mercury contamination in landfills.
Safe Disposal of CFLs
The good news is that CFLs last so long that you will rarely need to dispose of them. When the time comes, the best way to dispose of used CFLs and other fluorescent light bulbs is to take them to the City of Austin's Household Hazardous Waste Facility at 2514 Business Center Drive [map]. The facility is open from noon to 7 p.m. on Tuesdays and Wednesdays. Better still, encourage retailers who sell CFLs to recycle them. The new Ikea store in Round Rock will take used CFLs (whether or not they were purchased from Ikea) at it's Customer Service Center.
The New Frontier
Even though CFLs are a good alternative to incandescents, early adopters are already seeing the advantages of light-emitting-diode (LED) bulbs and fiber optic lighting. LEDs have more focused light output and more color variety. They also have a longer life and ever better energy efficiency: current LED bulbs last up to 60,000 hours and can use as little as two watts of energy. The down side is that it is still expensive and most commonly available for residential use only in accent lamps and chandeliers. Fiber optic lighting, already in use in some grocery stores, uses 80 percent less energy than halogen or incandescent bulbs and generates no heat (a good choice for grocery-store freezers). One major manufacturer, Fiberstars, has plans to introduce residential fiber optic products within the next year or so.
Optimize Your Lighting
 |
Maximize your use of natural daylight. |
|
Reduce ambient light levels; use concentrated task lighting. If you are reading, for example, turn off ceiling lights and rely on a small, focused lamp instead. |
|
Make sure you periodically wipe light fixture reflectors and diffusers, according their manufacturers' directions, to ensure that you're getting the maximum amount of light from the bulb. |
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Pick lampshades and diffusers that let the most light through while still filtering glare. |
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Choose light-colored paints and flooring; lighter colors better reflect light (including natural daylight) and reduce the need for electric lighting. |
*Source:
Resources
More On LED Lighting
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