January 20, 2020
Different Types of Light Bulbs Explained
the choices when buying light bulbs
Lighting can be the difference between a drab room or an inviting one, washed-out or vibrant colors, and a headache or relaxation. An attractive, comfortable home needs good lighting. But lighting has so many variables—brightness, color, temperature, energy efficiency, dimmability—that choosing light bulbs can be confusing.
There are four different types of light bulbs available for residential use: incandescent, halogen, fluorescent, and LED. These varieties have different characteristics including the quality of light emitted, the amount of energy used, and more.
variables in home lighting
Watts measure power usage
Watts (W) are a unit of measure for power that quantify electricity usage. Your electricity provider, for instance, counts kilowatt-hours (kWh, or kilowatts used in an hour) to determine how much to charge you.
When shopping for light bulbs, know the maximum wattage rating of the fixture they will be installed in. The flow of electricity to the bulb creates heat—especially in incandescent light bulbs—and more watts mean more heat. Bulbs with a lower wattage than their fixture ratings are always safe and will be more energy efficient. But if a light bulb draws more watts than its fixture is rated for, overheating can damage wiring and create a fire hazard. Never exceed the rating of the light fixture.
When incandescent light bulbs were the uncontested standard, wattage was used to approximate brightness. More watts meant more light. But with so many options for light bulbs using different amounts of electricity to produce the same amount of light, watts are no longer a useful measure of brightness.
Lumens measure light emissions
Lumens are the best measure of light output. They directly describe how much light is given off by a source. As Energy.gov puts it, “Lumens are to light what gallons are to milk.”
If you want to replace your standard incandescent light bulbs (which, as we will explain, may be a good idea), you need to shop for lumens, not watts. To help you understand lumens in practical terms, Energy.gov gives a rule of thumb for the lumen output of some common incandescent bulb wattages:
- A 100W incandescent bulb emits about 1600 lumens
- A 75W bulb emits about 1100 lumens
- A 60W bulb emits about 800 lumens
- A 40W bulb emits about 450 lumens
Again, different types of light bulbs, such as LEDs may achieve higher lumen figures with fewer watts. Thus, if you want a bulb that is about as bright as a standard 100W incandescent, just look for any model that puts out about 1600 lumens, regardless of the wattage.
When setting up your home, consider how much light each room needs. Interior designers use lumens to get the right amount of light for the right room. Obviously, not every space needs the same amount of light; a hallway doesn’t need to be as bright as an office. Elle Décor offers a simple formula for estimating the number of lumens needed, taking into account the type of room and its size:
- For hallways, square-feet x 7.5
- For bedrooms, square-feet x 15
- For bathrooms, square-feet x 75
- For kitchens and dining rooms, square-feet x 35
Your needs may vary, however. How bright you want a bathroom, for instance, may depend on the color of the tile and how often you clean it.
Different colors for different needs
Don’t forget about color when lighting up your home. Different-colored lights are appropriate for different settings. Plain (in other words, not specially colored) light bulbs emit light with color ranging from yellow to blue.
When you shop for lightbulbs, you’ll find that light color is often measured in something called the Kelvin [K] Color Temperature Scale. The physics behind the scale are interesting but not helpful for buying lightbulbs. What you need to know about the color temperature is that 2700K is very yellow and 6500K is very blue.
Different color temperatures have different uses and provide a different ambiance. In general, yellow light feels warmer and more relaxed while blue light feels cooler and provides more clarity and alertness. Consider the following guidelines when purchasing bulbs:
- Between 2000K and 3000K is good for rooms like bedrooms, living rooms, and dining rooms. 2700K (often called “warm white”) is a common color.
- Between 3500K and 4000K is good for locations where you need more attention to detail—like kitchens, bathrooms, and offices. Colors in this range are sometimes called “cool white” or “neutral white.”
- Light around 4500K is good for work areas where clarity and detail are more important than ambiance, like reading lamps and vanities for makeup application.
- 5000K and higher is very intense and is appropriate for places like garages.
types of lightbulbs
After you figure out the wattage of your fixtures, add up how many lumens you need, and decide on a color, you have to actually pick light bulbs.
There are several types, each with specific features and uses. But fear not! Understanding the differences is easy. For residential settings, there are four main types of light bulb:
- Incandescent bulbs
- Halogen bulbs, a subcategory of incandescent bulbs
- Fluorescent bulbs
- LED bulbs
Incandescent bulbs—the original
The mainstay of the lighting world for about a century, the incandescent bulb is what Thomas Edison received credit for inventing. And these devices are fairly simple, technically speaking. The flow of electricity heats a metal filament (typically tungsten) until it glows. To prevent oxidation and prolong its life, the filament is housed in a glass bulb filled with an inert gas (commonly argon and nitrogen, but also sometimes krypton and xenon).
Incandescent light bulbs have several advantages. They give off a warm light color, they are cheap, and they are dimmable. On the other hand, incandescent bulbs are hot and energy-inefficient. For this reason, they aren’t as widely available as they used to be.
In 2007, the Energy Independence and Security Act mandated 25% greater efficiency for light bulbs that used between 40 and 100W. Contrary to popular belief, this law did not ban incandescent bulbs; it merely requires greater efficiency. Exceptions exist for some special-use bulbs but, in general, the selection of incandescent bulbs was reduced by the law.
Halogen bulbs—improved incandescent lights
Halogen bulbs are basically improved incandescent bulbs. They have the same tungsten filament found in incandescent bulbs but it lasts longer. You may know halogen bulbs as the “bulb-within-a-bulb” lights. The innermost bulb of a halogen light houses the filament as well as halogen gas (iodine, bromine, or both) which prolongs the life of the filament.
Halogen bulbs produce light of a similar color and quality to normal incandescent bulbs, are low-cost, dimmable, and long-lasting. However, they share the relative energy-inefficiency of traditional incandescent bulbs.
Fluorescent light bulbs
Fluorescent light bulbs are common in offices and parking garages and they are known for intense, hard-on-the-eyes light. They don’t have filaments like incandescent light bulbs. Instead, fluorescent bulbs consist of a glass tube that’s coated on the inside with phosphor powder and filled with inert gas and small amounts of mercury. The flow of electricity through the tube ionizes the mercury, which emits ultraviolet (UV) light. The phosphor powder absorbs the UV light and in turn, emits visible white light.
The advantages of fluorescent lights include energy-efficiency and producing light on the white end of the color temperature spectrum—which is desirable in some environments. Fluorescent lamps are also long-lasting, having a lifespan of about 10,000 hours compared to the 1,000 hours of incandescent bulbs. They are also available in many shapes including long tubes, U-shapes, and compact models that fit household fixtures.
Fluorescent light bulbs have several disadvantages, however. The light they emit can be very harsh. They may not be dimmable. They also often take time to “warm up” after turning on. Finally, safe disposal is difficult because of the mercury, which is harmful to humans and should not be released into the environment.
LEDs are long-lasting and energy-efficient
LED stands for light-emitting diode—and LEDs have claimed the crown as the next big thing in lighting. The way they work is more complex than the other light bulbs mentioned here. But essentially, electricity flows through a semiconductor and produces light when it “jumps” across a nonconductive region.
LEDs have numerous advantages:
- They don’t require a filament to be heated, so they are very energy-efficient. LEDs produce the same lumens as an incandescent bulb for a fraction of the watts.
- LEDs don’t require mercury, so they are environmentally friendly.
- Many LEDs are dimmable.
- They are very long-lasting, with average life-spans of 25,000 hours—25 times the average life of an incandescent bulb and about 10x the life of fluorescents.
LEDs are excellent light bulbs, but they do have some drawbacks. The first is the upfront price. While they are becoming more economical, LEDs may be more expensive per lumen than lower-tech alternatives. This is of course offset by the fact that they last a lot longer.
Another caveat is the “shape” of LED light. Incandescent bulbs project light roughly spherically, in all directions, whereas LEDs emit light more directionally. This can be mitigated with lenses, but you should take it into account.
light right—and get it smart!
Picking the best light bulb isn’t that hard. If you simply pay attention to power usage, color, and brightness and understand the different kinds of light bulbs, you can get the right illumination for any room in your house.
There is way more to lighting than color and wattage, however. And perhaps the biggest innovation in the past decade or so is the widespread use of smart lighting.
Smart lighting is part of home automation, a technology that connects everyday objects like locks, cameras, refrigerators, and lights to the Internet. Smart homes offer unparalleled convenience and security, and making your lights “smart” achieves both of these objectives.
Smart lights work on two simple principles—remote control and automation. A smart light can be commanded to turn on, off, dim, or change color through a wireless signal sent from a control center like the Frontpoint Hub. The “brains” of a smart home, it enables you to command your lights and various other appliances with a smartphone, computer, or another device from anywhere.
You can turn lights on and off with the swipe of a screen or program different lighting “scenes” to turn on according to vocal cues, the press of a button, or a schedule. To learn more, check out our article explaining exactly how smart lighting works and what it can do.
Frontpoint offers two smart lighting solutions. The first is the smart Light Bulb, an energy-efficient dimmable LED that fits in standard light fixtures. The second is the Wireless Light Control, an outlet adapter that lets you integrate standard lamps and other appliances into your smart home—as long as it plugs into a standard outlet, any device can become “smart.”
Choose your lights wisely. And for added benefit, control them at any time, from anywhere.
Be sure to check out other blog posts, like this one on how home security systems work when the power goes out or this piece that explains how Z-Wave hubs work.
Frontpoint keeps homes safe whether families are there or not. We've been revolutionizing the home security industry for over a decade. And we're just getting started. To shop DIY home security systems, check out our Security Packages. If you have questions or would like to discuss a quote, contact us at 1-877-602-5276.