the structure of typical LED bulb

All You Need to Know about LED Bulbs

As of January 1, 2014, 40- and 60-watt incandescent light bulbs became obsolete in the U.S. Though the U.S. Congress refrained from declaring them a thing of the past altogether, it was already obvious that LED bulbs were taking over. Consumers and manufacturers alike are aware of this and doing everything in their power to get the end-user more bang for their lighting buck.

LEDs come with a lot of advantages – perhaps, most notably, their impressive lifespan of over 20 years. This also makes them economically efficient: in spite of the fact that they initially came with high price tags, recent technological advances have driven those prices down.

LED bulbs are still about five times more expensive than incandescent bulbs, but cost alone shouldn’t deter you from the environmentally sound decision of switching. Variety, on the other hand, might find you a bit overwhelmed with choices.

This why today’s article is a primer on the actual definition of LED light bulbs. We explain their main feature, how they work, what to consider when buying them, and how to navigate the wide range of options in terms of LEDs for different purposes. Read on to get educated on LED bulbs!

What are LED light bulbs?

The acronym ‘LED’ stands for ‘light-emitting diode’. An LED lamp or LED bulb is a semi-conductor that produces visible light when electrical current runs through it.

the structure of typical LED bulbs

Image source: Mentor

The difference between an LED bulb and a compact or fluorescent light source is that LEDs are directional. In other words, while the aforementioned types of bulbs diffuse light and heat in all directions, LED bulbs emit them in a single direction.

The directional quality of the light they produce makes LEDs highly efficient and useful in several settings and applications. At the same time, replicating a typical A-shaped lightbulb with LED lighting requires complex means of production and sophisticated engineering.

Aside from this feature, LEDs are also:

  • SSL (Solid State Lighting) devices;
  • OLEDs (Organic Light-Emitting Diodes);
  • LEPs (light-emitting polymers).

The lifespan of an LED bulb is also calculated differently from that of a regular CFL or incandescent light bulb. That’s because, unlike the other major types of bulbs, LEDs don’t actually ‘burn’ out. Rather, they go on to emit a proportionately lower amount of lumens as time goes by. In other words, the amount and color of light they produce can radically alter in time.

With most conventional light bulbs, their ‘lifespan’ is taken to mean the time it takes for 50% of them to burn out. With LED lamps, it’s calculated according to the estimated span of time after which they end up giving out 30% less light than they did in the beginning.

Thermal management, i.e. the way in which heat is driven away from LED bulbs, plays a central part in how well a particular LED design works. That’s because, unlike halogen and incandescent bulbs, LEDs don’t emanate heat—the heat they generate must be drawn away from them. This is where heat sinks come in, to keep LED bulbs from becoming overheated and eventually burning out.

An LED bulb with a poorly designed heat sink is forced to work at inappropriately high temperatures. In time, it will produce poorer light, experience a reduction in lifespan, and ultimately be less useful. While heat sinks may come in all shapes, sizes, and designs, it’s important that they do their job well so that the bulbs last for as long as the manufacturer intended them to.

Why are LED lightbulbs so popular?

From a consumer point of view, the main difference between LED light bulbs and CFL or incandescent bulbs is that the former can far outlast the latter. They’re also more adaptable and sturdier. Before we dive into all this, let’s take a look at how they work, the kind of light they produce, and loads more details.

Light Emitting Diodes are very efficient sources of light. They are powered by electricity, which runs through the semiconductor part of the fixture and, in turn, lights up a very small source. That source is what we call an LED per se. LEDs also come with the great advantage of not overheating – that’s because all the heat they emit is absorbed into a heat sink.

In a nutshell, here’s how incandescent bulbs, CFL bulbs, and LEDs differ from one another:

  • LEDs generate heat and light through the passing of electricity through a semiconductor. That light is unidirectional.
  • CFL bulbs generate ultraviolet, or UV, light and heat. The electricity passes from one end to the other of a gas-filled tube. The UV is created through the passage of the current from an electrode to the other. UV light can be seen when it hits the phosphor covering within the tube.
  • Incandescent lightbulbs generate light by heating metal filaments to the point where they’re white hot, or incandescent, as their name also suggests. Since heat plays a major role in this equation, it should come as no surprise that this type of light bulb releases 90 per cent of the energy it contains as thermal energy.

Types of LED bulbs

LED bulbs and fixtures can take on a wide range of shapes and forms. It’s very possible that the first time you saw such a light, you weren’t even aware you were looking at it, as it could well have been incorporated into a set of Christmas lights, a display screen, or a power button.

Since LEDs are very small, they lend themselves to a wide range of design opportunities. While some might look like actual light bulbs, not all of them do; yet, those which don’t might very well be more efficient lighting sources. It is often the case that an LED light that doesn’t look like a traditional light bulb actually better matches the latter’s capacity. Some LED lamps out there might even have an in-built LED—a permanent source of light.

A common misconception about LED bulbs is that their color is white. That’s because most of the LED lamps we use to power our homes and offices are white. However, in reality, all-white LEDs don’t even exist. The white light they emit is obtained by mixing various colors of LEDs, or by covering their surface with phosphor. Phosphorus is a yellow substance you sometimes see covering LED bulbs.

The best LED light bulbs

Before we delve into specific brands, features of LED bulbs, and designs, it’s worth mentioning that such fixtures that are ENERGY STAR compliant will typically provide the best experience. When you buy an Energy Star certified LED bulb, you can expect the following:

  • 6 color requirements, which guarantee you’re getting the best quality, both when you buy and in time;
  • light output requirements:
    • to ensure a minimum standard of lighting;
    • to ensure the directional feature and make sure you’re getting light exactly where you need it;
    • to ensure that you’re covering your lighting needs in terms of output and correctly replacing traditional lightbulbs with an equivalent corresponding LED bulb.
  • compliance standards:
    • the Energy Star certificate is awarded after checking that a specific product corresponds with over 20 industry procedures and standards;
    • compliant bulbs are tested to make sure their lifespan actually matches the manufacturer’s claims;
    • compliance tests are carried out in environments that try to simulate standard home usage.

So, now that you know all this, you might feel totally ready to head on down to your nearest hardware store and pick up some LED bulbs. But the truth is buying LEDs is completely different from buying incandescents. So before you spend your hard-earned money, check this out:

5 things to be aware of, when buying LED bulbs

  1. Watts don’t matter

Let’s get this straight: watts didn’t matter, insofar as light intensity was concerned, for traditional incandescent bulbs either. The wattage displayed on the box was simply an indicator of how much energy those bulbs consumed. However, for those bulbs, the number of watts represented an accurate yardstick of how luminous one could expect them to be.

Things couldn’t be any more different with LED bulbs. Their whole point of existing is that they consume far fewer watts than their incandescent counterparts. Indeed, some producers try to give you a rough estimate of their comparable brightness. E.g.: an LED bulb that shines as brightly as a 60W incandescent bulb consumes about 8 to 12W.

However, if you really want an accurate measure of how bright your LEDs are, check out their output in lumens (lm). Check out the chart below – as it clearly points out, LEDs save up to 77% more energy, while providing you with just as many lumens.

watt lumen conversion led incandescent bulbs


Image source: RO Tech Aruba

  1. Not all LEDs work everywhere

As we’ve already told you, LEDs are cooler than incandescent light bulbs—and that’s all thanks to the design of their heat sink. The heat released into the heat sink is then eliminated into the surrounding air.

Now, this is all well and good for open lighting fixtures, but what if you want to place an LED into an enclosed or half-enclosed fixture? In this case, to prevent otherwise unavoidable heating, you will need to find compatible LED bulbs, which have been pre-approved for recessed/enclosed placing.

  1. Expect realistic savings

The savings bottom line for LED bulbs is very similar to that of a number of new technologies. The initial costs are bigger, but, in the long run, these technologies end up paying for themselves. LED bulbs are becoming less pricey (Philips sells a $5 model, for instance). They definitely produce less heat, and some manufacturers are even offering the option to control them with your smartphone.

It’s difficult to calculate exactly how much money you’ll be saving by switching to LEDs since many factors come into play. However, you’d likely be well advised not to expect massive savings on your very first power bills—unless you have a huge house, with a lot of bulbs and are completely turning it over from incandescents to LEDs.

cost savings led cfl incandescent light bulbs


Image source: Boston University

  1. Mind the kelvins

By and large, when shopping for LED bulbs for the home, you’ll want to look for fixtures labeled ‘soft’ or ‘warm’ white, which emit a light that’s very similar to that of conventional incandescents. Those which say ‘bright’ give off that colder, more impersonal light you often see used for store lighting.

That being said, there’s a scientific way to measure this, too. The color temperature of light is measured in kelvins. Though this might strike you as somewhat counterintuitive, the lower the number of kelvins, the warmer the light will be. If you want an accurate replacement for a typical incandescent light bulb, go for the 2,700-3,500 Kelvin range.

kelvins color light temperature led light bulbs


Image source: Smart Things

  1. ‘Dimmable LEDs’ can cost more

Alternatively, you might find that they won’t work in your house at all. Here’s why:

Incandescent light bulbs are compatible to dimming switches because the switch allows you to lower the amount of power that is provided to the bulb. In turn, the bulb gives out a lower amount of light.

However, LED bulbs simply don’t work that way. There’s no direct correlation between the amount of energy they are provided and the amount of light they produce.

Still want a dimmable LED? You’ve got one of two options:

  • Replace your dimming switch with a newer, LED-compatible one.
  • Find an LED make that’s compatible with traditional dimming switches.

For some of the best dimmable LEDs, check out the following video guide from CNet:

Is the Cree LED bulb really the best?

A simple Google search on Cree LED bulbs will reveal a host of positive signals: good reviews on CNet, a Forbes profile of the company CEO—not to mention a host of poignant, punchy ads. They all bid farewell to Edison’s invention, the light bulb, and introduce the Cree creation as the second biggest thing since.

But is the Cree LED bulb really that good? Is it better than its counterparts from Philips?

If profits alone are a marker to go by, then it might be worth noting that Cree is the manufacturer of America’s best-selling LED. In its first year on the LED light bulb market, the North Carolina-based company doubled its market share to $7 billion.

And, indeed, it’s all about the money. Traditional incandescents may cost $1 (a paltry sum, compared to Cree’s hefty $10 price tag), but each costs $7/year, at a usage rate of 3 hours/day. In the same circumstances of use, a Cree light bulb will only set you back $1/year.

What’s more, Cree LEDs last for 20 years, while incandescents only last a tenth of that. Cree LEDs, priced at $9.97 (for a 40W replacement) and $12.97 (for a 60W replacement) are cheaper than similar products from the competition.

Finally, the company that initially only sold its bulbs through Home Depot also managed to develop omnidirectional LED. It did this by redesigning the filament tower of regular LED fixtures. In that tower, they allowed 10 to 20 individual LEDs in various colors overlap, thus shining their light in all directions.

All you need to know about LED headlight bulbs

Retrofitting your car with LED headlights will only set you back a couple hundred dollars—but is it really worth it?

Full disclosure: we left it to the guys over at The Garage to install a full LED headlight kit, test it, and compare it to several types of halogen lights. They have the time, resources, and expertise for it. What follows below is a summary of their findings.

Feel free to check out their video below, in full—or read our summary first, then go back to the video whenever you have the time for it.

How LEDs work for headlights, as opposed to halogen lights

In a nutshell, halogen headlights are incandescent light bulbs placed in parabolic metal housing, off of which they shine more light. While incandescent lights are omnidirectional, LEDs are not. As such, the typical LED kit comes with several (usually 4) lights, with their respective heat sinks and power cables.

For ease of installation, those power cables can easily be connected and disconnected. However, bear in mind that, while the diode on the LEDs doesn’t heat up, the heat sink behind it does—and can be pretty uncomfortable even after a few seconds of use.

Why choose LED lights for your car?

Of course, because they allegedly last longer. Then, they also happen to be super bright—but more on that below. Overall, an LED kit for your car will consume less than the regular halogen bulb, which can clear up your electric system for other uses. It can also help your battery last longer.

How to install an LED headlight kit

The first step you need to undertake is figuring out just what bulb/system your car requires. To this end, most sites that sell LEDs will have a search function that helps you locate just the part you need. And if you don’t want to go through all the trouble of using an online car headlight bulb finder tool, you can also pick up the phone and call your LED store of choice.

After you’ve picked your LED kit, here come the following steps:

  • Remove the halogen bulbs. This should be pretty easy, even if it’s your first time opening the hood of your car. Of course, it also depends on how your engine bay is set up. When removing them, try not to touch their glass part with your fingers, since the skin oil can damage their projection abilities. If they still work, there’s no need to ruin them, even if you’re having them replaced.
  • Find a place for the heat sinks. These can take up quite a lot of space and get a bit unwieldy. Since they also heat up, you might be a bit worried about finding just the right spot inside the engine bay to tuck them into. Don’t worry—they’re not likely to cause anything to catch fire, no matter how much they heat up. But you might fiddle with finding the right position for them.
  • Make sure to screw your lights back in the right way. There’s usually a screw in your light fixture housing that aims your headlight the right way. You can calibrate your headlights at a certified inspection station, or just wing it at home. Your call, really.

LED headlights: Pros and cons

So, what was the guys’ verdict? Overall, LED headlights shine ultra-brightly, which makes them great as auxiliary lights (fog lights, camp lights, etc.). As main lights, the intensity can be a bit overpowering, especially for the other drivers.

To boot, their throw distance seems somewhat shorter than that of halogen lights. And, of course, you need to figure out where those darned heat sinks go, which ca be a real pain! All in all, for the time being, you might be better off sticking to halogens until LED headlights become more user-friendly, as well as better developed for use as dome lights.

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