LED and how it differs from incandescent bulbs and CFLs?

LED lighting is highly-efficient and most eco-friendly lighting source in the market; what’s more, it offers so many varieties to choose from. We are here presenting helpful guidelines to help you make the perfect choice.

For years, people have only one style of light bulb – the incandescent. Over the time, there was need of energy-efficient lighting, and CFL bulbs came onto the scene, as a cheaper, more energy-efficient lighting option.

One step ahead, now we have LEDs offering benefits like low energy usage, low heat emission, and low impact on the environment when discarded.

Do you know lighting accounts for 10%-30% of a typical household’s energy bill in India? So, this is right time to make change, and go for highly efficient lighting – LED – and save money, energy and also our environment.

There are many types of LED bulbs are available in the market today. So choice is difficult and people generally wonder, how to choose the right LED bulb? We will solve your confusion, but let first have an overview of what is an LED lamp?

For over 150 years, 100-watt incandescent light bulbs have been in use to light up hallways and bedrooms while 60-watt Incandescent have been used in reading lamps and closets. They are well-known for producing yellow glow and became the most prominent electrical lighting choice for generations after generation.

Problem was that they were unproductive, and were wasting lots of energy as heat. It’s really sad that only about 10% of the electricity used is actually converted to light while 90% is given off as heat. They soon became obsolete as energy-efficient competition arrived.

CFLs have been around for a while, and become an energy-efficient alternative to incandescent bulbs. In its fluorescent technology, electricity is used to excite mercury gas inside the tube to produce ultraviolet light, which then passes through a coating of phosphor on the insides of glass tubes, giving off visible light based on the principle of fluorescence.

CFLs use much less energy compared to incandescent bulbs – about 75% less to produce the same amount light, but the main disadvantage to CFL lights is that CFLs contain toxic mercury in the bulb. Mercury is very dangerous heavy metal. Generally, this is not a problem, but if the bulb breaks, then proper cleanup and disposal of CFL bulbs is critical.

It’s time for making the best choice with the advent of new LED technology. LED bulb is next generation option in energy efficiency. LED bulbs are made out of clusters of small light emitting diodes instead of filaments, harmful mercury, or gases.

This technology has been around for decades and most commonly, it has been used as the small indicator lights on electronic devices. For now, LED bulbs are grouped in clusters with diffuser lenses to expand its adoption for home, office, and commercial use.

If you compare cfl and led bulbs, LEDs are highly energy efficient and use very little energy than incandescent bulbs and CFLs. LED technology is advancing rapidly with modern bulb styles available. They are more expensive than other lighting options, but the price of LED bulbs is going down every year as its manufacturing technology continues to improve. The main advantages of LED bulbs over cfl are low energy usage, low running cost and longest life time.

Performance of LED bulbs vs. Incandescent bulbs vs. CFLs:

First important thing to consider in comparison is performance.

LED light bulbs use only 2-17 watts of electricity that is about 1/6th to a regular incandescent bulb and 1/2 to CFLs. Traditional incandescent bulbs use a lot of energy to produce light however 90% of this energy is given off as heat. Here lost energy is money we are throwing away. On other side, using LED bulbs, you can save 85% in energy costs.

Low power consumption means far lower energy bills. Generally, lighting accounts for roughly 25% of the utility bill. So this is really a big deal, not only for individuals but also for larger properties like warehouses & factories, public schools, hospitals, local governing bodies, etc. which can hoard huge monthly bills. LED offers really big savings for their electricity use.

Comparison based on other important benefits that LED offers:

Life span: Another big advantage of using LED is that it lasts longer. Our GlowUP LED bulbs last for an average of 50,000 hrs, around 15 years (at 9 hours/ a day) under normal household use. This is roughly 30 times longer when compared to incandescent bulbs as well as 5 times longer than CFLs.

Big saving of energy and money: LEDs are initially expensive, but the cost is recovered quickly in electricity and replacement savings in the long term. It offers considerable ongoing savings for many years to come, as LED bulbs last for an average of 50,000 hrs means no hassle of replacing bulbs. On considering its low-power usage and long life, it helps you save a lot than incandescent bulbs and CFLs.

Highly durable: LEDs are extremely durable; as they do not have a filament means they can work even if dropped or fell down like incandescent bulb. Being solid with aluminum body, they also hold up well to jarring and bumping.

Less heat: LEDs don’t get hot, even after being on all night. They just feel warm to the touch while Incandescents and CFLs get really hot to work by their very nature. LED lights do not cause heat build-up. They come with metal heatsinks to draw the heat away from the LED chip itself. That means it’s safer to operate as well as it can cut energy costs along with cut air conditioning costs in the home, preventing heat build-up.But if the heat sink is not perfect in size, poorly connected or of a poor design, the LED will be overheated and burning out. Here thermal management is the single most important factor in the successful performance of an LED product over its lifetime, as higher the temperature at which the LEDs are operated, the more quickly the light will fail and the shorter the useful life.

Eco-friendly: LEDs notably reduce carbon emissions, so praised as the best eco-friendly lighting option. Every year, power plants using Incandescent bulbs emit 80 million tons of CO2 into the atmosphere for generating electricity to light US homes. Now replacing all those bulbs to LED, carbon emissions is reduced to only 12 million tons comparable of taking 2,500,000 cars off the road.Even LED bulbs don’t contain harmful mercury like CFLs. Mercury is a toxic heavy metal that damages the environment as well as becomes poisonous when breathed in by humans. As LEDs use low power, there would be lesser demand for electricity that resulted in less power plants means less pollution.

CRI – quality of a bulb’s light: Color rendering index (CRI) is important factor for any led lighting product. General use bulb for home requires CRI of 80. With High CRI > 82, Charlston’s GlowUP LED lamp helps you see the actual color of the objects more accurately.

Suitable to decorate any corner: LED bulbs would be nice lighting choice for effect and decorative purposes. As LEDs lights are directional, they are excellent for lights under cabinetry, in the kitchen over your workspaces and over the home office desk.

Quick light: LEDs are instant on like incandescent while CFLs take a minute to warm up on turning on.

Dimming Capability: The main difference between cfl and led bulbs is that, CFL lamps cannot be dimmed. With dimmable LED bulbs, you can not only save money but also increase life span of bulb.

Calculating the cost of electricity:

Here is given a simple example to know how much you exactly save for using LEDs. For this, you must calculate the costs of electricity to run light bulbs.

At first, take scenario of 3 bedrooms, each having a light bulb in the ceiling. Fix 60W incandescent regular bulb in first bedroom, a 20W CFL for the second, and 9W GlowUP LED bulb for the third one. All these bulbs would give the same light level in the room.

Now to calculate the cost of running the light bulbs for a year, first you have to make some assumptions like usage of light bulb and how much are you charged for electricity?

Suppose light bulb in your room is used for about 6 hrs a night, means about 2000 hrs of use every year. Next assume that you pay for electricity 7 Rs. (Indian rupees) per kWh( 1 Unit). Also, get the bulb’s wattage in 1000W = 1kW means 40W bulb is 0.04kW.

Use formula: hrs x Rate x Wattage = Total yearly cost.

So, a yearly running cost
for the 60W incandescent bulb is 2000(Hrs) x 7(Rs) x 0.060(Kilo Watt) = Rs. 840/-
for the 20W CFL it is 2000(Hrs) x 7(Rs) x 0.020(Kilo Watt) = Rs. 280/-
for the 9W LED it is 2000(Hrs) x 7(Rs) x 0.009(Kilo Watt) = Rs. 126/-

You can use this formula for any types of bulbs.

Another way to count on savings of LED lamp is take a quarter of your bill – did you know that lighting account for 25% of a home’s electricity usage. Now, reduce that quarter portion by 85% if you want to go from incandescent bulbs to LED or by 50% if you want to switch from CFL to LED.

How to calculate total cost of replacing bulbs?

What if there will be any replacement of light bulb, you couldn’t get the right figure based on common usage. Knowing cost of replacing bulbs over a particular period helps you count exact saving for LEDs.

As claimed, our LED bulbs last 50,000 hrs, CFLs last 5000 hrs, and the incandescent bulbs last only 1000 hrs. Suppose there is 2000 hrs a year of usage; then within 20 years, you’re only going to have 1 LED bulb, while you need 8 CFLs and 40 Incandescent bulb.

Another important thing is the money spent on light bulbs. On assuming prices stay the same, 9W LED Bulb costs 750 Rs. and its 20w CFL equivalent costs 200 Rs. and 60w incandescent bulb costs around 20 Rs. That means over a 20-year period 1 LED bulb will cost 750 Rs., 8 CFLs will cost 1600 Rs and 40 incandescent bulbs will cost 800 Rs.

Cost of electricity per year to run those light bulbs, as calculated above

9W LED Bulb = Rs.126/yr
20W CFL Bulb = Rs.280/yr
60W Incandescent Bulb = Rs.840/yr

Cost of electricity over 20 years:

126 x 20 = Rs. 2520 for LED
280 x 20 = Rs.5600 for CFL
840 x 20 = Rs.16800 for Incandescent

Total cost over 20 years (Cost of electricity over 20 years + Cost for the bulbs used within 20 years):

Rs. 750 + Rs. 2520 = Rs.3270 for LED Bulb
Rs. 1600 + Rs.5600 = Rs. 7200 for CFL
Rs. 800 + Rs. 16800= Rs. 17600 for incandescent Bulbs

Check the Incandescent vs. CFL vs. LED light bulb comparison chart below showing annual running cost, energy usage and lifetime.

Role of Lumen in lighting output as well as efficiency:

Lumen is unit to measure the total amount of visible light that your bulb and other lighting object produces. You can easily compare lumens between all incandescent and CFL bulbs, as higher lumens on the box, the brighter the bulb’s light output. But it is meaningless if you compare lumens between an LED bulb and a CFL to an incandescent bulb. On measuring lumens, you also have to consider useful lumens. If a light bulb emits light in every direction similarly over and beneath, then light that going up can get trapped in the light fitting and totally wasted.

It is reported that about 50% of light emitted from a CFL or incandescent bulb is trapped inside the fitting and never makes it out. That trapped light is just gets absorbed and wasted as heat. That means from all the lumens that bulb produces, only about half actually lights the room, these are called as the useful lumens. When it comes to LED bulb, its little LED chip is mounted to the body of the bulb and all the light coming out are all pointed in the one direction, basically pointing down. As bulbs in your ceiling are pointed down, all of the light produced by the LED bulb makes it into the room.

See the Incandescent vs. CFL vs. LED light lumens chart:

Wattage	Lumens	Useful Lumens
LED 9W	800 lm	800lm
CFL 20W	1000lm	500lm
Incandescent 60W	1000lm	500lm

Here you can say that the 9W LED is higher in light output levels to the other two. All the lumens produced by LED bulb are useful lumens, while only about half of the lumens from the CFL and incandescent are actually usable.

Efficacy is another important thing to decide the performance of the LED bulb in terms of lumens. It points out effectiveness of the light bulb at converting electricity into visible light based on watts used by the object while turning on. Thus, efficacy is total lumens per watt. For ex. our 9W light bulb comes with lumens of 800 has an efficacy of 90lms per Watt.

What to look for Quality in LED Bulbs?

Light quality and temperature are also important consideration to make on comparing bulbs. Both important things are measured by CRI and CCT respectively.

CRI – Color Rendering Index: CRI is a measure of light quality, showing how well a light source replicate color to the human eye relative to daylight. White light is made up of all the colors in the light spectrum. We can see the color of every material object when light being thrown on it. Natural daylight has the highest CRI rating, while artificial light sources can’t produce all the colors of the light spectrum. CRI of 80 is the standard requirement for general home use. With CRI > 82, Charlston’s GlowUP are best to render natural colors. Even some well-known retailers with colorful fabric and wares are switching to LED bulbs and are perfectly satisfied with CRI score of > 80.

CCT – Correlated Color Temperature: CCT is measured in Kelvin to refer to the warmness or coolness of the white light that bulb produces. CFLs and LED bulbs don’t get as hot as incandescent bulb. The temperature is linked to the warmness or coolness of the light – higher the temperature cooler the light looks. LED bulb listed with 3000K doesn’t actually heat up to 5000°F, but it will still give off a warm light just like an incandescent so color temperature is important. As being Cool white, our LED bulbs have 5300K- 5600K temperature. Some LED bulbs have more than 6000K CCT, which make the light more towards bluish rather than white.

How to buy the perfect LED bulb?

Above mentioned details help you get perfect idea about how better is LED bulb, compared to other lighting source. If you are fully convinced, then your next step would be purchasing of LED bulb, but wait, LED bulbs are available in so many varieties to choose from. To make the right choice, consider important factors that affect making of LED bulbs. So many factors help to differentiate the value of LED bulbs from each other. Just checkout carefully and pick the best LED bulb for your home, office, or other purpose according to these factors.

Quality of the LED chip: The performance of the LED light bulb is mainly based on LED chip, so next important thing need to be considered here is type of LED chip used. High quality chips last longer and depreciate less over time, both for light output as well as light quality; however you have to pay more for that quality. So beware of LED bulbs made using chinese LED chips.

Lumens: The next step would be to calculate its lumens per rupee – How many lumens does it produce and how much does it cost? For ex. an LED bulb is 800 lumens and costs Rs. 750 (800/750) = 1.06lms/rs. The higher this ratio is, more light the bulb emits.

Lifespan of Bulb: Another important thing is lifespan in hours. Charlston’s LED bulb GlowUP lasts 50,000hrs. So if you consider daily use of 8 hrs, bulb may last 17 years, and for daily use of 12 hours, bulb may last 11 years. The life of bulb also depends on the heat sink used to draw heat away from the chip and LED driver. In addition to good heat sink, GlowUP is dimmable, which extends its life to last longer.

Color Temperature: Modern bulbs are available in different color temperatures – in a unit called Kelvin (K). A warm yellow light offer lower color temperature with a lower Kelvin value, giving a comfortable atmosphere. While cool blue light offer higher color temperature with a higher Kelvin value, which is more energizing. If you prefer clean look, modern, brighter feel of a cool white lamp, over traditional yellowish color of warm light, then GlowUP is for you.

Dimmability: The amount of light in a room helps to create the suitable ambience, and it can be controlled with dimmable light bulbs including dimmable LEDs. You can easily turn the amount of light up or down via a dimmer switch. Dimming not only saves energy consumption but also extends bulb life, as the power to bulb is reduced, So must consider it while selecting.

The significant difference between branded and non-branded LED bulbs is that: non-branded or chinese bulbs have lower quality power supply, lower lumen per watt output and lesser life span. And this is the reason why there is a large price difference between different LEDbulbs.