Electricity Saving Tips For Homes And Offices

LED light bulbs buying guide

By on March 6, 2014
This article is also available in these languages: hi Hindi

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LED is the latest buzzword in the lighting industry. Looking at the way things are moving, LEDs surely look to revolutionize the lighting market in future. Small bulbs that were used as power indicators for appliances, look to light up the whole living space now. Technology improvements have made LEDs useful for home and office and have also made them much affordable now (still expensive as compare to CFLs or incandescent bulbs). Several manufacturers have come out with luminaires that use LED for lighting. These luminaires are available for all purposes: spot lighting, indoor lighting, outdoor lighting, street lighting, floodlights, garden lighting, general purpose lighting, etc. With this guide we would like to provide you information that can help you choose the right kind of LED light for your purpose.

LED Bulb

What is LED and how it differs from other types of lights?

LEDs are a member of type of lighting most commonly referred as solid-state lighting.  This type of lights illuminate when current passes through a semi conductor material. They produce more “light” and very less “heat”. In comparison an incandescent bulb lights up when the filament in it heats up. Thus it releases 90% of its electricity as heat. CFLs or tubelights light up when electricity current is passed through tube containing gases. CFLs also release heat but less than incandescent and more than LEDs.

The other major difference is that LEDs are unidirectional (or emit light in a specific direction) but incandescent and CFLs emit light in all directions.Bulbs

Image Source:

 http://www.energystar.gov/index.cfm?c=lighting.pr_what_are#what_are

What are the different parts of LED bulb?

Typical LED bulbs contain one or multiple LED chips mounted on a circuit board that is programmed to control the LED lighting. The whole thing is mounted on a heat sink to manage the heat generated from LED.

What are the benefits of using LEDs?

  1. The biggest benefit of using LEDs is their life. They have a life of 25000-50000 hours of usage. So if it is used for 4-5 hours a day, it can run for 15-25 years without needing a change.
  2. Good quality LED bulbs are maintenance free. So they are like put it and forget it.
  3. They can give better output (brightness) or lumens per watt if beam angles are lower (more on beam angles in the details below).
  4. The light output of LEDs remains constant through its life only decreasing towards the end of their life.
  5. They do not flicker even when dimmed.
  6. Lot of them come with good warranty (of up to 10 years) which means you investment now will last for up to 10 years!
  7. They are eco-friendly. They do not use mercury (used in CFLs), which is harmful for environment.

What are the drawbacks of LEDs?

  1. LEDs are unidirectional or emit light in a specific direction. So they cannot light up the whole area (of a room) unless diffusers and reflectors are used. Thus they are excellent for spot lighting but not as great for general-purpose lighting.
  2. Although LED chips have a long life but the life of LED bulbs depend on how well the heat sink and the circuit is designed. A poorly made LED bulb may not last longer than a year (if right heat sink and capacitors are not used: http://www.electronicsweekly.com/blogs/led-lights/2009/02/led-life-expectancy.html). In many countries LED bulbs are rated based on their performance. In India it is better to buy LED of a good brand or buy one that comes with a longer warranty.

What are LED beam angles and how to use them?

As we said, LEDs are unidirectional or emit light in a specific direction, it is important to figure out the right spread of a LED light in degrees before using it. This spread is mentioned on LEDs as beam angle. Typical beam angles that are available in the market are 15, 30, 45, 60 and 100 (with some very few with 120 and 180 as well).

Beam angles less than 30 are excellent for spotlights. Their output (brightness) or lumens per watt is highest available in the market. Most of them have wattage of less than 5 and are of great use in Shops (where focused lighting is needed on products), Workshops where a specific work is to be done or at homes where specific area has to be focused with decorative lighting. One or more such lights can be used near walls as spotlights.

Beam angles greater than 30 are suited for high power LED lamps usually used for downlighting. They can be put on ceiling to illuminate an area in a room. They typically are of more than 5W rating and multiple such downlights are to be used to illuminate a room.

A 30-45 degree beam angle is good if the ceiling is high (more than 10-11 ft). If the ceiling is less than that, then it is better to use 60-100 degree beam angle. Based on requirement, multiple such downlighters have to be used and kept 3-4 mts apart from each other to get appropriate lighting.

Lower beam angles are also good for outdoor lighting and street lighting purposes where they can be excellent replacement for halogens that consume a lot more electricity as compared to LEDs. Housing societies can benefit by using LED street lights.

The increased beam angles are achieved by putting reflectors and diffusors, and the biggest drawback for this is that the lumens (or brightness) decrease as beam angles increase. So a LED bulb with higher beam angle may give same brightness as a CFL for the same wattage.

How do some LED bulbs available in market have more than 120 beam angle?

Lot of LED bulbs available in the market have diffusors to disperse the light at greater angles. This makes sure that the light spreads across the room. But their brightness will be equivalent to a CFL bulb of same wattage. These are generally designed as replacement for CFLs and incandescent bulbs.  The benefit of these bulbs is that they are long lasting and ecofriendly.

What other factors should be considered while buying?

As we discussed in our article on task based lighting, color temperature of the bulb should be considered based on the mood to be set in the room. LED bulbs are available in various color temperatures: Cool Daylight (White) to Warm White (yellow). Choosing the right one based on the mood to be set in the room is important.infographic14

References:

http://www.energystar.gov/index.cfm?c=lighting.pr_what_are#what_are

http://en.wikipedia.org/wiki/Light-emitting_diode

http://en.wikipedia.org/wiki/Solid-state_lighting

http://news.cnet.com/8301-11128_3-20023357-54.html

http://www.electronicsweekly.com/blogs/led-lights/2009/02/led-life-expectancy.html

http://www.led-depot.com.au/beam-angles/


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There Are 28 Comments

  1. Richard Babu says:

    Hello Mr. Abhishek,

    Thank you so much for another informative and essential article for today.
    I’ve also planning to install LED lighting for our newly constructed house.
    Kindly advise, does LED affect our vision with its radiation??
    When I surfed there are lot of controversy, hope this is an important point to be discussed along with energy saving.

    Richard

    • Abhishek Jain says:

      Hello Mr Richard,

      LEDs are unidirectional and produce a lot of brightness. So if you buy a LED luminaire then you have to make sure that it has the right lenses and diffusers (milky white coverings) so that it is not pinching to the eyes. They can impact vision only if they are too bright for your eyes. If you get those with milky white covering, they would not be difficult to the eyes.

  2. Saloni says:

    Thanks Abhishek for such a detailed blog. Was really useful.

    These days Ever Ready n Havells are also producing led tube lights. Ever Ready is promising high lumens etc. Can you plz tell which would be better brand to buy quality n economic too.

    • Abhishek Jain says:

      Hi Saloni,

      Which models of tubelights are you comparing? You should compare lumens/watt. These days LEDs with 110 lumens/watt are quite commonly available. I would say Havells is a great brand.

  3. Ramakrishna Chundru says:

    Hello Abhishek,
    Are LED bulbs are compatible with MSW type of inverters?
    -Ramakrishna

    • Abhishek Jain says:

      Hello Mr Ramakrishna,

      MSW inverter have high harmonic distortions. LED bulbs themselves generate harmonic distortions. I do not think there will be an impact of using MSW inverter for LED bulbs. You can also check this video: http://www.youtube.com/watch?v=BHYNW7UEMzw

  4. Ravi SK says:

    Hello Guys,

    Take a look at Dhaksha AC powered 18W Smart LED tube light. It features, dimming, remote control and networking capability as the need may be. It is reliable and affordable.

    http://www.gtd-labs.com

  5. Augustine says:

    Hi Abishek,

    Am planning to install LED lights in my house and the electrician suggested following lights
    LED 18W MYSTIQUE MAKE INDIAN REWA SERIES SQUARE DOWNLITER HALF WHITE LIGHT 4K WITH DRIVER SET (Rs.1200) – 1 light for approx 80 sft and
    LED OSRAM 4.5W PARATHOM SPOT FITT SS FINISH SQUARE DEEP RECESS FITT (Rs.750) – for spot light here and there

    Do you know whether these are good brands and can we go for it?

    • Augustine says:

      one 18W light for every 80 sft approx

    • Abhishek Jain says:

      Hi Augustine,

      18W CFL will give light output equivalent to a 23-25 W CFL. So 1 light for 80 sq ft sounds fine. Although I have not heard of the brand. Most Indian brands are just assembled in India. The bulbs and the drivers are imported. As long as the make is a reputed make like Cree, Osram or Samsung, it should work well.

      Also you should go for downlighter if it is mostly for decorative purpose. For regular use, you should go for a LED tubelight. Line sources of light are brighter than point sources for the same wattage. That is why Fluorecent tubelight like T5 (which is of 28 W) gives much more light that similar wattage CFL. LED Tubelight of 20-22 Watts will give similar amount of light as a regular tubelight.

      Also 4.5 watt for spot sounds on a higher side. 2-3 Watts of spots give quite a lot of light. You can compare them in a store. Osram is a great brand.

      • Augustine says:

        I was suggested to use LED 15W/mt HI BRITE FLEXI STRIP and LED 5W/mt FLEXI STRIP ( BLUE, WARM WH & PINK) for cove lights in the ceiling. I think this is mostly for decorative purpose. Do you think, this is appropriate size needed or should I go for low wattage strip lights?

        • Abhishek Jain says:

          5 W/mt sounds more like decorative light. 15 W/mt one would be quite bright. However it all depends on how much light you want in the room. 5W/mt sounds good to me just for decorating.

  6. Praveenraj says:

    Hi anhishek ,

    Thanks a lot for your revert .

    I am actually planning to buy LED Downlights which will fit into false ceiling . I Have seen Philips , havells and rainbow . Specifications are not with me . I need to check on them .

    In LED is the driver the key component or both lights and driver imp. Some local brands are giving led lights with Philips drivers .whats your opinion

    Reg
    Praveenraj

  7. praveenraj says:

    Hi Abhishek ,

    Thanks for the info on you website

    We are currently installing LED lights in our house , Ceiling height after false ceiling is around 9Ft.

    Wanted to check if 12 W LED is enough in a 22.3″ x 5.5″ hall .I am installing 7 12W lights and 2 3w warm lights under TV unit.

    Kindly suggest any brand which I can choose from

    Reg
    PraveenRaj

    • Abhishek Jain says:

      Hi Praveen,

      Do you have specifications of the 12W and 3W LED lights? It will be good to know their:

      1) Lumens output
      2) Make (is it a Osram or Cree make LED or a chinese one)
      3) Beam angle.

      I would suggest that you look for options of using LED tubelights as tubelights are brighter as compared to bulbs for the same wattage. You can look at SSK, Philips, Osram, etc (several local brands also use Osram, Cree or Samsung make LEDs which are good and cheaper).

  8. Jaideep Sinha says:

    I wanna buy a Syska LED 5W bulb.. Plz let me know is it worth buying or not?

  9. lewis11c says:

    Thanks for the guide

    • Abhishek Jain says:

      You are welcome. Do sign up for our newsletter to get updates.

      Regards,
      Abhishek

      • amar says:

        Abhishek

        Excellent write up! please keep them coming.
        I’ve planned the following for my new house, would like your comments/recommendation

        Master & Guest Room:
        18W Skyska LED tubelight – both room around 100sqft
        what beam angle do i look for?
        Alternate as a LED bulb ( or should CFL suffice?)
        Do you think an alternate bulb is mandatory in case of low voltage ??

        Open Kitchen & Dining
        I’m not keen on a tubelight here, what would be best option?
        or is LED tubelight best fit here too?
        what beam angel would be good

        Living room:
        im trying to avoid a tubelight here, trying to get one of those indirect light
        something like these
        http://www.snapdeal.com/product/learc-designer-lighting-modern-wall/444697884
        what watt bulb would suit those? keeping in mind the beam angel so the living room decently lights up

        Foyer:
        Dont want to brighten this area too much, what kind of LED would be best suited at the entrance?

        Bathrooms:
        something with indirect light, what watt is best fit here?

        Balcony/utility:
        Does 1W LED good enough?

        Thanks for all your articles! it’s helped us a ton!!

        Cheers
        A

        • Abhishek Jain says:

          Hello Mr Amar,

          LED tubelights have much wider beam angles (about 150-160) which means they can cover most of the area. An 18 W LED tube will be good enough for 100 sq ft room.

          Bulb and LEDs will give much lesser light as compared to a tubelight. If you are used to having tube lights in your room, then blub/LED bulbs will not have that much light.

          Alternate bulb is not mandatory for low voltage. LED tubes should light up at low voltage as well.

          Even for kitchen & Dining, LED tubelights will have more spread so it will appear brighter as compared to CFL or LED bulb. But if you are keen on LEDs then you should consider LED down lighters that can go in the false ceiling and throw a spread of light on the floor. LEDs (bulbs) may not work well on side walls. Its better to have either down lighters (on ceiling) or LED tubelights (on side walls).

          If you plan to go for designer lights on side walls, then CFLs will be best for them. Else again in living room you can go for downlighters/panel lights or strip LEDs for decoration.

          You can also try designer LED downlighters for bathrooms or living room. LEDs are goo when installed on ceiling or if install on the wall they are good as spots. Unlike CFLs they will not have 360 degree spread and that is why installing them as downlighters makes more sense.

          Also 1 W LED will be good for a spot light, but I doubt that it will cover decent amount of area. You will need at least 5-7W LED bulb for the balcony.

          • jishnu roy says:

            Hi Abhishek,

            Is Megaway a good brand for LED light products, They seem to be available in all e-commerce sites and decently priced.

            Thanks in advance.

            Jishnu

          • Abhishek Jain says:

            Hi Jishnu,

            I have not heard much about the brand. So I cannot comment on it. There is a wide range of quality of LEDs available in market. We are just trying to find a full proof way to analyze it. For now I can just give a few pointers:

            1) Make sure that the warranty/guarantee is long enough. I have heard of up to 3 years warranty on luminaires.
            2) Make sure that the power factor of the luminaire is more than 0.9 (this should be in technical specs).
            3) The aluminium casing of the luminaire should be robust and sturdy. Good workmanship shows a good heat sink design. LEDs can fail if temperature of LEDs increase more than 60 degrees. A good heat sink ensure that the temperature does not rise.
            4) If the LEDs in the luminaire are Osram or Edison make then they will last long. Osram is the best.
            5) Additionally there are several certifications like LM-80, LM-79 that are provided to manufacturers who follow quality initiatives.
            6) Make sure that Lumens/watt of the product is good. Anything less than 100-110 should not cost more than what a CFL costs :).

            You can get very cheap LEDs completely manufactured in China but of very bad quality. For now I can just give you some theoretical concepts (as mentioned above) to analyze. We are trying to figure out a practical and easy way to identify right LEDs.

        • AYUSH says:

          It Is woth buying you can contact me for syska products at best price 08527021151

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