Electricity Saving Tips For Homes And Offices

LED light bulbs buying guide

By on April 29, 2015

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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42 Comments on "LED light bulbs buying guide"

If you have any question or comment, please leave a message here. We try to reply to questions in the sequence they come in. We work from Monday-Friday 10AM-7PM. If we know the answer we try to reply to the question within 3 days.

Guest
nitin
June 30, 2015

Hi Abhishek
Please suggest me the LED wattage I need for the following rooms of my house

1) Drawing room 17.5 X 11 Sq ft.
2)Master Bedroom 13 X 11 Sq ft.
3)Bed Room 10 X 12 sq ft,
4)toilets 5 X 7.5 sq ft.
5)Study room 8.5 X 7 sq ft.
6)Balcony 17 X 4 sq. ft.
7)Balcony 4.5 X 8 sq ft.

Guest
Satpal Kundu
June 23, 2015

which brand is best for cove lights i mean warm white light LED strip, i need abt 7-8 mtrs

Guest
Somali Bajpai
June 19, 2015

Hi
Please can you give your contact details?

Guest
Sushama
May 15, 2015

Hi,

I am planning to install LED bulbs in our new home as an alternative to cfl bulbs, my intention is to use them only when we dont need more light from tube , so please suggest me
1. will a 9W led bulb enough for 14×11 room
2. 5w bulb is ok for 4×12 balcony space
3. 14w bulb enough for 10×13 room
4. 7W for 10×13 room

More importantly pls suggest me a good brand Philips/Syska there are many brands and I am seriously confused, your help will be highly appreciated.

Thanks in advance

Guest
Rakesh Kumar Pandey
May 31, 2015

You can use syska i can give you best price with 2 year warranty

Guest
Praveen
May 11, 2015

Hello Mr. Abhishek

I want to know that which LED products are best replacement for an office space.
Suppose in my office spaceMajor part of lights are of 18W and 36W, with few 28W and 40W.
Can you suggest some specific replacement LED models for these. That would be grateful.

Regards
Praveen Kumar

Guest
Rakesh Kumar Pandey
May 31, 2015

Ya you can use syska ,10W bulb is easy replacement of 18W & you can use 16W led tube light which is good replacement of 36W & 12W Tube Light for 28W & you can use.16W Tube is also replacement of 40W Tube .& i will suggest syska is best,for best price of syska you can contact me at 08527021151

Guest
Richard Babu
March 17, 2015

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

Guest
Prakash Thakkar
April 9, 2015

Contact Galaxy Lights – 9821024188

Guest
Richard
March 25, 2015

Thank you so much, its time to select good brand with your advises.

Guest
Richard
March 26, 2015

FYI

http://www.ledlightsinindia.com/information/indian-led-bulbs-comparison

Guest
Saloni
March 11, 2015

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.

Guest
Ramakrishna Chundru
January 7, 2015

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

Guest
Ravi SK
November 20, 2014

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

Guest
Augustine
August 11, 2014

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?

Guest
Augustine
September 12, 2014

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?

Guest
Augustine
August 11, 2014

one 18W light for every 80 sft approx

 
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