Electricity Saving Tips For Homes And Offices

Energy Efficient Lights – use CFLs, T5s and LEDs

By on March 6, 2014

Lights Lighting consumption constitutes about 30% of residential consumption as per a study by Ministry of Environment and Forest in India. Its contribution in your electricity bill may vary from 10-20% depending on your total bill. Although it may not be a major contributor in the electricity bill, the energy efficient options are fairly simpler to implement and provide higher rate of returns.

Latest technical advancements in lighting provide with a lot of options for energy savings today. The energy saving lighting options are a little expensive compared to the old incandescent options and old tubelights, but the payback time for them considering the savings it provides is quite short depending on the usage (mostly less than a year for average usage). Also the life of the new energy saving lighting options are far better than those of the old lights, which makes them much more attractive. There are several lighting options that are available in the market which are discussed below:

1) Incandescent Bulbs: The traditional yellow light bulbs which were available in various variants: 40W, 60W and 100W, are the most inefficient in terms of energy consumption. 90% of the energy they consume is lost as heat and only 10% is converted into useful light. Although they are still available for cheap (Rs 10/-) and a lot of households still use it, but they are the energy guzzlers. Many countries in the world have stopped producing them. Even if they are still there in working condition in several households, it makes a lot of sense to replace them with energy efficient options just from a cost saving perspective.

2) Tubelights: The fluorescent lamps are better than Incandescent bulbs (50-70% better in providing same amount of light) and they have been there in the market since quite some time. It started coming in the form of tubelights (something which most of us have known since our childhood) and later graduated to come in form of CFLs. A typical fluorescent lamp has a ballast (to stabilize the current through the lamp) and a tube. In past tubelights used to come with electromagnetic ballast which caused the lights to flicker on start. Now a days we get electronic ballast which prevents the fluorescent lamps to flicker. Electromagnetic ballast consumes for electricity than an electronic ballast. Most tubelights today have electronic ballast. Tubelights are also available in various variants: T12, T8 and T5. These numbers represent the thickness of the tubelight. The smaller the number, the higher the efficiency. T5 tubelights with electronic ballast are the best available fluorescent tubelight options in the marketA T12 tubelight with a electromagnetic ballast typically consumes 55W of electricity but a T5 with electronic ballast will consume only 28W of electricity (comparison is for a 4 feet tubelight). Thus a T5 provides about 50% electricity saving over a regular T12 tubelight. T8s are typically 38W tubelights and are better than T12s. Although T5s are little expensive, the payback is within a year. Also their life is quite good and they last for 3-4 years at least. Many companies give 1-2 year replacement warranty on T5s. Thus the payback happens within the warranty period.

3) CFLs: CFLs have been regarded as the best energy saving option in our country since quite some time. CFL is a variant of fluorescent lamps (or tubelights) but has a different application. CFLs act as a point source of light (light originating from one point) whereas tubelights are line source (tubelights have bigger lengths) and thus the area covered by tubelights is lot more than that of CFLs. This is the reason why a lot of people feel that CFLs produce lesser lights than tubelights. Even with equal wattage (2x14W CFLs) the amount of light is felt lesser than a T5 tubelight (of 28W) because of CFL being point source. CFLs being compact in size provide options to create smaller (lower wattage) bulbs that can cater to locations where tubelights provide extra brightness (more than required). CFLs provide up to 70% energy savings over a typical incandescent bulb. Although a little more expensive than a incandescent, payback happens within a year.

4) LEDs: LEDs are the latest and most efficient lighting option which is available in the market. Their electricity consumption is 50% less than that of CFLs and fluorescent lamps for the same amount of light. LEDs also are long lasting with a life of about 10-25 years and their performance remains the same throughout their lifetime (Tubelights and CFLs get dim with time). Although a little expensive (with a payback of about 2 years), the benefit with LEDs is that it is maintenance free. Once installed, it will not need any repair of change for at least 10 years. A lot of companies manufacturing LED options give replacement warranty for up to 10 years which makes the option even more attractive. The only drawback of LEDs is the angle covered by the light. CFLs and tubelights provide lights in 360o where as for LEDs the angle depends on the kind of reflectors used in the bulb.  Some do provide larger angles so that is something that should be checked before buying.

Wattage of the bulb or tubelight has been traditionally used as the measure of amount of light produced by it, but watts does not represent the actual amount of light produced.  The amount of light produced is represented by a term called lumen. So to compare two lights, one should compare the lumen of output and the angle of delivery of light. Wattage just helps one estimate the power consumption.Infographic9 Infographic12 infographic14

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There Are 21 Comments

  1. SK Sharma says:

    Do we get cfl / led tube lights in India . If so, what are the prices

    • Abhishek says:

      There is no difference between regular tubelight and CFL, as both use the florescent tube technology. LED tubelights are there.

      Regards,
      Abhishek

  2. neeta says:

    Hi, I live in a Govt quarters. Usually when a room is not used, we switch off the tubelights and switch it on when we require it. It happens quiet a few times in a day. I get a electricity bill of Rs.1600 and above inspite of not using AC, geyser, water purifier. My use of microwave is just restricted to just 2-3 times a month, so not more than half an hour in total. The washing machine, fridge, mixer, 4 tubelights, 3 CFL lights, TV (for 3-4 hours a day) and the computer (1 hour a day) are used on an everyday basis. My previous residence inspite of using AC, geyser, water purifier as well as all the other household items, the amount of bill justified the usage. I have a feeling that I am charged wrongly. Am I right? Can I go ahead with a complaint to the electricity department. Or is there anything wrong in the way we use it? kindly guide

    • abhishekjain203 says:

      Hi Neeta,

      Which city do you live in? Also how long do you use various appliances in a day? And finally what size fridge do you have?

      Regards,
      Abhishek

  3. dvsquare says:

    Hi, I have a living room 12*16, our interior designer has already made a provision for 2 strip lights on the opposite sides on the false ceilings.
    Apart from that, both the false ceilings (1.5 ft wide), have provision of 3 each (total 6) LED lights, and have been told to buy 5W warm white light for them, total of 6 * 5W warm white for our living. I wanted to ask whether 6 warm white LED lights of 5 or 6 W will be good enough for illumination ? Will that be good enough for occasional reading?

    • abhishekjain203 says:

      Hi, Do you have more details mentioned on the LED lights? As in how many “Lumens” does it generate? Lumens is the measure of brightness as opposed to watts. Having said that 6 lights of 6 Watts means 36 watts of lighting. Even if the LED bulbs are as good as fluorescent lamps (CFLs) in terms of brightness, it should be good enough for the room size you have mentioned (unless you like your room to be very bright).

      Regards,
      Abhishek

      • dvsquare says:

        Thanks for your reply.
        No, I don’t have much details, I have to go and buy now. So, I wanted to know what to keep in mind while buying.
        Since, its a living room, suggested is “Warm White” light, 6 numbers of 5-6 watts each. We don’t want very very light room, but it should be good enough for a living room ambience, and should not create problem in occasional newspaper etc reading.
        Also, do you have any suggestion on which brand to buy for these paneling lights?
        In market, the brands are too many and most of them are unheard of, so its difficult to make decisions. Sometimes, wipro or philips doesn’t make all type of lights and sometimes all the shopkeepers doesn’t keep them.
        Thanks again for your reply.

        • abhishekjain203 says:

          Hi,

          I would suggest you to look at the lumens of the bulbs. Lumens represent the brightness. For your size of room you would need about total of 4500-5000 lumens (please refer: http://www.bijlibachao.com/Lights/how-much-lighting-is-good-lighting-for-a-room.html). This is the brightness that you can get from 2 regular tubelights. And 2 tubelights will be more than enough for you to do reading occasionally. Now ideally equivalent LED wattage (combined) to get brightness of that amount should be about 40-45 watts (in total). But I would suggest that you look at the lumens when you buy a LED bulb. Also do read this as well: http://www.bijlibachao.com/Lights/led-light-bulbs-buying-guide.html.

          Manufacturers like Phillips and Havells do make LED lights and you can check their websites to find out more. I would not recommend you going for unbranded LEDs or lesser known brands unless you have received recommendation for a specific brand from someone known. There are lot of cheap and bad LEDs in market that do not last long. The biggest benefit of LEDs (as compared to fluorescent lights) is its life. And if they do not last long then it is better to go for CFLs or fluorescent lights. Or else you should have a return warranty for at least 10 years on the product. So lumens and warranty are something that you should definitely look for.

          Hope this helps.

          Regards,
          Abhishek

          • dvsquare says:

            Great, thanks abhishek.
            I got the lumen thing, so basically I need to check for around 700 – 750 lumens per LED panel light (total 6 LEDs).
            I will check that and not only the wattage.
            And in our bedroom, which is equally big, in the false ceiling, the space for 2 lights are given, and being suggested to buy 2 LED lights, each of 15 W, and of “white light”.
            And I will remember to buy branded ones like philips or wipro or havells, depending on the budget, because most of the lesser known brands come with 2 year warranty, but then we are looking for a lifetime of 10 years atleast.
            Also, what about spot lights 1w, any specific brand there ?
            Similarly in case of strip lights also, I am confused, as which brand to go for.

          • abhishekjain203 says:

            If we compare products in terms of lumens output, LEDs luminaries that have wider angles (or that are not spot lights) do not have much benefit over fluorescent bulbs/tubes. The wider the angle at which an LED luminaire delivers light, lower is its efficiency in lumens/watt. Their major benefit is that a CFL may last just for a year or two but a LED bulb may last for 10-15 years. On top of it CFLs are harmful for environment while LEDs are not. Ideally LEDs are like put it and forget it. But cheaper LEDs available in the market have bad circuit designs that fail early. So buying the right one is most important. The only brands that I am aware of are the bigger ones. So I may not be able to help you on that.

            As far as Spot lighting is concerned, nothing can beat LEDs in terms of efficiency. 1W of spot lighting would be far efficient that any other spot lighting options available in the market. So you will surely get more value for your money with LED spot lights.

          • dvsquare says:

            Thanks Abhishek for lot of useful info.

          • dvsquare says:

            Hi Abhishek,
            One more query about the spotlights.
            Today, when I went to purchase the spot lights, I opted the philips one and but they were 2W, even wipro ‘garnet’ was 2W, but other indian brand called pasolite and another one was 1 W.
            And for that shopkeeper told that, LED is 1W only and 1W is wasted in driver, which happens in other brands also, but philips & wipro write full 2W on their box.
            Was he correct in this explanation?
            I seemed to believe in his saying and opted for 2 W philips LED spot light.

          • abhishekjain203 says:

            Ideally the power rating of the bulb should be the total power consumption of the assembly. It is strange if it is not the same. But I think it is better that you opted for philips.

  4. rakesh reddy says:

    in my study room which bulb is more efficient(bright) whether cfl or t5 tube lights

    • abhishekjain203 says:

      Hello Rakesh,

      In general T5 tubelight gives more brightness per watt of energy. You can even use a 2 Ft T5 tubelight which is 14 watt if you want to illuminate the whole room (based on the size of room). Smaller wattages can be used if you use table lamps while working. It will depend on what is comfortable for you.

  5. Rahul says:

    Hi,

    The above article is very helpful. However now i am a bit confussed. Let me tell you the history.
    In my flat the living room size is 17 feet x 11 feet. I have made a false ceiling in the room and have also made provision for LED STRIP which will run to about 40 feet in rectangle shape in the room. I have also made 6 holes of 7 inch x 7 inch for the light fittings. I was planning to install CFLs as people told me it saves electricity. (But frankly i am not very satisfied with the CFL light as it looks very dim compared to our traditional TUBE LIGHT.)

    My Queries.
    1. How much lumens light is required for such room.
    2. If i have to install LED Fittings, then how many LED fittings and of what Wattage should be installed.
    3. If I have to istall CFL, then how many and of what wattage should be installed.
    3. How much would I save if i install TUBE LIGHT or CFL or LED fitting

    Thanks,
    Rahul.

    • abhishekjain203 says:

      Hi Rahul,

      A 17 feet by 11 feet room would need about 4500 lumens in total. Which can be achieved by putting 2 tubelights (best option is slim T5 tubelights of 28 W each). Or if you want to put 6 CFLs then 6 CFLs of 15 – 18 W each would work. Certainly if you put all the lights “on” then 2 T5 tubelights would be more economical as it will just consume 56 Watts in total. But if you put 6 CFLs then it can be more controlled in such a way that you can put one switch for 2 CFLs and when required you put on only 2 or 4 or all 6. But that will be beneficial only if you feel that you are working in particular area of the room and lighting only that portion is sufficient. So CFLs will give you more control and saving in case you do not want the whole room to be lighted. But if you like the whole room to be lit well, then I would suggest you to go for energy efficient T5 tubelights (2 of them). Cost wise both the options may turn out to be same but you will save 6 units a month (if used for 6 hours every day) if you use T5 (and use all the lights all the time).

      In case you are thinking of LED, then LED downlighters will be the best. The wattage required will be slightly more than tubelights and it will be much more costlier as well. So the best idea would be to use 2 T5 (energy efficient) tubelights. You just have to be a little creative to use it on a false ceiling so that you do not obstruct the light coming from the tubelights. Using white reflective surfaces can help.

      Regards,
      Abhishek

  6. prasanna says:

    led is nice… but is it possible to get the leds in the size of tubelights?

  7. BHOMA RAM NAI says:

    DESH- DUNIYA KI TARRAKI KE LIYE JO KAAM VAIGYANIKO NE OORJA (BIJLI) BACHANE KE ANEK SADHAN BANAKAR KIYA HAI UNSE BHI BARA KAAM HAM UN SADHNO KA ISTEMAL KARKE KAR SAKTE HAI AGAR PRAKASH KE LIYE SABHI LOG LED LIGHT KA PRAYOG KARNE LAGEN TO BIJLI KI VATMAN SE 80% KHAPAT GHAT JAYEGI YANI BIJLI KI ATAM NIRBHATA………JAI BHARAT BHOMA RAM NAI BAPEU (BIKANER RAJASTHAN SE)

  8. SHER SINGH THAKUR says:

    our one unit saving of power in north can save a life of patient in south who may be on the operation theatre & due to this one unit saving in north grid failure could be avoided in south,am I wrong——THINK-THINK–THINK

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