Energy Efficient Lighting

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How much light do you really need for your room? The unit of light is lumens.
Learn to think of light in lumens not Watts.

For household lighting, 15 lm/ft2 is more than enough.
For offices, use 30 lm/ft2.
For factories, use 50 lm/ft2.

Calculate your total lumens requirements using these numbers.

Divide your total requirement by the lumens given next to each option in the table below, to calculate how many tubelights or bulbs you need. Compare CFL vs LED, as well as LFL tubelights and the old incandescent bulbs. 

The main indicator you should look at is the Efficacy of the lighting option, which shows how many lumens you get per Watt of electricity consumed. The higher the efficacy, the more energy efficient the light bulb is.

The electricity used and annual bill results shown below make the following assumptions: It is a 3BDR/3BTH house. The electricity tariff is Rs.10 + tax (tariff for Pakistani residential consumers using 200-300 units per month). For commercial users, and residential users with higher bills, the difference in lifecycle costs will be even higher.

As you can see in the table below, LEDs have finally come into their own. The Philips Bright Boost 36W tubelight is still the best in terms of price and efficacy combination. However, considering that LEDS offer directed light, in most cases the efficacy of LEDs can be considered almost double of their nameplate values. This is because LEDS direct light to where it is needed, whereas incadescent bulbs, CFL (energy savers) and LFL tubelights diffuse light in all directions. LEDs are also good options if you plan to use a solar system to power your house or office, since solar systems provide DC power, which is what LEDs use. Otherwise, solar systems lose up tp 25% power converting from DC to AC. (As a disclaimer, most solar installations convert to AC in any case, so that they have one wiring system for all appliances, lights, etc in the house.)

Brand Series Type Colour Power reqd Market price Efficacy Lumens Lifetime Fixtures Reqd Electricity/day Electricity/year Annual Electricity bill Lifecycle Cost
      (W) (Rs) (lm/W)   (Hours)   (kWh) (kWh) (Rs) (Rs)
Philips Bright Boost Super 80 T5 Tubelight Cool Daylight 36 150 90 3,250 15,000 7 0.77 280 3,274 33,805
Osaka Tubelight - 4 feet LED DL/WW 18 800 111 2,000   12 0.62 227 2,652 35,720
Opple   LED   8   75 600 25000 38 0.92 336 3,929 39,289
Osaka A60 - Bulb LED DL/WW 12.5 500 96 1,200   19 0.72 262 3,069 40,278
Osaka A60 - Bulb LED DL/WW 7.5 325 96 720   32 0.72 262 3,069 41,076
Osaka A60 - Bulb LED DL/WW 9.5 400 95 900   26 0.73 266 3,110 41,326
Philips Bright Boost Super 80 T5 Tubelight Cool Daylight 18 137 75 1,350 15,000 17 0.92 336 3,929 41,623
Philips Lifemax Tl-D T5 Tubelight Cool Daylight 36 109 72 2,600 15,000 9 0.96 350 4,093 41,893
Osaka A60 - Bulb LED DL/WW 5.5 270 96 530   43 0.72 261 3,058 42,295
Osaka Tubelight - 2feet LED DL/WW 9 700 111 1,000   23 0.62 227 2,652 42,620
Osaka A60 - Bulb LED DL/WW 3.5 200 94 330   70 0.73 267 3,125 45,192
Philips round bulb LED Cool Daylight 9 449 89.55556 806 15000 29 0.77 281 3,290 45,716
Osaka T9 T9 Tubelight Cool Daylight 40 55 65 2,600   9 1.06 387 4,533 45,820
Osaka round bulb LED DL 70 2,300 80 5,600   4 0.86 315 3,683 46,279
Osaka round bulb LED DL 50 1,750 80 4,000   6 0.86 315 3,683 46,896
Osaka round bulb LED DL 35 1,350 80 2,800   8 0.86 315 3,683 47,922
Tuff (Osaka) SP CFL Cool Daylight 25 93 65 1,625   14 1.06 387 4,533 47,966
Philips Tornado CFL Warm White 23 219 70 1,550 8,000 14 0.99 360 4,209 48,352
Osaka round bulb LED DL 30 1,300 80 2,400   10 0.86 315 3,683 49,291
Tuff (Osaka) SP CFL Cool Daylight 25 140 65 1,625   14 1.06 387 4,533 49,296
Philips round bulb LED Cool Daylight 7 399 85.71429 600 15000 38 0.81 294 3,438 49,673
Yamao round bulb LED Cool Daylight 10 499 81 810 25,000 28 0.85 311 3,638 50,547
Philips Tornado  CFL Cool Daylight 23 195 66 1,450 8,000 15 1.05 382 4,465 50,555
Osaka round bulb LED DL 25 1,250 80 2,000 12 0.86 315 3,683 51,208
Osaka round bulb LED DL 24 1,250 80 1,920 12 0.86 315 3,683 51,807
Philips Essential  CFL Cool Daylight 18 185 65 1,170 8,000 20 1.06 387 4,533 52,607
Osaka round bulb LED DL 18 1,000 80 1,440 16 0.86 315 3,683 52,805
Philips round bulb LED Cool Daylight 4 299 87.5 350 15000 66 0.79 288 3,368 53,325
Tuff (Osaka) SP CFL Cool Daylight 11 125 65 715 32 1.06 387 4,533 53,375
Philips Lifemax T5 Tubelight Cool Daylight 18 98 57 1,030 15,000 22 1.21 442 5,170 53,892
Yamao round bulb LED Cool Daylight 5 299 80 400 25,000 58 0.86 315 3,683 54,026
Osaka Downlight- MR16 LED WW 5 300 80 400 58 0.86 315 3,683 54,083
Philips Decotwist  CFL Cool Daylight 25 400 68 1,700 14 1.01 370 4,333 54,157
Philips Tornado  CFL Cool Daylight 24 229 62.5 1,500 8,000 15 1.10 403 4,715 54,169
Philips Essential  CFL Warm White 18 185 61 1,100 8,000 21 1.13 413 4,831 56,056
Tuff (Osaka) SP CFL Cool Daylight 8 125 65 520 44 1.06 387 4,533 56,391
Philips Genie  CFL Warm White 18 200 61 1,100 8,000 21 1.13 413 4,831 56,685
Philips Ecotone  CFL Cool Daylight 80 1459 66.25 5300 4 1.04 380 4,448 57,141
Philips Essential  CFL Warm White 14 165 61 850 8,000 27 1.14 415 4,853 57,462
Osaka SP CFL Cool Daylight 30 219 56 1,680 14 1.23 450 5,262 58,615
Osaka Lotus CFL Warm White 85 1,099 60 5,100 5 1.15 420 4,911 59,023
Osaka 3U CFL Cool Daylight 20 165 56 1,100 21 1.23 450 5,262 59,395
Philips Genie  CFL Cool Daylight 18 200 58 1,040 8,000 22 1.19 434 5,080 59,616
Philips Essential  CFL Cool Daylight 14 165 58 810 8,000 28 1.19 435 5,093 60,300
Osaka 3U CFL Cool Daylight 11 165 60 650 35 1.15 420 4,911 60,611
Philips Ecotone  CFL Cool Daylight 65 1,159 61 4,000 6 1.13 413 4,831 61,752
Philips Ecotone  CFL Cool Daylight 45 1029 63.33333 2850 8 1.09 398 4,653 63,134
Yamao round bulb LED Cool Daylight 7 399 67 470 25,000 49 1.03 375 4,389 63,412
LED 7 649 78.57143 550 25000 42 0.88 321 3,750 64,643
Osaka Panel 2'x2' LED DL/WW 40 4,000 80 3,200 30,000 7 0.86 315 3,683 65,583
Osaka Downlight- MR16 LED WW 8 420 63 500 46 1.10 403 4,715 66,466
Crest round bulb LED Cool Daylight 7 1,399 112 784 29 0.62 225 2,631 67,351
Crest round bulb LED Cool Daylight 3 619 112 336 68 0.62 225 2,631 68,681
Philips Genie  CFL Cool Daylight 11 200 54 600 8,000 39 1.28 466 5,457 70,056
Philips Genie  CFL Warm White 11 200 54 600 8,000 39 1.28 466 5,457 70,056
Crest round bulb LED Cool Daylight 5 1,079 112 560 41 0.62 225 2,631 70,625
Philips Genie  CFL Warm White 8 200 55 610 8,000 52 1.25 458 5,358 74,484
Philips Ambiance  CFL Warm White 23 650 54 1,250 8,000 19 1.28 466 5,457 78,642
Philips Genie  CFL Cool Daylight 8 200 52 415 8,000 55 1.33 484 5,667 78,782
Osaka Globe CFL Cool Daylight 20 289 45 900 26 1.53 560 6,548 80,252
Osaka C37- Candle bulb LED WW 5 250 50 250 50,000 92 1.38 504 5,893 81,933
Philips Genie  CFL Warm White 5 200 50 250 8,000 92 1.38 504 5,893 95,733
Osaka Panel 1'x4' LED DL/WW 42 8,000 76 3,200 30,000 7 0.91 331 3,867 96,175
Osaka Panel 2'x2' LED DL/WW 42 8,000 76 3,200 30,000 7 0.91 331 3,867 96,175
Philips Genie  CFL Cool Daylight 5 200 47 235 8,000 98 1.47 536 6,269 101,844
incandescent all models & brands incandescent Warm White 100 30 12 1200 1000-2000 19 5.75 2,099 24,555 251,304