It makes financial sense to even discard your functioning CFLs and switch to LEDs. You save more money if you do that
There is a lot of talk about light-emitting diode (LED) lighting. The govt. has tried in various ways to popularise this energy efficient and green form of lighting. Even compared to compact fluorescent lamps (CFLs), LEDs are better as they tend to be even more efficient, have longer lives and do not contain harmful mercury. However, universal acceptance has still eluded us.
This is surprising as we are at an inflection point where it actually makes sense to throw away the existing working CFL bulbs and switch to LED bulbs right away. The savings in electricity due to lower units consumed actually pay for the LED bulbs including interest.
Light output typically ranges between 40-60 lumens per watt for CFLs with lower values for lower capacity bulbs. On the other hand, newer LED bulbs are able to achieve 100 lumens per watt across a broad range.
Consider a concrete example. A LED bulb of 10.5W power is equivalent to 100W incandescent bulb or 18W CFL. Assuming usage of 1,000 hours a year (at 2.7 hours a day), LED bulb saves 7.5 units (kilowatt-hour-kWh) a year compared to a CFL. Assuming electricity charge of Rs7 per unit, this saves Rs52.50 a year. A recent price of a new LED bulb of this kind is Rs400. (You may even get it cheaper online)
These financials are compelling. Just the savings in electricity pay for the bulbs. At 10% interest, assuming 15 years (15,000 hrs life) of the LED bulb, the equated monthly instalment (EMI) for Rs400 (the purchase cost) comes to Rs4.30 a month or Rs51.50 per year. This is actually less than the total electricity savings! Moreover, unlike the fixed EMI, the electricity prices will increase over the 15-year lifetime of the bulb, due to inflation.
Now, let’s see calculations for a CFL bulb. A typical CFL bulb lasts about 6 years (6,000-hour life). So including the cost of replacement CFLs and inflation, the notional return on investment (RoI) is about 20% per annum for our Rs400 investment. The case only gets stronger the higher the number of hours a bulb is used per day.
Users of all kinds - residential, commercial and industrial, can make the change straight away. Whether using 1 or 100 every one will benefit. There is no need for CFLs to go bad before shifting to LEDs. This is a rare case where going green also makes financial sense. India as whole suffers from power shortage and a broad acceptance of LED bulbs will help reduce that problem as well.
So lets LEaD !
Please note that the above is correct to the best of the author's knowledge.
(Nemi Jain studied Engineering at IIT Bombay. He has spent a major part of his career working in banks)