Compact fluorescent lamp (CFL)?


What is it and why it helps?
A Compact fluorescent lamp (CFL) is an energy efficient alternative and are much more efficient than incandescent bulbs. A CFL uses only one-fifth as much electricity as an incandescent lamp to provide the same level of illumination. A 15 W and 20 W CFL can replace a 60 W and 100 W incandescent bulbs respectively.

The lighting efficiency in case of CFL, ranges from 45 lumen per watt to 60 lumen per watt. Since an incandescent bulb converts about 95 per cent of electricity into heat and only five per cent is converted into light, it generates only 14 to 16 lumen per watt. In case of Delhi, where the domestic consumers pay Rs. 4.5 per unit of electricity (kilo watt hour -- kWh), a 60 W incandescent bulb burning for 4 hours a day will consume 87.6 kWh in a year, whereas a 15 W CFL in a similar condition will use 21.9 kWh, saving Rs. 296 to a consumer. Similarly, comparison of 20 W CFL and a 100 W incandescent bulb shows that the CFL will consume 116.8 kWh less saving Rs. 526. Not only savings, CFLs also save heat trapping carbon dioxide emissions. While a 60 W incandescent bulb emits 65 g/hr of CO2, a 15 W CFL emits only 16 g/hr. 

What is the life span and cost?

CFLs last up to six times longer than incandescent bulbs. The average cost of a CFL is in the range of Rs. 80 to 100 compared to Rs. 10 to 15 for an incandescent bulb. Although these cost a bit more than incandescent bulbs, the excess investment is easily paid back in a year’s time.

Where can you get it?

A consumer can buy a CFL from any electrical shop. One can get CFLs manufactured by companies such as Osram and Phillips. There are other manufacturers as well. In addition, low cost Chinese CFLs are also found. You need to check out on the lamp life.

Any concern?

Mercury, which is a proven neurotoxin, is a small but essential component of CFLs. It allows the bulb to be an efficient light source. It has no substitute but its quantity can be reduced. In developed countries like the US and Europe, CFLs with 1 mg of mercury are available but CFLs sold in India however have 3 milligrammes (mg) to 13 mg mercury. There is however no system of collection and proper disposal of used CFLs to be able to avert the risks of mercury contamination. Now collection system is evolving.

Any official policy?

The ‘Bachat Lamp Yojana’ aims at large scale replacement of incandescent bulbs in households by CFLs. It seeks to provide CFLs to households at the price similar to that of incandescent bulbs and plans to utilize the Clean Development Mechanism (CDM) of the Kyoto Protocol to recover the cost differential between the market price of the CFLs and the price at which they are sold to households.  Under this scheme, the Bureau of Energy Efficiency (BEE) is coordinating voluntary efforts to provide high quality CFLs to domestic consumers for about Rs. 15 per lamp, at a rate comparable to that of incandescent bulbs. This would remove the barrier of high CFL price (which is currently Rs. 80 to 100 per lamp) which is constraining its penetration into households. The BEE targets replacement of about 400 million incandescent bulbs in use in the country, leading to a possible reduction of about 6,000 MW of electricity demand, and a reduction of about 24 million tones of CO2 emissions every year