LED - Power saver

P Jadumani Singh *

R, G, and B LEDs :: Pix - Wikipedia/PiccoloNamek

EARTH HOUR, launched in Sydney in 2007, is a largest environmental campaign in the history of our planet with a message to every individual of the world to switch off non-essential lights for one hour on the last Saturday of every March between 8.30 and 9.30 pm. It is an awareness campaign for energy conservation and for action on climate change. This worldwide movement is organised by the World Wide Fund for Nature (WWF).

The Indian prime minister, Sri Narendra Modi launched a national programme called "Prakash Path" meaning "way to light" on 5th January 2015 for energy conservation. In this campaign LED bulbs only are selected for use in the domestic and street lightings, ignoring other incandescent, fluorescent, halogen bulbs etc.

On this day the prime minister replaced all the existing incandescent, fluorescent bulbs of his office with LED (light emitting diode) lamps. The entire project of installing LED bulbs for domestic and street lightings is targeted for completion by March 2016 in 100 cities and with a policy of subsidising the rate for this lamp at Rs. 130/- per bulb whereas in the open market the retail price is in the range of Rs. 350-600.

Some years before, incandescent bulbs have been slowly phased out by introducing the fluorescent lamps for consuming less electric power with more lumens (amount of light, more lumens means brighter light, fewer lumens gives dim light).

The United States of America has already adopted the use of LED and fluorescent lamps some fifty years ago. Fossil fuels like the coal, oil, natural gases etc, which are formed in the earth depth by natural process such as anaerobic decomposition of dead organisms, are non-renewable energy sources and one day these will be exhausted.

The water level for generation of hydro power will slowly be lowered due to climate and ecological changes. Of course, solar power will be alternative and perennial source for human use in any aspect, although it cannot reach the scale of generation from the fuel fossils, water etc for the time being. LED bulb is power saving lamp although the initial cost is more. It consumes less power and gives more light.

In the domestic and street lightings, the energy consumption by CFL and LED bulbs will be reduced by 3/4th of the present quantum of power supplied by the Manipur government. LED bulbs face competition from the compact fluorescent lamps, which are almost as energy efficient and cost less. United States has ceased the production of 100 watt bulbs and Europe has stopped manufacturing 60 watt lamps.

From 2014, U.S. has banned the marketing of incandescent lamps of 40 watt and above. If the system of power saving is properly introduced in Manipur by ordinancing the use of LED bulbs in all households and street lights, our government will have to incur lesser amount in the purchase of power from the outside with no load shedding.

Providing of pre-paid meters, use of LED bulbs and disconnection of un-authorised consumers are some important ways to power saving in Manipur. In the remote and hill villages there are no switches in almost all the houses, because of which the bulbs/fans remain burning/swirling as long as the power supply remains there. Awareness programme of power saving is required to be rendered to these ignorant people. In the 4.57 lakh households in Manipur, the lawful and illegal consumers are respectively 2.30 lakh and 1.50 lakh as per report published some time before.

LED (light emitting diode) is a semi-conductor device that emits light when an electric current passes through it. Diodes are made of very thin layers of semi-conductor materials, one layer of which will have an excess of electrons while the next will have deficit of electrons. This difference causes electrons move from one layer to another, thereby generating/emitting light.

These semi-conductors used for the LED manufacture are gallium arsenide, gallium phosphide or gallium arsenide phosphide. Compact fluorescent lamp is mini version of a standard fluorescent light bulb without any adaptor. A fluorescent lamp or tube is a low pressure mercury vapour gas – discharge bulb. An electric current in the gas excites the mercury vapour which produces short-wave ultraviolet light that causes a phosphor coating on the inside of the bulb to glow.

The luminous capacity of a fluorescent lamp is much more than the efficacy of an incandescent bulb on the same power input, although it is more costly than the latter. Incandescent lamp is a light producing product that uses electricity to heat a wire filament, inside a glass shell that is evacuated or filled up with an enert gas, until it is hot enough to glow white. It was invented by Thomas Edison in 1879.

Governments around the world have passed measures to phase out incandescent lamps in favour of more energy efficient alternatives like LED, CFL etc. The following chart of comparision between the three lamps is furnished for information of the general public:

COMPARISION CHART

Item of comparision Light Emitting Incandescent Compact Fluorescent
Diode (LEDs) Light Bulbs Lamps (CFLs)
1. Life span 50,000 hours 1,200 hours 8,000 hours
2. Light output
i) 450 lumens 4-5 watts 40 watts 9-13 watts
ii) 1,100 lumens 16-20 watts 100 watts 23-30 watts
3. Kilowatt hour generated 329 Kwh/yr 3285 Kwh/yr 767 Kwh/yr

In equal duration of lighting

4. Annual operating cost Rs. 1,478/yr Rs.14, 486/yr Rs.3,449/yr
5. Heat emitted 3.4 btu's/hr 85 btu's/hr 30 btu's/hr

"Save, electricity, save the planet and save your money" should be the policy of every individual.

Our monthly electric bill will be minimum if we use LED, CFL etc which consume 20 to 50 percent of the incandescent bulbs.

Reduction of energy consumption, prevention of energy loss and attending to programs on energy saving technologies are some ways to save energy in our homes.

Lastly eco-friendly energy generated from the renewable sources rather than from the polluting fossil fuels, should be used.