Sudipta Saha - My Blog

A few days back, I visited a website named www.onebillionbulbs.com. There they have a calculator that can give estimates of how much money and carbondioxide we can save by changing light bulbs. Using that I found out that changing a 60W indascent light-bulb, used 8 hours a day, saves 79 kgs of CO2 from being emitted, annually.

I took this as a base figure. Then I randomly selected some people from my friend’s list and saw the number of friends they had. Seeing wide variations, I assumed that one could have 150 friends. If this person, through his status in facebook, and through other methods could convince some of his friends to change the light bulbs, it would help a lot.

I assumed that 50% of the friends would change 3 60W light bulbs that run 8 hours a day with energy-saving ones. Each would save 79X3 = 237 kgs anually. Therefore 75 of them would save 237X75=17,775 kgs.

If the people who change their light bulbs, in turn tried to convince their friends through facebook, it would be even better. Considering that these people also have 150 friends, and 50 of them are mutual(i.e. already know about this message), the message will be passed onto 75X100= 7500 new people. If 50% of these take the same action, they will save (7500X50%)X237=888,750 kgs of CO2 anually.

Already, in this model situation, 906, 525 kgs of CO2 has been saved, that is around 907 tonnes.

The site mentioned at first also says that saving 5966 kgs of CO2 amounts to removing 1 car from the roads for a year. So saving 888750 kgs anually means removing around 150 cars from the roads for one year.

And its only the beginning. This cycle can go on and on and on, and save many more kgs of CO2. Plus, we could change all the light bulbs and not just three. Its not that we will be saving the world- not even changing all the light bulbs will do that if people dont act in other ways. But atleast we are doing something. Its much better than doing nothing.