Why I Want My Son to Switch Off the Lights
Why I Want My Son to Switch Off the Lights I am forever telling my son to switch off the lights and the fan when he leaves his room. And like most mothers, I sometimes wonder why I have to say the same thing again and again. So I thought I would actually do the maths. If we take a regular ceiling fan of about 75 watts and an LED bulb of about 9 watts, running them for 12 hours instead of 4 hours uses about 20 extra units of electricity every month, or about 245 units over a year. Depending on your electricity tariff, that may amount to only around ₹100 or so a month. Not exactly an amount that is going to change our lives. There is, of course, an environmental cost too. If that same fan and light were left on for 24 hours a day instead of, say, 9 hours, they would use about 460 extra units of electricity over a year. Using the average carbon footprint of electricity supplied by the Indian grid, that works out to roughly 330 kg of additional CO₂ emissions in a year . So yes, there...