Ah! The good old days before electricity. Did we actually have it better before the first power plant started running? What if everyone on Earth tried getting by with all their lights turned off? We would start to challenge with a perfect Earth-hour, sixty minutes of complete darkness, no artificial light allowed. Would we reduce the light pollution enough to be able to see the Milky way in the night sky? How much electricity would we save? Would it help us fight climate change? This is What IF and here’s what would happen if everyone on the planet switched off their lights for an hour. Humanity has spent the last one hundred years increasing our dependence on electricity. Look around, you computer, microwave, fridge, elevator, traffic lights, public transportation… Everything relies on electrical power. Going completely without power even for an hour would be pretty uncomfortable. So, let’s just limit humanity’s light usage. Hit the lights… Let’s begin. On average humanity consumes 62,000 terajoules of electricity per hour!! That’s how energy your gas powered car would need to drive to Pluto and back. Twice!!! One-fifth of all this energy goes towards lighting. That’s a lot of energy and producing it means spilling a lot of carbon-dioxide into the atmosphere. Obviously clean energy from the sun, wind and water don’t effect the CO2 concentration in the air but they only make up one-third of global electricity production. The rest of it releases green-house gas emissions. The thinking here is, if we gave our power plants an hour break, we would significantly reduce those CO2 emissions on a global level. What an easy way to fight climate change together? or is it? Turns out it’s rather complicated. If this world-wide earth hour cut to at night getting by with the light of some cozy candles is not the best idea. Not only are they a 100 times less efficient than your light bulb but guess what, they also emit CO2 . In theory you can even the score by using just one candle for an light bulb you’ve turned off but if you lit up twice as many as candles you’d actually be emitting more CO2 . What if you didn’t light any candles? You might think we’d emit less carbon-dioxide into the air but you would be wondering , Yeah that’s not how power plants work? The coal burning ones would in fact emit less CO2 during the dark hours but then, everyone would turn their lights back on. For power stations this sudden increasing in demand would mean firing up more generators. As a result, they would emit even more CO2 and this extra carbon waste wold start to to trap more heat in our lower atmosphere possibly speeding up climate change and that’s if power plants would be able to cope with such a rapid increase in demand. In a worse case scenario, they would need to perform an emergency shut down, leaving us with no electricity for days. When that happened you would at least get to enjoy a view of the Milky way at night. A view that light pollution prevents one-third of the world’s population from seeing. So may be you shouldn’t plunge yourself back into darkness. There are better ways to fight climate change than turning off all the lights at the same time, for starters you could try replacing all your incandescent light bulbs with compact fluorescent ones or take public transportation ward. What do you do to reduce your carbon-footprint?