Turns out Earth Hour is not a very smart idea to fight climate change.

The good old days before electricity… Did we actually have it better before that first power plant started running?

What if everyone on Earth tried getting by with all their lights turned off? We’d start the challenge with a perfect Earth Hour. 60 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?

Humanity has spent the last 100 years increasing our dependance on electricity. Look around…. your computer, air conditioner, 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 and let’s begin. On average, humanity consumes over 62,000 terajoules of electricity per hour. That’s how much energy your gas powered car would need to drive to Pluto and back, TWICE!

One fifths (20%) of all this energy goes towards lighting. That’s a lot of energy, and producing it means spewing a lot of carbon dioxide into the atmosphere.

Obviously, clean energy from the sun, wind and water don’t affect CO2 concentration in the air. But they only make up one third of global electricity production. The rest of it releases greenhouse gas emissions.

The thinking is, if we gave our power plants an hour break, we’d 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 worldwide Earth Hour caught you at night, getting by with the light of some cozy candles is not the best idea.

Not only are they 100 times less efficient than your light bulb, but guess what? They also emit CO2. In theory, you could even the score by using just one candle for every light bulb you turned off. But if you lit up twice as many 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 in the air. But you’d be wrong again – that’s not how power plants work.

The coal-burning ones would, in fact, emit less CO2 during the dark hour. But then everyone would turn their lights back on. For power stations, this sudden increase in demand would mean firing up more generators.

As a result, they would emit even more CO2! And this extra carbon waste would start to trap more heat in our lower atmosphere, possibly speeding up climate change.

And that’s if power plants were able to cope with such a rapid increase in demand. In a worst-case scenario, they’d perform an emergency shutdown, 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 maybe 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, try replacing all your incandescent light bulbs with compact fluorescent ones. Or take public transportation more.

What do you do to reduce your carbon footprint?

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