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  • In a world exhausted of fossil fuels,

  • solar panels can provide a sustainable solution to our energy problems.

  • But they also come with a couple of issues:

  • for one, solar farms are massive,

  • and they have to be set up somewhere that gets a lot of sunlight.

  • Now, if only we had a large mass of unused land

  • that gets guaranteed sunlight everyday... hmm...

  • This is WHAT IF, and here's what would happen

  • if we covered the Sahara desert with solar panels.

  • If we covered just 1.2 percent of the Sahara desert in solar panels,

  • we could harness enough power to meet the energy needs of the entire world.

  • Usually, a solar farm is built to prevent changes to the environment,

  • but if we built one in the Sahara, it might cause some changes of its own.

  • If we lined the desert floor with giant solar panels,

  • it would double the rainfall in the region

  • and increase vegetation cover by about 20 percent.

  • Sound a little unbelievable? Well, let me explain.

  • Saharan sand is unusually light in color,

  • which means it tends to reflect a lot of light and heat back up into the air.

  • If we covered the sand in dark solar panels,

  • it would mean that more sun would be absorbed,

  • and the ground temperature would increase.

  • Warmer air rises to areas in the atmosphere where it's cooler,

  • and moisture there condenses and falls as rain.

  • Before you knew it, one of the most extreme climates on Earth

  • would undergo a significant makeover.

  • So if these solar panels would not only provide sustainable energy solutions,

  • but also add much-needed greenery to our largest desert, then what are we waiting for?

  • Shouldn't we be out there building these things already?

  • Well, it's a little more complicated than that.

  • For one thing, it's great to produce enough energy to power the world,

  • but then you have to worry about how you're going to get it to everyone.

  • The most likely place this energy would travel to first is to Europe.

  • Exporting sustainable energy would do great things for a lot of African economies,

  • but would they have the means to do it?

  • Currently, electrical grids in Africa aren't very reliable,

  • and they'd need power lines of around 800 - 3,000 km (500 to 2,000 miles)

  • to get where they needed to go.

  • Transporting power over long distances leads to power loss of up to 10%,

  • which means that an already expensive project would get even more pricey.

  • And where would all the money come from?

  • Africa is home to quite a few unstable governments,

  • the kind that raise some pretty big red flags

  • with investors of multi-billion dollar projects like this one.

  • On top of that, this would be a long-term project, so there'd be a lot of moving parts.

  • Several countries would have to be involved,

  • and any one of them might see a changing political landscape over the years

  • that could disrupt, or put an end to the whole thing.

  • As great as this project would be,

  • it would probably be better to attempt it on a small scale first.

  • Maybe solar panels could be used to power some small African villages,

  • and help to spread access to electricity,

  • but that's a topic for another WHAT IF.

In a world exhausted of fossil fuels,

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如果撒哈拉沙漠被太陽能電池板覆蓋會怎樣? (What If the Sahara Desert Was Covered With Solar Panels?)

  • 13 1
    林宜悉 發佈於 2021 年 01 月 14 日
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