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  • No matter how we make electricity, it takes up space.

  • Electricity from coal requires mines, and plants to burn it

  • and convert the heat into electricity.

  • Nuclear power takes uranium mines, facilities to refine the uranium,

  • a reactor, and a place to store the spent fuel safely.

  • Renewable energy needs wind turbines or solar panels.

  • How much space depends on the power source.

  • Say you wanted to power a 10-watt light bulb with fossil fuels like coal.

  • Fossil fuels can produce up to 2,000 watts per square meter,

  • so it would only take a credit card-sized chunk of land to power the light bulb.

  • With nuclear power, you might only need an area

  • about the size of the palms of your hands.

  • With solar power, you'd need at least 0.3 square meters of land

  • twice the size of a cafeteria tray.

  • Wind power would take roughly 7 square meters

  • about half the size of a parking spaceto power the bulb.

  • When you consider the space needed to power cities, countries,

  • and the whole world, it adds up fast.

  • Today, the world uses 3 trillion watts of electricity.

  • To power the entire world with only fossil fuels,

  • you'd need at least about 1,200 square kilometers of space

  • roughly the area of Grand Bahama island.

  • With nuclear energy, you'd need almost four times as much space at a minimum

  • roughly 4,000 square kilometers, a little less than the area of Delaware.

  • With solar, you'd need at least 95,000 square kilometers,

  • approximately the area of South Korea.

  • With wind power, you'd need two millionabout the area of Mexico.

  • For each power source, there's variability in how much power

  • it can generate per square meter,

  • but these numbers give us a general sense of the space needed.

  • Of course, building energy infrastructure in a desert, a rainforest, a town,

  • or even in the ocean are completely different prospects.

  • And energy sources monopolize the space they occupy to very different extents.

  • Take wind power.

  • Wind turbines need to be spread outsometimes half a kilometer apart

  • so that the turbulence from one turbine

  • doesn't reduce the efficiency of the others.

  • So, much of the land needed to generate wind power

  • is still available for other uses.

  • But the baseline amount of space still matters,

  • because cities and other densely populated areas have high electricity demands,

  • and space near them is often limited.

  • Our current power infrastructure works best

  • when electricity is generated where and when it's needed,

  • rather than being stored or sent across long distances.

  • Still, space demands are only part of the equation.

  • As of 2020, 2/3 of our electricity comes from fossil fuels.

  • Every year, electricity generation is responsible for about 27%

  • of the more than 50 billion tons of greenhouse gases

  • we add to the atmosphere,

  • accelerating climate change and all its harms.

  • So although fossil fuels require the least space of our existing technologies,

  • we can't continue to rely on them.

  • Cost is another consideration.

  • Nuclear plants don't emit greenhouse gases and don't require much space,

  • but they're way more expensive to build than solar panels or wind turbines,

  • and have waste to deal with.

  • Renewables have almost no marginal costs

  • unlike with plants powered by fossil fuels,

  • you don't need to keep purchasing fuel to generate electricity.

  • But you do need lots of wind and sunlight,

  • which are more available in some places than others.

  • No single approach will be the best option to power the entire world

  • while eliminating harmful greenhouse gas emissions.

  • For some places, nuclear power might be the best option

  • for replacing fossil fuels.

  • Others, like the U.S., have the natural resources

  • to get most or all of their electricity from renewables.

  • And across the board, we should be working to make our power sources better:

  • safer in the case of nuclear,

  • and easier to store and transport in the case of renewables.

No matter how we make electricity, it takes up space.

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B1 TED-Ed power electricity space fossil wind

How much land does it take to power the world?

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    林宜悉 posted on 2021/03/16
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