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  • Decarbonization.

  • It's a key factor in the fight against climate change.

  • The goal is simple, to reduce carbon dioxide emissions

  • around the world as soon as possible.

  • Our planet can not be saved unless we leave fossil fuels

  • in the ground where they belong.

  • Decarbonization requires

  • both sweeping change and incremental steps,

  • working industry by industry, process by process,

  • in every major country in the world.

  • Sound expensive?

  • It will be.

  • But the science community agrees

  • that to avoid global catastrophe,

  • we have no choice but to mobilize and take on

  • this monumental challenge. What do we want?

  • Climate justice!

  • When do we want it? Now!

  • Renewable energy, like wind turbines

  • and solar panels, as well as electric cars,

  • are the more popular topics in the conversation.

  • But there are other key sectors that are less-discussed,

  • and changes there are equally important

  • for decarbonizing the planet.

  • Here's three.

  • Cement, steel, and agriculture.

  • These three sectors combined

  • make up almost 40% of all carbon emissions in the world.

  • What will it take to revolutionize

  • these three industries without bankrupting them?

  • Cement is the most widley-used

  • manmade material in existence.

  • When combined with water and aggregates,

  • it can be poured into whatever shape

  • is needed for construction.

  • Cement has been used for millennia,

  • to build structures like the Pantheon and Roman aqueducts,

  • to highways and parking garages.

  • Lots of parking garages.

  • Globally, the production of cement

  • accounts of 7% of yearly CO2 emissions.

  • And that's largely because of how cement is created.

  • The main ingredient to cement is a substance called clinker.

  • In order to produce this,

  • limestone is heated to high temperatures.

  • And usually, this heat is generated

  • by fossil fuels, releasing CO2.

  • Meanwhile, the chemical reactions inside the kiln

  • release even more CO2 in the process.

  • Companies are working to reduce the amount of clinker used.

  • Others are testing substitutes, including fly ash,

  • which is the residue left in chimneys

  • of coal-burning furnaces, or slag from iron production.

  • But the drawbacks are serious.

  • These new techniques come with a price tag

  • sometimes triple the cost of the traditional process.

  • And since cement is holding many

  • of the world's structures together,

  • alternative recipes make contractors and regulators uneasy.

  • Steel is just as important as cement,

  • and as cities grow, global demand

  • is expected to rise by 50% between 2019 and 2050.

  • But its process involves purifying iron ore

  • in blast furnaces, with a refined form of coal called coke.

  • And just like cement, this production produces a lot of CO2.

  • In Europe, blast furnace owners

  • are testing hydrogen as an alternative way

  • to take the carbon out of iron ore.

  • But again, so far, it's way too expensive to go mainstream.

  • About double the cost of using coke.

  • There's one thing you can do with steel

  • that you can't do with cement.

  • And that is recycle.

  • Instead of producing more steel in the first place,

  • we can use what we already have.

  • Increasing the use of steel recycling is now commonly seen

  • as critical to reducing carbon emissions.

  • Now agriculture requires a multi-pronged effort,

  • as it is responsible for nearly 25%

  • of global CO2 emissions.

  • The practice of controlled burns after harvests,

  • the use of inorganic fertilizers

  • that release methane and nitrous oxide into the air,

  • the destruction of rainforests for ranching,

  • and even livestock flatulence, all need to be addressed

  • to put a dent in agriculture's carbon output.

  • Some hope can be seen in the US,

  • as demands for beef products have dropped significantly.

  • Additionally, interest in alternatives,

  • like Beyond Meat and Impossible Burgers,

  • have soared in recent years.

  • And for those who can't quit beef,

  • scientists are developing climate-proof cows,

  • with digestive systems that produce less methane.

  • But implementing these solutions globally

  • remains an uphill battle.

  • Even as more people in Europe and the US

  • take up vegetarian alternatives,

  • increased meat demand in China and other developing nations

  • means that globally, animal product consumption

  • is expected to rise 60% by 2050.

  • You are the last best hope of Earth.

  • We are in the beginning of a mass extinction,

  • and all you can talk about is money

  • and fairy tales of eternal economic growth.

  • How dare you.

  • It'll take policy makers and companies

  • years of diligent work and collaboration

  • to move industry away from its most polluting methods.

  • But each of these industries is working on answers,

  • with some executives confident

  • they can be both green and show a profit.

Decarbonization.

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脱炭素化に向けてムーブしている理由 (Why We're Moo-ving Toward Decarbonization)

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    林宜悉 に公開 2021 年 01 月 14 日
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