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The inventors, entrepreneurs and disrupters who are changing (and maybe saving) the world one brilliant idea at a time

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Alex Steffen: Build Up, Not Out
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Courtesy of Alex Steffen12/25

Alex Steffen: Build Up, Not Out

Alex Steffen, the author of Carbon Zero, thinks crowded megacities could be the ideal frontier for fighting climate change. As cities get denser, their per-capita energy costs drop. By 2050, he envisions humanity scattered among a constellation of walkable urban centers, powered by decentralized green energy, with a largely car-free population living in eco-friendly housing. At a certain point, he says, "people buy efficient and sustainable buildings just because they work better." In the next decade, he foresees a "snap forward," the "start of an inevitable process of the zero-carbon future out-competing the high-carbon future." The worst mistake we can make "is to think the world of the next 10 years will be like the world of the last 10," Steffen says. The decisions we make now will be "the difference between a planet with serious climate challenges but a bright future and one working with catastrophe." SE

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