Because CO2 lingers in the atmosphere for more than a century, reducing emissions means only that less gas is being added to the existing problem. Research by James Hansen shows that reducing global CO2 levels requires both a drastic cut in emissions and some way of pulling CO2 from the atmosphere and storing it. Graphic: IEEE Spectrum

By Ross Koningstein & David Fork
18 November 2014 (IEEE Spectrum) – Google cofounder Larry Page is fond of saying that if you choose a harder problem to tackle, you’ll have less competition. This business philosophy has clearly worked out well for the company and led to some remarkably successful “moon shot” projects: a translation engine that knows 80 languages, self-driving cars, and the wearable computer system Google Glass, to name just a few. Starting in 2007, Google committed significant resources to tackle the world’s climate and energy problems. A few of these efforts proved very successful: Google deployed some of the mostenergy-efficient data centers in the world, purchased large amounts of renewable energy, and offset what remained ofits carbon footprint. Google’s boldest energy move was an effort known asRE<C, which aimed to develop renewable energy sources that would generate electricity more cheaply than coal-fired power plants do. The company announced that Google would help promising technologies mature by investing in start-ups and conducting its own internal R&D. Its aspirational goal: to produce a gigawatt of renewable power more cheaply than a coal-fired plant could, and to achieve this in years, not decades. Unfortunately, not every Google moon shot leaves Earth orbit. In 2011, the company decided that RE<C was not on track to meet its target and shut down the initiative. The two of us, who worked as engineers on the internal RE<C projects, were then forced to reexamine our assumptions. At the start of RE<C, we had shared the attitude of many stalwart environmentalists: We felt that with steady improvements to today’s renewable energy technologies, our society could stave off catastrophic climate change. We now know that to be a false hope—but that doesn’t mean the planet is doomed. [more]

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