The surprising key to viable carbon sequestration: build more highways

Many innovations aimed at reducing carbon dioxide have been put forward. Now, a California entrepreneur is proposing a more practical solution

Humanity has been trying to cut down on the estimated 40bn metric tons of carbon dioxide produced each year for decades. Some countries have imposed carbon taxes. Many businesses are looking at using alternatives to fossil fuels to make their products. For example, Coca-Cola invested millions of dollars in creating its PlantBottle, which gets its plastic from plants instead of petroleum, and saved 315,000 metric tons of CO2 between 2009 and 2015.

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