How Microsoft’s new carbon-negative plan will test the idea of a climate economy

Microsoft shook up the debate about global warming last week by vowing to make its operations carbon negative — meaning it will take more carbon out of the environment than it emits by 2030, and move rapidly to mop up the equivalent of every bit of carbon it has put into the atmosphere since its founding in 1975. Some of Microsoft’s tricks for reducing its carbon emissions are already familiar — using electricity from renewable sources (electricity production accounts for one-third of U.S. carbon emissions, according to the Energy Information Administration), with Microsoft pledging to use 100% renewable electricity by 2025 topping the list. The company is also pursuing energy conservation measures at its buildings and switching to electric vehicles for use on its office campuses.