Project Loon, Google’s project to use balloons to bring Internet access to underserved parts of the world, could bring in billions of dollars, according to a report in The Verge.

Google VP and Project Loon lead Mike Cassidy sees it like this: if the balloons bring Internet access to just 5% of the 4.5 billion people currently without it— and Google gets $5 a month from each user—that would mean tens of billions in revenue for the company.

Of course, Cassidy’s figure doesn’t factor in the costs of running the ballon-based Internet system, which could be high. And since most of the underserved parts of the world are in developing areas, $5 a month is a lot to charge.

Project Loon began as an experimental project for the company about four years ago. Google is currently testing the Internet-beaming balloons in New Zealand, with ambitions to expand the project to other parts of the world.

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