Google's plan to beam the internet down from hot air balloons might sound like something out of a futuristic children's book, but it's moving closer to reality.

Project Loon, part of Google parent company Alphabet's "moonshots" division, has been under way since 2013, with its team mostly developing the project in secret and occasionally running unannounced tests. Now, Loon says it has had a breakthrough that could bring that to fruition sooner than initially expected.

Originally, the plan called for the balloons to traverse the globe, beaming down internet as they floated along. But by improving the company's artificial intelligence software, Loon engineers have found a way to keep the balloons bundled within certain areas. This will allow the company to use far fewer balloons, making the project less expensive, according to Recode.

Specifically, the Loon team made changes to the software that controls the balloons' altitude and navigation. An area that would have needed 200 or 300 balloons to get internet will now require as few as 10 or 20, since they'll be able to hover in the locations in need of signal instead of also drifting over places where they're not needed.

"We've actually made so much progress that we think our timeline for when we can provide useful internet service to people is much, much sooner," Loon engineer Sal Candido said at an event at Google's Mountain View headquarters on Thursday, according to Recode. It's still not clear how soon that might be, or how much the breakthrough might save the company in costs.

Last year, Alphabet began cutting back on spending for some of its riskier long-term bets. Google Fiber, the project to deliver high-speed broadband in cities throughout the U.S., halted its expansion indefinitely in October. And in December, the company abandoned its plans to develop its own self-driving car, deciding instead to work on software that could be used in partnership with existing automakers. Alphabet's "Other Bets" division, which houses the moonshot unit known as X, has consistently lost upwards of $800 million per quarter throughout the past several years.

With Loon, the company says its cost-saving measure moves it closer to becoming a sustainable business. "The service has a much better chance of ultimately being profitable," said Astro Teller, the head of Alphabet's moonshot unit, according to Bloomberg.

Other companies are trying to capitalize on the 4.5 billion people--more than half the world's population--who still lack internet access. Since installing broadband cables likely wouldn't be a profitable venture in sparsely populated areas, companies are trying alternative methods. Facebook has run several test flights of Aquila, a drone with a wingspan wider than that of a 737, though one of those flights resulted in a crash landing in the Arizona desert in December. SpaceX asked the FCC for permission to create a constellation of satellites that can beam internet to the earth. In recent months, the company has posted more than 60 job openings in Washington State, where its internet project is headquartered.

Like Facebook, Google has a lot to gain by bringing the internet to more people's fingertips, since that would translate into more advertising dollars.

In September, a Project Loon test balloon was spotted over Yellowstone National Park--an area usually devoid of internet connectivity. Most of Loon's testing has occurred in South America, according to the company.