Google is planning to use hot-air balloons to provide WIFI hotspots.

Google's "Project Loon" is a project that uses balloons as WIFI hotspots to provide internet services to the ground. The balloons are made of polyethylene plastic, with a diameter of 15 meters, and the entire device is 12 meters high, powered by solar panels. They fly in the stratosphere, 20 kilometers above the ground, and cannot be seen with the naked eye.

Google conducted a test where signal transmission and reception equipment was installed on 30 test balloons, and these devices could connect with ground receivers. After testing, it was found that when the ground equipment connected to the WIFI signal from the balloons, the internet speed was comparable to 3G, and sometimes even exceeded the level of 3G.

The balloon internet project is one of the projects under Google X, which is Google's laboratory mainly focusing on future large "moonshot" projects. Projects like Google Glass and self-driving cars are also under Google X.