It seems kind of obvious when you think about it: why not just stick a solar panel on a quadcopter so it can fly on solar power? Unfortunately, physics is a cruel mistress, and it gets a bit more complex when you look at problems like weight to power ratios, panel efficiency, and similar tedious technical details. This group of National University of Singapore students has gone some way to overcome these technical issues, though: they just built a drone that is powered from solar power alone, with no batteries or other power source.
Their creation is a custom-built quadcopter made with carbon fiber that weighs just 2.6kg (about 5.7lbs), but which has about 4 square meters (about 43 square feet) of solar panels. By testing and hand-selecting the panels with the best efficiency, they were able to generate enough power to drive the four rotors, and have managed to achieve altitudes of up to 10 meters. The students have been working on prototypes of this since 2012, when their first version could only generate 45% of the power needed for flight. So, reaching 100% of flight power in the demo shown below is a significant step.
This prototype does look a bit rickety, though: all of that solar panel surface acts as a sail and will catch the wind, so we doubt it will be stable in anything more than a slight breeze. But we’re sure the future holds improvements.