As of 2015, with current technology, solar-powered airplanes are not viable for commercial use. The main reasons are that they travel too slow and are not able to carry a large number of people.
The Solar Impulse 2 is an experimental solar-powered airplane that hopes to be the first plane to circle the planet without using fossil fuels. While it has proven that it can handle long-range flights, the plane has several significant disadvantages, including a top speed of 43 miles per hour and a maximum capacity of two people. As typical commercial airplanes like the Boeing 747 can reach speeds of 570 miles per hour and carry over 400 people, solar-powered airplanes are still far from being viable for commercial use.