What are the biggest solar planes?

The largest solar-powered aircraft built to date is the Solar Impulse 2. It has a wingspan of 72 meters (236 feet), which is wider than a Boeing 747, and weighs about 2,300 kg (5,000 lbs). Another big one is the Helios Prototype, built by AeroVironment for NASA, with a wingspan of 141 ft (43m) and weight of 1,500 lb (680 kg).

Other notable large solar-powered aircraft include:

Zephyr:

This drone, built by Airbus Defence and Space, has a wingspan of 25 meters (82 feet) and can fly for several weeks at a time at an altitude of 70,000 feet.

SolarStratos:

Developed by the Swiss company SolarStratos, this aircraft has a wingspan of 23.5 meters (77 feet) and is specifically designed for stratospheric flight, with the goal of reaching an altitude of 30,000 meters (98,000 feet).

Sunseeker Duo:

Developed by the University of California, San Diego, this aircraft has a wingspan of 32.4 meters (106.3 feet) and set a world record for the longest solar-powered flight by a manned aircraft in 2011, flying for over 18 hours.

SolarEagle:

Developed by Boeing Phantom Works for the U.S. military, SolarEagle was designed to fly at high altitude for up to five years continuously to provide persistent surveillance. The project was cancelled after the prototype.