Solar Impulse has demonstrated that a solar-powered airplane can fly day and night using no fuel. The Swiss team's ultimate challenge is to fly around the world. This attempt is scheduled for 2014.

Solar Impulse has a wingspan of 64 m and is powered by 12 000 solar cells. The aircraft is constructed around a skeleton of carbon fibre/honeycomb composites in a sandwich assembly. The upper wing surface is covered with a skin of encapsulated solar cells and the underside with lightweight flexible film. Between these two surfaces, 120 carbon fibre ribs at 50 cm intervals profile these two layers and give the wing its aerodynamic shape.

The aircraft uses technical expertise, polymer materials and energy-saving lightweight materials from Bayer MaterialScience.

The 48-hour, 2500 km journey from Switzerland to Africa will cross the Pyrenees and the Mediterranean and end in Morocco. It follows successful test flights, including Solar Impulse’s first international flight, from Switzerland to France and Belgium, in 2011.

The Solar Impulse project originators Bertrand Piccard and André Borschberg will take turns to fly the aircraft, with a scheduled intermediate stopover near Madrid, Spain, to change pilots.

The trip will coincide with the start of work in Morocco’s Ouarzazate region to construct the largest solar power plant ever built. The Moroccan Agency for Solar Energy (MASEN) will welcome Piccard and Borschberg after the landing. MASEN is leading the implementation of the integrated Moroccan Solar Plan, which aims at developing a minimum power capacity of 2000 MW by 2020.

Leverkusen, Germany, based company Bayer MaterialScience became an Official Partner of the Solar Impulse project in 2010. Since then, researchers at the company’s laboratories in Leverkusen, Dormagen and Krefeld-Uerdingen have been working on ideas for lightweight construction and energy efficiency.