Pioneering solar plane lands in Nanjing

High-tech machine stops over on its quest to become the first airplane powered only by the sun to span the globe

Solar Impulse 2, which may become the world's first fixed-wing aircraft completely sustained by solar power to fly around the world, landed in Nanjing, Jiangsu province, just before midnight on April 21.

The Swiss aircraft had remained in Chongqing in southwestern China for three weeks as a result of volatile springtime weather. Its attempt to span the globe began in the Middle East in March.

The two Swiss pilots were preparing both physically and mentally for the Nanjing-Hawaii trip, the longest leg on their global itinerary.

The plane weighs little more than a family car but its wingspan is as wide as that of the largest passenger airliner. Its wings are covered in some 17,000 solar cells that recharge lithium batteries during the day and power four electric motors that drive the plane's propellers.

When the plane landed in Nanjing, a crowd that included dignitaries, aviation fans, media and the plane's support team broke out in cheers to welcome the plane and its Swiss pilot on the cross-China leg, Bertrand Piccard.

Among them was Jean-Jacques de Dardel, ambassador of Switzerland to China. The ambassador said the arrival of Solar Impulse 2 to Nanjing will increase the connections between the historic Chinese city and Switzerland, and he hoped the pioneering Swiss effort would inspire young people in China.

Solar Impulse 2 was created and is flown by Swiss pilots Piccard and Andre Borschberg, who alternate their piloting duties.

The carbon fiber plane took off from Abu Dhabi in the United Arab Emirates on March 9. The trip from Chongqing to Nanjing took more than 15 hours to traverse some 1,200 kilometers.

Solar Impulse 2 is dividing its first around-the-world journey into 12 legs, flying at speeds between 50 and 100 kilometers per hour. The plane gains altitude during the day and drifts downward at night to help conserve its batteries.

Chongqing, the largest city in southwestern China and Nanjing were chosen as its only two stopovers in China, says Borschberg, Solar Impulse's CEO and co-founder.

"Solar Impulse 2 is living proof that green technology can do miracles," says Piccard, Solar Impulse chairman. Piccard says he believes China is working to become the top market for clean energy given that the nation already is a leader in a lot of green technologies.

China has replaced the United States as the world's largest renewable-energy investor with the rapid development of the solar and wind energy industries, according to a report by research company Bloomberg News Energy Finance.

Thanks to China, solar energy has now reached a level in terms of cost in which it can compete with other kinds of energy, says Borschberg, who adds that the country still is playing an important role in increasing capacity and reducing cost.

"Solar Impulse 2 is the first solar airplane that has attempted to fly around the world without a single drop of fuel, but with solar energy only. This is indeed a marvel in the sky," Jean-Jacques de Dardell said.

"If you don't fly to the Empire of the Middle, you don't really fly around the world," Piccard says, referring to China. He says he first visited China in 1992 to study traditional Chinese medicine and Taoism. Piccard says he has found that Chinese philosophy has always been an inspiration for him throughout the years.

"Our goal is not to complain about a problem, but to bring solutions," he says.

Solar Impulse 2 was expected to stay at the Nanjing Lukou International Airport for more than a week before taking on one of its biggest challenges, the flight over the Pacific Ocean to Hawaii, a solo flight of five consecutive days and five nights. The plane is designed for the pilot to take small naps. If there is a major problem, the pilot, trained in ocean survival, would have to bail out, London's Daily Mail reported.

The solar plane made stopovers in India and Myanmar before reaching China. Plans call for it to cross the Pacific Ocean, the United States and the Atlantic Ocean before crossing southern Europe to arrive back in Abu Dhabi in August.

By using solar energy only, the trip is intended to set an example for use of clean technology in the future. Compared with regular airplanes that have to be maintained every 10 to 50 hours of flying time, the solar plane can fly between 150 and 200 hours before maintenance, and the solar cells could be used for 25 years, according to Borschberg.

"If it were not energy efficient, it would crash before the end of the night, because it would use up its batteries and would not be in the air when the sun came back up," says Piccard.

"The Solar Impulse project impressively demonstrates how our innovations can help preserve the planet and its natural resources, improve people's lives and create value," says Richard Northcote, executive member responsible for sustainability from Bayer MaterialScience, one of the 80 technological partners of the 2.3-ton ultralight aircraft.

"Solar Impulse inspired new ideas in the field of lightweight construction, which in turn aids the automotive industry, where metal and glass on doors and roofs are now increasingly being replaced by plastics," adds Northcote.

The primary purpose is not to revolutionize aviation, but the way in which people think about energy and clean technologies, the projects backers say.

If Solar Impulse technologies were used on a massive scale, the world would be able to save up to 50 percent of the current consumption of fossil-fuel energy and produce half of the rest with renewable energies, they say.

Approximately $160 million has been invested in the project since it started 12 years ago.

Lyu Chang contributed to this story.

wang_ying@chinadaily.com.cn

(China Daily European Weekly 04/24/2015 page15)