The Solar Impulse 2 is a quarter of the way through its amazing round the world flight which started in Abu Dhabi on 9th March. The manned aircraft hopes to not only complete a new world record but also send a message about clean renewable energy to inspire the world.
The paneled plane is fitted with 17,000 solar cells that allow it to collect the sun’s energy and use it to power four electric motors as well as recharge custom made lithium batteries that store power for after dark. This combination of photovoltaic cells and batteries allow the Solar Impulse 2 to fly nonstop around the clock.
The cells are flexible and are around twice as efficient as the type of solar cells that we see on the roofs of homes. As well as being self sufficient and a test of the newest solar technology, the aircraft will also test the pilots over the rest of its round the world journey. The Solar Impulse 2 is a lightweight plane that has a huge wingspan- 72m is wider than a 747 jumbo jet but the solar plane weights only 2.3 tons and flies at a slow speed of 70 km/h. The cockpit is just 3.8 cubic meters large and only one man can fit in at a time so the two swiss pilots Bertrand Piccard and Andre Boschberg must take it in turns to pilot the aircraft. They fly for up to five days each but can only sleep for 20 minutes at a time.
As the Solar Impulse 2 completes each leg of its mission, a traveling team of engineers are there to meet it along with a mobile hangar for when the plane is not in the air. The mission is controlled from Monaco and from there the team decides whether conditions are right for the plane to fly. Although the plane has been tested, it is not a given that the mission will succeed, particularly on the Atlantic sea crossings. The pilots may have to wait for up to 30 days for the correct weather conditions, as happened last May during the testing phase.
The price of solar panels has fallen sharply in the last few years and they are now becoming affordable for homes worldwide, backed by many government schemes. The technology has also progressed, as the Solar Impulse 2 is a project that could not have been completed even 10 years ago. The custom lithium batteries used in the aircraft may help to develop new ways of storing solar power to make panels more efficient and more viable for the majority of buildings. Solar power jobs already outnumber coal in the USA and the industry is set to boom following the round the world flight.
Each pilot has their own techniques to keep them alert and get them through the gruelingly long hours flying the record-breaking solar plane. Pichard is using self hypnosis while Borschberg is hoping yoga techniques will help him cope. Boschberg is a former air force pilot, while Pichard has a little more world record experience under his belt. In 1999 he completed the first non-stop round the world balloon trip, his father was the first man to reach the Mariana Trench, the deepest part of the ocean, while his grandfather was the first person to reach the stratosphere in a balloon.
The Solar Impulse 2 has reached the fifth out of 12 planned stops around the world and will take off from China to land in Hawaii next. The aircraft was ridiculed by the aviation industry when it was first unveiled, but is now well on its way to completing its record-breaking round the world mission and landing back in Abu Dhabi in the spring.