This revolutionary solar-powered plane is about to end a slow and symbolic journey across America by quietly buzzing the Statue of Liberty and landing in a city whose buildings often obscure the power-giving sun. The plane's top speed of 45 mph is so pokey, it would earn honks on the New Jersey Turnpike.

The plane is called Solar Impulse.

And it leaves from Washington on a commuter-like hop planned for Saturday, depending on the weather. It will take hours for the journey and offers none of the most basic comforts of flying.

But that's OK. The aircraft's creators say its purpose really has little to do with flying.

They view themselves as green pioneers—promoting lighter materials, solar-powered batteries, and conservation as sexy and adventurous. Theirs is the high-flying equivalent of the Tesla electric sports car. They want people to feel a thrill while saving the planet. Think Charles Lindbergh meets Rachel Carson.

And if there's one person who knows about adventure and what it means to Earth, it's Bertrand Piccard.

He's one of the two pilots who take turns flying Solar Impulse. His grandfather was the first man to see the curve of the Earth as a pioneering high-altitude balloon flier more than 80 years ago. His father more than half a century ago first took a submarine to the deepest and most inaccessible ocean trench on Earth.

And now in the 21st Century outside the Smithsonian's Air and Space Museum annex not too far from a retired space shuttle, Piccard says there's no truly new place on Earth for explorers to pioneer. At 55, he's tried.

He already was the first person to fly around the world non-stop in a balloon, but that wasn't really enough. So Piccard found a way to explore by looking inward and acting globally.

"It's an exploration of new ways of thinking," said Piccard, who is also a psychiatrist. "It's important to understand that pioneering is not only what you do. It's how you think. It's a state of mind more than action."

"After a conquest of the planet, the 21st Century should be about improving the quality of life," Piccard said. And the lightweight beanpole that's called Solar Impulse "is something spectacular in order to capture the attention of the people. If you make a solar bicycle to drive, nobody would care. If you make a solar plane, everybody cares. Everybody wants to see it.'"

Europe saw it first with a test flight from Switzerland and Spain to Morocco last year. This year's U.S. flight is another trial run that's really preparation for a 2015 around-the-world trip with an upgraded version of the plane. Solar Impulse has been to San Francisco, Phoenix, Dallas, St. Louis, Cincinnati and Washington. All that's left is New York's JFK Airport and Piccard talked about having to wait his turn to land with all the big jets.

"We're flying the most extraordinary airplane in the world," Piccard said.

Although it's promoted as solar-powered, what really pushes the envelope with this plane is its miserly energy efficiency, said Solar Impulse CEO Andre Borschberg, the plane's other pilot.

Parts of its wings are three times lighter than paper. Its one-person cockpit is beyond tiny. Borschberg lowers himself gingerly into it for a television camera, grimaces, and practically wears the plane it is so snug on him.

Most of the 11,000 solar cells are on the super-long wings that seem to stretch as far as a jumbo jet's. It weighs about the size of a small car, and soars at 30,000 feet with what is essentially the power of a small motorized scooter. When it landed at Dulles International Airport in suburban Washington after midnight on June 15, its wings were lit with 16 LED lights that used less power than two 100-watt bulbs.

"We can use much less energy than we use today without the sacrifice," Borschberg said. "And that's really important."

People won't sacrifice to save energy or the planet, but if they are smart they don't have to, Borschberg said. That's why he and Piccard pointedly talk about "clean technologies" not "green technologies." They think "green" has the image of sacrifice. Read the full story at www.solaronlamp.com web.