Pioneering Solar Impulse 2 To Crown Its US Journey
Rolling hills, greening woodlands, and orderly farms grace Pennsylvania’s Lehigh River valley, where Solar Impulse 2 landed on the world’s first solar-powered circumnavigation last week. Small cities—Allentown, Bethlehem, Easton—dot the piedmont countryside.

You would never expect the peaceful Lehigh Valley to be hosting a high-tech superstar of the 21st century. However, the area’s coal mines and steel plants ushered in the American Industrial Revolution. Philadelphia and New York lie within a 100-mile radius, and the sub-Appalachian hills are the fastest-growing region in Pennsylvania.

CleanTechnica reporters in the valley found that it also houses many light planes and a small airport designated “international” only a year ago. On weekends and holidays, dozens of gliders—powerless cousins of ordinary aircraft as well as the experimental Si2—lazily circle its skies.
Joining the gliders now is a new aircraft as wide as a 747. It looks like another glider but really flies using power like a regular plane. This gigantic single-winged dragonfly has now traveled two-thirds of the way around the world without any liquid fuel. It has never needed a fill-up of aviation gas from airport hoses. Solar energy alone, captured by SunPower solar panels and stored chemically in lithium-ion batteries, has propelled the entire trip.
The plane’s inventor and pioneer Bertrand Piccard and Air Force pilot–engineer André Borschberg, CEO of Solar Impulse, are taking turns flying the record-shattering vehicle on its multi-stage odyssey around the world. Solar Impulse 2, as we covered, originally left its home base in Abu Dhabi, capital of the seven United Arab Emirates of the Middle East, in March 2015. (The original Solar Impulse, this plane’s prototype, set 8 world records on earlier journeys. Si1 was the first solar plane ever to fly through the night, something we covered way back in 2010; the first to fly between two continents; and the first to travel across the United States.)
With more solar cells, more powerful motors, and a 20% longer wingspan, the newer aircraft made stops in Oman, Myanmar, China, and Japan before starting US travel. Thermal damage during the leg between Japan and Hawaii delayed its flight during the winter, but it is back in the air again.
Over the past few weeks, the featherweight carbon-fiber craft has sped across the United States from Hawaii, where CleanTechnica met with it for the 3rd time, to northern California, to Phoenix, then across the nation’s Tornado Alley into Dayton, Ohio, on May 26, 2016. Orville and Wilbur Wright, the American brothers who invented, built, and flew the world’s first successful airplane at Kitty Hawk, North Carolina, hailed from the Dayton area. Piloted on the next leg of the journey by its Swiss inventor, the plane headed off from Dayton to the Lehigh Valley before dawn last Wednesday.

It took Piccard 16 hours and 49 minutes to guide the slow-flying plane carefully into the Lehigh Valley. (Si2 moves at about the speed of the average car.) Along the way, the pilot snapped a happy selfie from a camera outside the cockpit. Clear skies and a light breeze that night carried the aircraft onto the tarmac to cheers from the crowd of solar advocates, Swiss visitors, and rapt locals who waited there for the nighttime touchdown.
Piccard’s fuel for the trip? “Passion,” he told a news conference outside the Lehigh Valley hangar. Later, he elaborated for CleanTechnica:

“The future energy of the world is electric. Not necessarily renewable energy, because renewable does not always mean profitable. It is cleantech energy that will power development in the future. Efficient, profitable cleantech.”
The unconventional solar vehicle will take off for JFK airport in New York City on the last US leg of its high and quiet journey within the next few days. Join and follow Solar Impulse 2 at the #futureisclean hashtag on Twitter, and stay with CleanTechnica as we bring you more details on the plane’s technical systems and on the highlights of Si2’s upcoming layover in New York.
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Explain what energy sources are meant by “efficient, profitable cleantech”?
Onshore wind and PV solar. Offshore wind and thermal solar stand a good chance of joining in. Geothermal, hydro and tidal are also players but geographically limited.
Can some of the profit be used for storage for solid reliability?
That’s not how it works. Storage systems make their own profit.
As a rough example someone will own a wind farm and sell electricity at 4 cents per kWh. Someone else will own a storage facility that uses batteries, for example, and will charge up their batteries with 4c electricity.
Then when the grid needs electricity the storage facility will sell their electricity for 4c + their costs + profit.
We don’t yet need large scale storage. There’s still plenty of dispatchable generation (natural gas and hydro) that can be turned off when wind and solar are producing.
If battery storage already has a different primary use, such as mobility, why not just use excess for its margin cost, zero, plus profit, for nonproduction periods?
Sandy or Bob, what did Piccard mean by: “Not necessarily renewable energy, because renewable does not always mean profitable,” please? The last LCOE I saw suggested otherwise.
I don’t know. That statement does not make sense to me. Perhaps he isn’t aware how inexpensive wind and solar have become?
I’m not aware of any renewable facilities that operate at a loss. Most electricity from solar and wind farms is pre-sold via PPA contracts. Profits are built into the contract price.
Thanks, Bob. We agree on this. I would have thought Sandy might have parsed Piccard’s odd comment for us a bit.
She should pick up on this. I think she checks comments.
If one isn’t paying attention to current prices they could easily be walking around with bad info in their heads. The EIA has done a terrible job of misleading people with their projected cost crap.
It’s very common to run into people who looked at the Wiki page and came away with wind at 8 cents and PV solar at 13 cents. More than double current unsubsidized PPA prices.
Have you edited any wiki pages? Sounds like it could use it. I once edited the vegan page.
I haven’t. But I noticed a few days ago that someone had posted a “this data may not be accurate” warning. And they’ve added in other data that’s more reality based.
Previously if one looked for cost of wind and solar on Wiki they got the EIA numbers only.
I believe M. Piccard was referring not to the renewable successes, which Bob cites, but to renewable technologies that have been tested but do not work out currently from a cost perspective.
Thanks for clarifying, Sandy.
A lot is made of the fact that the solar cells power the plane. However, I wonder and maybe someone out there knows, does the plane charge from an outside source when it is on the ground? The reason I ask is that we see pictures of the plane inside its traveling inflatable hanger and then are told it takes off before dawn. During its descent to land can the motors “regen” so that it can land with a full charge?
It generally lands highly charged. They don’t actually regen by descending, but since they don’t use any energy descending, if they land in the daytime the solar panels are charging and the batteries are not being discharged, so they’re gaining energy as they land.
One slight correction: Sunseeker, piloted by American Eric Raymond, made the first trans-US flight for a solar plane in 1990.