The Solar Plane – a Perfect Metaphor for What is Wrong With Renewables

Solar impulse at Brussels Airport, author Brussels Airport, Wikimedia share license

Solar impulse at Brussels Airport, author Brussels Airport, Wikimedia share license

Guest essay by Eric Worrall

The Solar Impulse 2 has finally completed completed the latest leg of its round the world flight. In engineering terms, a round the world flight using solar power is a remarkable achievement. But the difficulty of achieving this feat showcases why solar energy will never be a viable replacement for fossil fuels.

An experimental plane flying around the world without a single drop of fuel landed in California after a two-and-a-half day flight across the Pacific.

Piloted by Swiss explorer and psychiatrist Bertrand Piccard, Solar Impulse 2 touched down in Mountain View just before midnight (3 a.m. ET).

“It’s a new era. It’s not science fiction. It’s today,” Piccard told CNN from California after his successful voyage. “It exists and clean technologies can do the impossible.”

Images of the elegant solar aircraft, which has the wingspan of a Boeing 747 but only weighs about as much as an SUV, flying over the Golden Gate Bridge into San Francisco Bay mark a significant achievement. The team has seen the project beset with problems and setbacks during its pioneering airborne circumnavigation.

“I’m very happy that everything works extremely well and the airplane is functioning as it should,” Piccard’s business partner and the plane’s other pilot, Swiss engineer Andre Borschberg, told CNN by phone from California just ahead of the successful, on-schedule landing.

“It’s a demonstration that the tech is reliable.”

The plane took off from Hawaii on Thursday, resuming a journey that had stalled on the island of Oahu for almost 10 months.

Read more:

Solar planes can’t carry meaningful amounts of cargo. They can barely carry passengers.

I am not disrespecting the talent of the engineers who achieved this feat. Flying a solar plane around the world is a remarkable achievement. But this achievement does not demonstrate the technology is viable. What it demonstrates is that solar is a ridiculously poor source of power. A solar collector the size of a 747 just managed to collect enough electricity, to keep an incredibly lightweight plane aloft.

Just like solar panels, solar planes might find some niche uses, such as long life high altitude robotic observation platforms, or even as mobile telephone repeater stations – solar planes are not restricted by fuel payload, and can reach very high altitudes, because they don’t depend on burning fuel with oxygen for their power.

Solar planes will never replace fossil fuel powered planes, for ferrying people and high value cargoes across vast distances.

Update (EW): h/t etudiant – the flight is not yet complete…


newest oldest most voted
Notify of

..Holy Flag Post Batman..errrr, I mean Anthony..Is this a record number of great posts in one day ??

My earlier take on Solar Impulse:
Stranded monster lands at Oahu
Now and then giant ocean creatures wash up on beaches in a horrible mess.
At Kalaeloa Airport on Oahu (Hawaii) a similar but aerial creature has washed up in an airport hangar. It’s the Solar Impulse 2, a solar-powered plane with a wingspan nearly as long as an Airbus A380’s. But it weighs rather less than a Toyota Land Cruiser and has so far cost its sponsors about $US250m.
It was meant to fly around the world – without using a drop of fossil fuel – from March to August this year (2015). Cheering it on were bigwigs Prince Albert 11 of Monaco, ex-UN czar Kofi Annan, Virgin’s Richard Branson, the ubiquitous Mikhail Gorbachev and the IPCC’s figurehead Christiana Figueres. Among the plane’s partners are champagne people MoetHennessy, who supplied refreshments at each stop “to promote their common values” with “beautiful occasions”.
Departing Abu Dhabi, Solar Impulse 2 got half-way in 200 days, but it’s going nowhere until next April (2016). That’s because its solar batteries overheated during a wrong flight pattern and have to be replaced.
The fuel-free plane was meant to show the delicious potential of clean solar energy, “therapy for the planet” and a climate-change stopper, as its founders balloonist Bertrand Piccard and ex-Swiss air force man Andre Borschberg see it. The solar plane’s actually demonstrated the superiority of a few drums of avgas.
Its 17,200 solar cells generate 17 horsepower for each of the four props – less than half the grunt of my four-cylinder Camry. It can lift only one person – the pilot. (Freight? Zero, not counting all the “messages” and “positive emotions”). The pilot can last about five days and nights in the air, taking catnaps and using his seat as a potty-chair. Strangely, the Wright Flyer 111 in 1908 carried a passenger.
The solar plane is at the mercy of sun and breezes. It was held up at Nagoya for a month waiting for favorable winds, much like a 17th century galleon.
But there’s more. To keep this gossamer confection airborne, an Ilyushin 76 strategic airlifter flies ahead with a blow-up hangar and all the high-tech servicing gear. Aviation buffs call the four-engined airlifter a ‘bad-ass’, not just because of its ugly nose and droopy jets, but because its takeoffs are real Russian screamers. Once aloft, it burns eight tons of CO2-spewing avgas per hour.
This behemoth is accompanied by a twin-turboprop ATR72 which can carry a support crew of up to 60, apart from the dozens left at Monaco mission control. The ATR burns a more modest ton of fuel per 90 minutes.
With these two little helpers, the solar plane flies (half) round the world “without using a drop of fuel”. Piccard says, “What we have here is the future.”
Well maybe. This futuristic plane cruises at about the top speed of a postie’s bike, but can sometimes accelerate away to 90km/h.
Charitably assuming the plane does make it round the world in 18 months, that compares with other round-the-worlders such as
# The Graf Zeppelin in 21 days in 1929.
# Wiley Post in his Winnie Mae, in nine days in 1933
# The Rutan Voyager, non-stop non-refuelled in nine days in 1986
# Bertrand Piccard and Brian Jones by balloon in 20 days in 1999.
# Solo yachter Francis Joyon, in 58 days in 2008, using that other clean fuel, wind.
# Someone could walk the plane’s route (somehow) in two years, not much longer than the flight time.
Piccard, who partakes of green delusionism, has summed up the venture: “Protecting the environment should not be perceived as expensive… Fighting climate change is opening-up new industrial markets and offering an opportunity for economic development, job creation and profit.”
I can picture a fourth-world peasant looking up from his hoe and saying, “Kids, that’s a quarter-billion investment whirring along up there using clean energy. And it’s worth it!”

Dr. Strangelove

Garbage! Literally garbage can do better than this $250-million solar plane. Piccard just lacks imagination. He can build an airplane that’s ten times faster (900 kph) powered by household garbage using World War II technologies. The Germans built a jet plane in 1942 and made synthetic diesel from coal via pyrolysis and the Fischer-Tropsch process. Piccard can just replace coal with household garbage and use the same processes to produce fuel for a jet plane.

David Ball

I love this line;
The plane took off from Hawaii on Thursday, resuming a journey that had stalled on the island of Oahu for almost 10 months.


If my memory serves right the plane left Japan after a 4 month delay because the original flight from China to Hawaii was blown off course.


flight from China to Hawaii was blown off course
Only a minor detail when #SavingThePlanet™, comrade.

Not much emphasis on that stupendous failure to achieve its original highly-promoted objective!

Don K

Around the World in 80 years?
Not a promising technology
OTOH, I’m old enough to remember a world without jet aircraft and it didn’t work all that badly. And when you get down to it, modern air travel is an incredibly unpleasant experience. Lots of stress. Interminable hours stuffed in a tiny seat. Preposterous (and mostly theatrical) “security”. And not all that reliable if the weather doesn’t cooperate. I quit flying years ago, and it amazes me that the rest of you tolerate that crap. Are you daft?
I think that eventually rigid, solar powered, lighter than air craft might someday work OK for a lot of people a lot of the time. After all, the Graf Zepplein made a round the world flight 85 years ago carrying a substantial crew and a few passengers. More like a fast ship that could travel over both land and sea than a fixed wing aircraft. The trip took about 9 days of flying time. (I’d guess we could do a bit better today). But you could get up and walk around, eat decent meals, and sleep in a bed.
And do keep in mind that the current period of cheap oil isn’t the result of (cheap) oil being abundant. It’s the result of most economies worldwide sucking. You’ll most likely see $100 a barrel and more crude again in not all that many years. Your grandkids will likely live to see a world that uses a lot of alternative, non-fossil, based technologies because fossil fuels cost too damn much.

Patrick B

” Your grandkids will likely live to see a world that uses a lot of alternative, non-fossil, based technologies because fossil fuels cost too damn much.”
This statement sounds a lot like the stupid statements in the 70’s about how the world would be out of oil by 2000. I imagine it has the same validity. By the time our grandkids are grown, global warming will have been definitively disproved as a significant threat and the US will be joining China and other countries that never stopped mining coal, and fracking will be used worldwide. The only difference will be the relative poverty of the US economy as compared to China, India and other countries who will have never stopped using fossil fuels.


I’ll let my great-grandkids, using technology that isn’t even invented yet, worry about that problem.


“… because fossil fuels cost too damn much.”
That’s because they pay too much taxes and are not subsidized like the unreliable and expensive to produce green energy. In the US gasoline costs about $2/GALLON even with over 25% of that state and Federal tax. Then add in the income tax, royalty,and lease costs that the government extorts which all go into that price. I am surprised it is that cheap. Revenue from oil companies income tax is the second largest source of income to the US Treasury
Where will the government replace all that huge stream of income to the US Treasury when they put the fossil fuel companies out of business.
The Pentagon was forced by government policy to purchase fuel for the Navy at $25/ GALLON and in some cases even 10 times that amount to prop up a subsidized biofuel manufacturer who is a bundler for the President. Meanwhile there is not enough funding to maintain the aircraft and ships we need to protect us.
In the UK the tax on motor fuel is much worse, I know I lived there.
Who is “daft”?

Don K

You think it’s stupid because you haven’t looked at the data. You can do look into it, or you can wait a few decades and see if I’m correct. Waiting’s OK BTW, there’s not much you can do about the situation individually other than thinking twice before buying a huge house assuming that heating it will be cheap.
Some things you might want to consider:
. The future energy demands of about 5 or 6 billion people in China, India and 100+ other countries who are living in various degrees of poverty and have every intention of fixing that situation.
. The places where oil companies are looking for new oil and the probable cost of the oil produced.
. The fact that the highly touted US shale oil revolution is largely (not entirely, but largely) based on a failure to understand how hydrocarbon production is reported. A very large part of what folks assume to be oil is Natural Gas Liquids. NGLs aren’t liquids at room temperature and pressure and aren’t especially easy to convert to liquids. (It can be done, but it’s not cheap — think $7 a gallon diesel before taxes.)
. The fact that the production from fracked oil wells falls off rather quickly. Which means that new wells have to be drilled continuously. Which won’t happen if the oil can’t be sold for enough money to pay for the drilling and fracking. Might want to check the Baker-Hughes rig counts to see the impending problem there.
BTW, I’m not asserting that we’re going to run out of hydrocarbons any time soon. Nor do I think that the developing world is going to pay much attention to the developed world’s exaggerated beliefs about climate change. (They may worry about pollution from hydrocarbons when it gets to be as severe as in China’s air quality problems). Humanity won’t run out of hydrocarbons for a century or three.
I’m just telling you that those hydrocarbons almost certainly won’t be as cheap as you think.


DonK, it never ceases to amaze me how some people will ignore everything that contradicts their peculiar religion.
I have spent years studying the data, not just glancing at carefully preselected fact, most of which are wrong to begin with, and I have reached the opposite conclusion.

Don K

> I have spent years studying the data, not just glancing at carefully preselected fact, most of which are wrong to begin with, and I have reached the opposite conclusion.
In that case, you should certainly borrow against all your assets and make a huge leveraged bet on eternally cheap hydrocarbons.


You know that you are dealing with either an idiot or a liar, when you counter someone’s claim that fossil fuels are about to run out, and he responds that you believe they will last forever.

Kalifornia Kook

Flying didn’t use to be stressful. It used to be incredible fun! I remember looking forward to flights. People dressed nice, stewardesses were always friendly, friends and family could accompany you on board to see you off. You could visit the cockpit to see all the marvelous gauges and controls. I loved the old DC-6, and was so excited about flying the Caravel when it entered service with United. Lots of room, and you were truly ‘free to move about the cabin”.
Then came DB Cooper, and a few others wanting to go to Cuba. Friends and family could no longer accompany you on board. Still, it wasn’t that bad. You could really wow a girlfriend by flying her from San Diego to Los Angeles and back for dinner – on a college student budget. Not every weekend, but often enough to start a trend. Ah, I loved PSA!
Then seats started shrinking in both width and pitch. People started wearing ‘comfortable’ clothes on board, and since they were ‘comfortable’, they didn’t have to be civil. Of course, I realize a lot of that had to do with deregulation, but could easily have been fixed with a simple law (for minimum width and pitch). Instead, there is no protection for the regular-sized person who has to sit next to a 400-pound, sweaty guy in economy class, who requires two seat belt extenders to get belted in, despite the fact his belly is in firm contact with the seat ahead of him.
Years later, we endured 9/11. Suddenly, passengers were all suspected terrorists (unless you looked like one). TSA stuck their hands down the front of your pants to make sure you weren’t smuggling nukes, and pawed through all your luggage. Lines that stretched for a mile. Five hours before you got to your plane. Non-travelers not allowed near the gate area, let alone the airplane. You realized you left your phone on the plane, but you couldn’t go back and check, even though you hadn’t left the gate yet. Some of that has been fixed with imaging machines that effectively render you naked for inspection, and x-ray machines for your luggage. Somehow, I still don’t feel human – more of a chunk of meat to be transported. Except I’m a suspected criminal to boot.
So now when we consider flying, we realize we have to surrender our humanity, and face hours of misery, unless we’re willing to pay for Business or First Class. Fine if you’re an executive, or wealthy. The rest of us just suffer. But now you know why I love Amtrak, despite those early memories.
Now comes Solar Impulse 2, with the ‘hope’ of a future where that two-hour will be a 10+ hour flight, in a space so cramped even the pilot is in pain. Ah, I love progress.

Jay Hope

‘around the world in 80 years’. Love it!

Thinking there is plenty of oil left is a reasonable position.
Thinking it is “about to run out” is the silly bit.
Even IF Hubbard’s Peak is real AND we are on the peak now (both not facts in evidence), then the bell shaped production curve has us producing oil for about as long into the future as the past, so about 150 years, (yes, at decreasing rates. so what. Folks in 2106 A.D. can worry about that as they drive their fusion car to the antique car meet…)
That fact caused The Green Blob to dream up a sudden catastrophic cliff fantasy called EROEI Energy Return On Energy Invested. The notion that as soon as it takes a kW to lift oil with a kW of fuel energy, you stop. That is daft as the FORM of energy matters. We have effectively infinite nuclear power available to lift oil for fuels (THE dominant use is motor fuel due to the liquid form being near ideal…)
Hypothetical? Nope. Not at all. Nuke power from Palo Verde flows to California where we have electric driven oil wells. That oil gets refined to fuels. EVERY refinery is a Negative EROEI operation. So why do we do it? The form of the fuel matters. A Lot.
Oh, and a cat reformer to turn propane and other nat gas liquids into gasoline is fairly cheap. That $7 claim is quite bogus. You can make Diesel from coal via a similar and more expensive process for about $4 / gallon. and Shell along with several others has GTL Gas To Liquids plants putting gas as gasoline in tanks now in several parts of the world.
Oil is a worry in maybe 1/4 century. Maybe. But then shales, tar sands, clathrates, etc. become economical and there’s about 10x as much of those, so the worry becomes a problem about 2275 A.D., maybe… or maybe we use high temp gas cooled reactors to turn kerogen and coal and garbage to gasoline and Diesel for another 400 years. We already can do it. A VW study from the 1970s showed economical at about $4/gallon in current dollars (my napkin math convert of 50 ¢ gallon metanol in 1975 to current dollars. Methanol to gasoline is one step more with zeolite catalyst in the Mobile process from the same era.). So maybe it will be 2700 A.D. before it really is a problem.
Then again, by then, I think they will be using better technology than from the 1970s…
BTW, I started study of all this in great depth due to The Arab Oil Embargo of the ’70s, that lead to all those other paths to motor fuels…. that drove oil prices back down…

George Tetley

I can remember buying gasoline in a “Scott Gas ” station in Delaware for 0.98 cents a gallon used to fill my straight eight Pontiac 2 times a week, TODAY?

Gregory J Suhr

I like lighter than air aircraft….but…..what gas are you going to use to lift them? Helium is a “fossil gas” and is in limited supply and hydrogen brings up images of the Hindenburg….in flames.
Also…when you are lighter than air, that moving air…wind…becomes a huge factor. If you want to go in the direction the wind is blowing, great, if not….well you either need a lot of power or a lot of time. Landing is an issue in any case..
Finally,,,,the Hindenburg round trip ticket cost $700 in 1937, the equivalent of roughly $1200 today. I’m flying round trip to Europe in August….for roughly 1/10th that amount. I’m willing to spend some cramped hours with poor food to save enough to spand a week cruising down the Rhine in comfort.

george e. smith

Um er ! Please sir, it is against the law to collect solar energy in California around midnight. That’s when all solar collectors are supposed to be asleep.
Also it only takes 24 hours for the sun to go all the way round the earth, so why did this plane not just keep up with the sun, and do the whole trip in sunlight all the way ?
I don’t think this mode of transportation will ever catch on. Pretty bad when you have to wait on the ground in Oahu, until the solar flying season comes around again.

george e. smith

I seem to recall that two people actually flew a fossil fuelled aircraft completely around the world, without ever setting down on the ground, so they did it all on one tank of gas.
That in my view is a real accomplishment. This latest is just an example of how much money you can spend chasing rainbows.
Nothing useful, will ever come of this.
Now the guy that rode his bicycle through the air across the English channel; that is a real accomplishment, but also not practical. He at least did it under his own head of steam.

How about this. “We had stopped at Oahu to build another leg of the transpacific undersea railroad.”

Stalled on the island for 10 months! Imagine taking an extra 10 months to get somewhere.
Add in the fact that this thing probably cost tens of millions of dollars to make.


Imagine abandoning the use of fossil fuels altogether? And then imagine that the only way to travel around the world is by ship with sails or people using oars. Don’t scoff at the ideology–there are actually people who think this is a good idea. Welcome back to the 2nd century.

phil cartier

I think that anyone who ascribes global warming to CO2 must prove it by adhering to their beliefs and not use any fossil fuel sourced energy- only wind for travel hydropower for electricity and solar only for passive heating, and beeswax candles for lighting. Solar panels are a no-no. They can’t produce enough electricity to reproduce themselves, neither can wind mills.

Leo Smith

well I did try imagining it.
You can read what I came up with as just within the bounds of possibility, here:

Patrick B

It’s not that those people think this is a good idea, they think it is a good idea for others. For themselves, well, the importance of their activities justifies continued use of private jets.


Phil, I agree. I have said many times make the elite who govern us live be the first to live by the rules they establish for 5 years to see “how that works out”. Somehow they wrangled their way out of Obamacare although the law said they were required to use it. We know the person who admits to the largest carbon footprint in the world wants us to live in energy poverty.

Don K

Leo Smith, I read through your Beyond Fossil Fuels paper. Not surprisingly, I have a lot of quibbles, but mostly I agree with it. A couple of my more substantial quibbles.
1. It’s somewhat GB-centric. An analysis for Hawaii, Quebec, or Australia might be substantially different in some respects.
2. Nuclear does seem to be a major part of the solution worldwide although there are a few areas where the combination of favorable non-fossil fuel resources (geothermal, hydro, or even wind/solar plus pumped storage) and favorable population dynamics might make non-nuclear alternatives practical. No reason not to use them if they are available and cost effective.
3. We don’t currently have a nuclear design that mismanagement can’t “blow up”. We really such a design before mankind builds maybe 20000 nuclear reactors (Pebble beds maybe …)
4. By the time humanity actually runs desperately short of fossil fuels, the technology for synthesizing them will probably be greatly improved and the need for them much reduced — long distance air travel, emergency equipment (You want to depend on a battery powered ambulance or fire engine with grid access down?), access to remote areas, perhaps some mining activities and some agriculture.
5. You don’t seem to care for personal transport. And perhaps that’s reasonable in England. But let me tell you that Americans and Canadians (outside of NYC) aren’t going to give up their cars without a fight. And, in fact battery powered cars with a small supplemental generator for an occasional holiday can probably meet most of their perceived needs.
6. In theory, sunshine plus efficient storage can satisfy humanity’s energy needs. It’d involve more solar panels than anyone will want to see and a lot of storage. At the moment that pretty much means pumped storage The US has something over 20GW of pumped storage in place and a lot of it is actually used. Are there enough sites (and enough water) to meet humanity’s needs? No clue.
But overall — well-done!!!

Jay Hope

2nd Century? More like the 19th!

Steve Fraser

Jules Verne would not have been impressed with the timing…

He was only off by an order of magnitude – 800 days rather than 80 days.

R. Shearer

Hawaii was better than say Newark or Philly.

Bryan A

17,000 special solar panels mounted on the surface of a wing longer than a 747 and fuselage of a 5000lb aircraft to fly 1 person from Hawaii to San Francisco in 62 hours at 28 mph … highly impractical!!!

Gentle Tramp

In addition: It’s simply a blatant deception to claim that this round-the-world trip does need no fossil fuel ! Just see here for the real facts:


If the support planes had tow ropes they would not even need to use solar energy!

David Smith

Snail Mail is now a high speed courier.


“Stalled on the island for 10 months! Imagine taking an extra 10 months to get somewhere.”
Well, I’ve been to Maui twice, for a total of a month. I wouldn’t be trying to hard to “unstall” myself if I had the choice…


I guess I won’t complain nearly as much the next time I’m stuck on a plane at the far end of O’Hare (ORD) for 3 hours waiting out a summer thunderstorm… I hope Bertie brought some extra granola bars to snack on while waiting 10 months for departure 😉

Kalifornia Kook

According to they have spent 250 million USD. That’s right, one quarter of a BILLION dollars on this thing. And the original plan was to circumnavigate the globe in just five to six months – MONTHS! compare that to the Graf Zeppelin that did in in 21 days in 1929. The Graf did it without a four-engine Illushin 76 carrying supporting equipment for the trip, and a twin-turboprop ATR72 for the support crew.

Australian TV had the gall to announce this as “the future of aviation”! God help us if we have to build a 747 size rig to get one family across the planet in over a year of travel. My parents came to Australia as assisted migrants in 1949 in 10 weeks by ship.

The future of aviation if they build solar planes the size of San Diego to carry 100 people and use all of the CA Mojave and half of the Austrian outback for landing strips. Mine more environmentally friendly lead and atomic radionucleotide rare earths to make more batteries. More. More. And you flight time to California is one week. This is just rich boys screwing off. Generally, most aviation is not keen on moving back to balsa wood for aircraft structures.


My definition of outback is anywhere you would need the flying doctor to take you to hospital. Maybe some of Austria qualifies.


Don’t sneer at balsa wood airplanes. The Mosquito used a lot of it.


Buy stock in Testor’s Glue!

Johann Wundersamer

You sure mean Austria?
Peterg on April 25, 2016 at 6:53 pm
My definition of outback is anywhere you would need the flying doctor to take you to hospital. Maybe some of Austria qualifies.

Johann Wundersamer

Peterg on April 25, 2016 at 6:53 pm
My definition of outback is anywhere you would need the flying doctor to take you to hospital. Maybe some of Austria qualifies.
In Austria we have the problem of sporting every 100 miles a hospital, to many of them for a small country furnished with alps and rivers between the mountains so leaving small space in the living room.

Patrick MJD

Balsa wood is classed as a hardwood. And as noted above, used in WW2 aircraft as they were invisible to radar.


>>invisible to radar.
Actually, they chose wood because aluminium was getting very scarce and expensive, and skilled fabricators were just as rare. Meanwhile, we had plenty of wood and plenty of woodworkers, and everyone from cabinet makers to piano makers found themselves glueing bits of the De Havilland Mosquito together.
And very effective it was too. When empty it could outrun a Spitfire – on one engine. And when full it could carry 2/3 of a B-17 load over similar distances (1.8t vs 2.8t). (It was so fast – 100mph faster – it did not need five defensive gun positions, and all the men to crew them.)

george e. smith

Are you sure about that ??
Balsa wood would have had to come from South America in war time. I don’t think so.
Balsa is too soft to use for light weight highly stressed structures.
Yes it was built out of wood. I actually got to play around in the fuselage of one of them in a guy’s back yard, along with the RR merlin engines parts rotting in his yard (he had six mosquitos).
But the framing was much more structurally sound, like Ash for example, and very thin multi-ply skin.
The general idea was to use the furniture industry that was spread all over the country to build something with those skills.
But not so much balsa I believe. You might be able to use balsa to make the innards of a honeycomb structure, which doesn’t require a lot of strength for the honeycomb.
But not much honeycomb structures in the Mosquito; or the follow on De Havilland Hornet; son of Mosquito.

george e. smith

A Rolls Royce Merlin engine, is not invisible to radar, nor are two of them.
Speed was the name of the game not stealth.

george e. smith

Well ralfellis, you somewhat exaggerate the performance of the Mosquito. It was more than capable of making its own reputation, without making one up.
And the BofB Spitfire, which was actually a Hawker Hurricane, was not a speed match. But you get into a Mark XIV Spitfire, and you better hope your Mossie is running on two healthy engines.
But the Spitfire was built for home defense, not for a chase plane.
Both were good matches for the tasks allotted to them; no need to blow it all out of proportion.


Not making anything up, George. Top speed of the Mosquito 380 mph, top speed of the standard Spitfire 370 mph. The difference being that the Spit was stressed and built for manoeuvrability, not top speed.

Bryan A

Actually it would take 4 – 747 sized aircraft to fly a family of 4 to Hawaii in 3 days. Each plane only has seating for 1


As I understand the one person has to be the pilot so each of the 4 would have to train to be really good pilots


Australian TV had the gall to announce this as “the future of aviation”!

🙂 🙂 This makes my day, thanks. If there is one thing which is certain, it is that carbon-based fuels are efficient and economical and solar panel is both expensive and inefficient.


Probably quicker to walk!

Kalifornia Kook

Not sure. I calculate it would take 24 months to walk, assuming 10 hours off each day. However, if you ride a horse at just a trot – its most efficient gait, you should be able to make the trip in 8 months, although I’m not sure how you’re going to manage the oceans in either case!


So why didn’t your parents fly?

The solar plane has 4 17hp engines, compared to a 747 which has 4 15,000hp engines.
If batteries increase capacity significantly, I could see an electric plane becoming a possibility, but the amount of energy extracted from the solar panels on the wings would be a drop in the bucket compared to the energy needed for an intercontinental passenger flight.


Batteries don’t just have a capacity issue, they have reliable issues and shock resistance issues.
A tank of oil or even methane contains potential chemical energy but without an oxidizer it won’t do anything (well, the pressurized gas also has mechanical energy). OTOH, batteries come with the oxidizer.



And temperature at altitude. Batteries are generally unhappy at lower temperatures.

Moose from the EU

Yes, but the 747 weighs 300 tons +, flies at 12 km with 900 km/h, carries around 500 passengers…
“If batteries increase capacity significantly”
Thats what I always hear from the greenies, day dreaming.


It is very hard to get the J/kg value high enough in a battery. Really, really, hard.


At the moment.

Tom in Florida

So what is the comparative cost per passenger mile?


Toneb: They have been working to improve batteries for over 100 years. Just when is this breakthrough you are expecting going to arrive?

Patrick MJD

And consider many carriers are planning non-stop flights from Sydney, Australia, to London, UK, carrying more people and weight that a Boeing “Longreach” 747. This can be achieved only by improvements in air frame and engine performance. The turbo-fan jets on an Airbus A380 are at the leading edge in engine performance.


This was done a LONG time ago, with a (then) new 747/400 with extra fuel tanks.
It was not at all popular with the passengers. 24+ hours in the air was just too much. That was in the days where economy seats actually gave you a bit of space.
With super/hypersonic aircraft, maybe. With current sub sonics, no.


newer 747-800 / 787 GEnx turbofan are probably more cutting edge now

Leo Smith

Electric aeroplanes already exist and, within limits, perform well.
how far those limits may be pushed, economically, is the real question.
As with cars, range is the problem.
I have designed and built many electric model aircraft. Today you can get as good a power to weight factor as with a tuned IC engine.. for about a minutes flight …:-)


Of course they do. I’ve got 14 of them. They range from 400mm wingspan to 2.54 metres, & even my pre teen grand son can fly them, remote control offcourse.
The batteries are a nightmare, rarely lasting 12 months, even with extreme care.

Owen in GA

Why go with batteries at all? Why not use a small nuclear cell as used on deep-space craft? Encase the radioactive material in a steel, thick walled, rounded case so it is unlikely to break in a worst-case accident and have at it. Scale it up as needed for power production.
(I know the “N” word scares people to death. Why, just the thought of radioactive material flying over their heads would make certain people die just thinking about it!)

Paul Westhaver

Show me a plane that flies forever in the dark while carrying it’s own weight in cargo. Now THAT would be a technical marvel.


Cosmic ray panels?

Patrick MJD

No, just thought. It was demonstrated on Star Trek: TNG, and that’s real çoz it’s in colour!

Paul Westhaver

This just begs for the ‘what use is a baby’ comment. We should be sufficiently generous of spirit to applaud a substantial technical achievement, even if it is not immediately economic or practical.
Also it is not correct to say the plane has completed its round the world tour, it still has to cross the Atlantic and Europe to do that.
NASA in the 1980s did useful work on solar powered airplane concepts. One was based on a solar power satellite beaming power to the airplane. That circumvented the problem of low energy density provided by direct sunlight.

Be great for CIA drone strikes. Other than that, the technology is not in its infancy, it is worthless.


A drone, especially one that conducts “strikes” requires the ability to carry a real payload. Besides, though many don’t seem to consider this, fossil fuels ARE solar energy – concentrated into chemical bonds that permit the accessibility of the the energy at all times and in a much more stable and lighter form than a battery.


This is for Duster below. Fossil fuels are coal. Gas and oil are from the planet’s core and NOT fossil fuel and therefore not solar-derived energy. This is why we find gas and oil anywhere we drill deep enough.

AGM-114 Hellfire weight … 100–108 lb (45.4–49 kg)

Highley, I didn’t know we found oil and gas anywhere if we drill deep enough. Where did you get that idea? I just wrote a Peak Oil 101 post and I sure hate to have got it wrong.

chris moffatt

“Gas and oil are from the planet’s core and NOT fossil fuel and therefore not solar-derived energy…”
Oh dear! Is that what they’re teaching in Geology class these days? Back to school everybody – We’ve had it all wrong up to now. The good news is we won’t run out of oil and gas for a really long time.

David Ball

Fernando, i’ve seen your posts on the oil sands and you get a LOT wrong. You have zero credibility, imho.
chris moffat: are you speaking from knowledge, or are you just parroting what you have read. There are a lot of questions surrounding this subject. The science is definitiely NOT settled.


If that is true, that it has not actually completed its around the world flight, then it is yet another example of the hype and false narratives that surrounds almost every aspect of the entire climate change and renewable energy monologue.

Javert Chip

Sounds like trying to go to the moon by climbing a big tree: no matter how good a start you get, it ain’t gonna work.


Sounds like trying to go to the moon by climbing a big tree:

Spot on!


“The Solar Impulse 2 was originally supposed to land in Abu Dhabi, where it started its journey in March 2015, by the end of last summer.”

Hats off...

Well, if I was going to break down anywhere in the world for 10 months, there are places worse than Hawaii to do so.

I wonder if they are going to finish the trip or if they plan to just go quiet and hope everyone THINKS they’ve finished the trip. I thought at first they had finished, I guess because it took so long to get this far.


Hi from Oz. Hmm – ‘a solar power satellite beaming power to the airplane’. Sooo, the solar power collected by the satellite converts the DC power (ignoring the obvious storage issues for any significant amount of power) to say microwave energy (at maybe 50% efficiency), and then it is transmitted maybe hundreds of kilometres to the airplane (at maybe 0.00000000001% efficiency – see here: Enter 500 km, 2GHz, Tx antenna gain 20dB, Rx antenna gain 20dB, result -112dB path loss), where it is converted back to DC to power (at say a generous 90% efficiency) the airplane’s electric motors. Yeah, I used to read sci-fi comics when I was a kid, too, but even then I didn’t take them seriously because I was a radio amateur who understood about free space path loss! And BTW this hare-brained (or should I say “Heath Robinson” (see: – hint, he was a cartoonist, not an inventor) ‘solution’ does not ‘circumvent the problem of low energy density provided by direct sunlight’, it only makes it a gazillion times worse by trying to transmit useful amounts of energy via radio waves.

Tom Yoke

The link referred to in your post doesn’t work, but the very small efficiency you name must presume an omnidirectional radiating antenna. When space transmission of microwave energy is referenced it is always presumed that a MASER is being used.

Tom Yoke

The poor path efficiency of an omnidirectional antenna is the problem that un-did Nikolai Tesla. He wanted to deliver electrical power sent as radio waves from a central transmitter, and there are those wonderful pictures of light bulbs glowing in the dark with no wires or batteries connected. The problem, as you’ve pointed out, is that the efficiency declines as 1/(4 pi r^2). That is a disastrous decline and I’ve never quite understood why someone as smart as Tesla did not see that that simple fact made his idea impossible.


The solution is simple really. We just use exactly the same technology used to “Beam me up Scotty”. No need for old technology stuff like planes trains and automobiles.
(… Now beam up my clothes Scotty)


Tom Yoke says:
very small efficiency you name must presume an omnidirectional radiating antenna

That is incorrect – he presumes 20db gains for both Rx and Tx – which is 10x from omnidirectional.
It doesn’t matter whether you use maser or laser for power transfer – the path loss is always proportional of square of distance. It’s just with laser you can get very, very high antenna gains. But your very high antenna gain comes with extremely high directionality – and that means 2 things:
1. You need individual transmitter and antenna for every receiver and that transmitting antenna has to track receiver extremely well, as both beaming satellite and receiver move around.
2. You need receiver that has to track transmitter very precisely.

Stephen Richards

1st year étudiant ?

Tom in Florida

etudiant April 25, 2016 at 6:33 pm
“NASA in the 1980s did useful work on solar powered airplane concepts. One was based on a solar power satellite beaming power to the airplane. That circumvented the problem of low energy density provided by direct sunlight.”
I’ll bet the satellite didn’t get in orbit by solar power.


Batteries have been around for over 100 years. They aren’t in their infancy.
Solar power has been around for decades, it isn’t in it’s infancy.
Any technology that after 50 years is still stuck in the crib, is not likely to ever be useful.


..The delusions of the left wing “Greenies” is astounding..Solar Power has it’s uses in certain places at certain times…just like the batteries in my flashlight ! I wouldn’t want to try to use those batteries to keep me warm during the long cold Canadian winter nights !
P.S. I’m still waiting for Spring in London,Ontario !! 50 miles from the U.S. border !


Only Shania Twain can keep you warm on those long cold lonely nights 🙂


…OMG..Don’t tease ! LOL..Her voice could keep me warm in the middle of the Antarctic… naked !!

You not in a hurry, got a year to go from Hawaii to San Francisco, solar aircraft is the technology for you. You can even do some victory flights over the Golden Gate bridge to celebrate arriving alive.

Mike the Morlock

Donald Kasper April 25, 2016 at 6:40 pm
“You can even do some victory flights over the Golden Gate bridge to celebrate arriving alive.”
Not sure about that victory roll. To keep the weight down they had to make sacrifices. I got a feeling structural integrity was one of them. for example the weight for the shuttle carrying 747 was 488,000 pounds. (link below) An SUV which they compare the solar plane to is 4,000- 6,000 pounds. Try to do a barrel roll or an other acrobatics and the aircraft may come apart do to air frame stresses. Gravity,G-force, and all that other fun stuff.


Was that really a pro-solar PV PR stunt?
Or a secret pro-oil stunt? (sort of false flag attack, without the attack)

Barbara Skolaut


“I’m very happy that everything works extremely well and the airplane is functioning as it should,” Piccard’s business partner and the plane’s other pilot, Swiss engineer Andre Borschberg, told CNN by phone from California just ahead of the successful, on-schedule landing. “It’s a demonstration that the tech is reliable.”
Reliable? How long did this trip take, all up? A year or so? It’s “functioning as it should”??? Excuse me? A cargo plane flew with it every step of the way. Powered by fuel. Is this how it’s supposed to function, accompanied by a regular plane? That reminds me of so-called renewables running with full fossil fuel back-up. Try pulling the plug and see what happens.
As for the plane – No passengers, no cargo, it got delayed for ten months, it needed an escort and a hot air balloon can do it faster.
I’m so happy that “everything works extremely well and the airplane is functioning as it should”. I should hate to see how it goes if anything went wrong.


“A cargo plane flew with it every step of the way.”
Great startup costs don’t make a technology unworkable: it could be argued that when the solar plane is generalized, every airport will have its own landing bicycles and landing bicycle technicians will be on site. (The plane doesn’t have it’s own lateral gears and relies on bicycles.)
So the cargo plane crew is an artifact. The crew will be on site. The replacement parts too.
You can’t blame the coal pollution of the energy necessary to break, purify, transform rocks into yellow cake and then enrich uranium on the fission technology. In the end, fission energy can provide all the energy needed to enrich its own uranium. The coal pollution is just a startup cost. More fission means less coal burning pollution (sulfur, particulates, mercury, thorium, uranium…).

I don’t see “coal pollution” anywhere. Coal and oil and very clean energy sources now.
When aviation got going, planes went out on their own. If this one had gone out on it’s own, it’d still be stranded somewhere.
Why would they “generalize” solar planes? So far it hasn’t been able to carry anything except a light-weight pilot. Hot air balloons do it better and more comfortably and can carry more.
On it’s own this is merely an interesting toy – it is not the future and doesn’t promise a future until can actually function as something. It has to be able to work, meaning it has to be able to provide some kind of service.

You can’t blame the coal pollution of the energy necessary to break, purify, transform rocks into yellow cake and then enrich uranium on the fission technology.
No. But you have an end goal where the net return justifies the input. The cheer leaders for this technology seem to think that if we just invest time and resources, the technology will somehow advance to the point of being practical. Sorry, but even if the solar panels were 100% efficient AND weighed nothing AND were free, you STILL couldn’t build a plane that could carry people and cargo at a rate of travel that would be cost effective or practical.

France uses one nuke plant for enriching uranium.


Historically, France used only gaseous diffusion, an energy consuming approach: 3 nuclear reactors were needed to power the process! The new Georges-Besse II plant uses the much more efficient centrifugation separation process.

Gentle Tramp

“A cargo plane flew with it every step of the way.”
Not quite true. Actually TWO (!) fossil fuel powered planes flew with it every step of the way (see in the link of my first post above).
That is to say, they needed a big cargo plane for all necessary technical assistance material and one smaller passenger plane for the rather big ground crew and their luggage, and – last but not least – the luggage of the pilot! Not even the latter could be transported by this absurd green propaganda toy itself…

chris moffatt

We already knew that solar panels work in sunshine, that electric motors work when correct voltage is applied, that aircraft propellers work when they spin, that a big enough wing generates needed lift, that wheels work great for landing gear, that aircraft controls (ailerons, rudders, elevators, flaps) work to control an aircraft in flight. These things are proved every day. So what precisely is it that these folks have proved that we didn’t already know?


How silly some people are?


Would adding a very big wound up elastic band to the aircraft help?

Funny, I thought of that after I’d posted (above), only I was more thinking a giant ground-fixed catapult. Maybe the two ideas combined would actually help. 🙂


I fear the acceleration caused by a catapult might cause the lightly stressed wings to part company from the fuselage 😁

The obvious solution is a hydrogen filled Zeppelin with solar panels used to drive flapping wings.


That’s what I was going to say.
The Japanese got balloons to hit the US mainland back in WW2 using only the wind.
It would have been cheaper and more effective to use cutting edge renewable technology from 70 years ago than this solar folly.

Stephen Richards

It would have been cheaper and more effective to use cutting edge renewable technology from 70 years ago than this solar folly.
Like 400 yr old windmill technology ?

Owen in GA

Fill the Zeppelin with Helium, cover the top with solar panels to power the propellers and you might actually be able to travel wherever the wind blows you. Go against the wind, Captain? Sorry we haven’t the thrust.
Maybe if the passengers and crew all had those bicycle generator things and were forced to peddle in 8 hour shifts it would help?
Ooooh, I know, maybe an onboard nuclear reactor to power sufficiently large motors – that would do the trick.

Owen in GA

or even pedal in 8 hour shifts – I hate homophones.


” peddle in 8 hour shifts”
They are going to sell stuff to each other?


I was more interested in the pilot reporting seeing a plastic flotilla the size of continent.
What’s up with that?

Bruce Cobb

I saw that. But what he actually said was that he flew over it, not that he actually saw it. In other words, he “knew” it was there. Just like Warmists “just know” manmade warming is there, and dangerous.
Belief is now reality, and “science”.

As I understood it that “plastic flotilla the size of a continent” was actually garbage in some bay somewhere after a storm. An exaggeration in other words (or an outright lie).

Anthony brought us a really good essay/post/article on the floating plastic weeks ago. It simply does not exist. Like the “climate change” hoax it is a fund-raising idea by the watermelons. Plastic returns to CO2 in sunlight and air. Slowly in some cases, perhaps undesirably in some cases, but it just gets recycled by nature. Energy in and out and carbon bonds formed and broken is how the Earth system works in the main.
Like this solar airplane they love any story, particularly fiction, that demonstrates the “evil” of personal freedom and market freedom.

Does anybody know if this thing traveled west during the day and east during the night to maximize daylight travel?

My guess would be that it’s too slow to take that advantage.

I remember reading somewhere that some knowledgeable folks thought that railroad steam engines would blow up if they went 60 mph…. An there is that thing about Dick Tracy and his wrist radio….


Leading experts thought that if a train travelled more than 30mph that the passengers would all suffocate.
I believe it had something to do with the maximum velocity at which people could move air with their lungs.

And how much fuel and support was used to supply the plane on it’s trip?
I think it probably cost more in “fossil fuels” than a Charles Lindbergh used in his flight across the ATLANTIC.

I’m just saying that there was a huge support team…for this “solar” flight.

Exactly right. They just won’t mention that bit.


And they will just say it’s a first, and the cost of a first of a kind aren’t meaningful (including energy cost).
The problem is that unlike nuclear fission, costs will not go down after the first of kind.


My VW gets very good mileage drafting behind a large truck. Was the solar-powered plane drafting behind its fossil-fueled support plane?


I want to know if that contraption can fly in the other direction–without benefit of prevailing winds, or is “solar travel of the future” going to always be towards the rising sun in the N. hemisphere?


noaaprogrammer, I doubt the plane is strong enough to take the turbulence behind the support plane.


noaaprogrammer, I always draft behind a truck when possible (not usually practical in mountainous areas tho unless you can tolerate 50 mph up the grade). The increase in mpg is significant — at least a couple mpg.


Ha – it needs 100% fossil fuel backup, just like a wind turbine!

So this statement is essentially false: “An experimental plane flying around the world without a single drop of fuel landed in California after a two-and-a-half day flight across the Pacific.”
How much fuel did the 2 support planes use? You have to count that in, or this plane would have gone nowhere, other than the first leg with the first pilot.


Solar planes will never replace fossil fuel powered planes
how big a solar panel is required to generate the 115,000 lbs of thrust developed by each engine in a 777?
but of course the sunlight is free.

Russell Chapman

I haven’t seen a thing on the MSM about the enormous backup fleet following this thing around the world. They make it sound like he is doing a Kingsford-Smith or Lindbergh jumping into a plane and flying into the unknown.


A well rigged clipper ship would’ve done it far,far faster and carried people and cargo…
and without a “D” sail…

Gary Hladik

And of course sailboats are also 100% “solar”. In other words, it’s been done.


In 2012, a yacht circumnavigated the globe in 45 days 13 hours 42 minutes 53 seconds.

PV is not ready for prime time 🙂


Isn’t prime time after dark for most of the year?

bill johnston

Solar planes can fly to very high altitudes because they don’t need to burn oxygen with fuel for power. But they still need a certain density of air to support them. Not found at “very high altitudes”.

What about oxygen for the pilot? He can’t go too high because he can’t carry a tank.

Hats off...

And they require propellers for thrust. And the speed of sound reduces with altitude. At some point, assuming the propellers can still push enough air to remain at altitude, the propeller tip speed hits critical mach number.

Owen in GA

True, but we solved the supersonic propeller problem several years ago. The design just calls for a certain twist in the shape of the blades. Of course the shockwaves against the fuselage structures do tend to cause stress fractures and failures after a while.

Keith Minto

Exactly, it is a function of aircraft mass, drag, airspeed and air density.
“…airplanes have a flight ceiling, an altitude above which it cannot fly. As an airplane ascends, a point is eventually reached where there just isn’t enough air mass to generate enough lift to overcome the airplane’s weight. ” from
A high drag solar propellor powered craft with a low airspeed would have a low ceiling.

Lance Wallace

400 days and counting. Didn’t Phineas Fogg beat that record with 310 days to spare about a century ago?

Gary Hladik

I think that the wings should be less upswept, and have winglets. I think that would produce more lift with less drag. I base this just on the photo, I haven’t done any calculations, but it doesn’t look like that effecant of an airfoil to me.


It should’ve had 4 wings, not two: it would’ve been stronger, lighter, and easier to fly.

Steve Fraser

The handler bikes are on the wrong sides. The ‘red’ Penney belongs on the port wing, and the green one on the starboard.

Gary Pearse

This tells me that a nuclear plane is eminently feasible, and I am going to predict after they have decided to add lithium to the world’s drinking water to cure the brain lesion pandemic that has gripped the world, that in 50yrs we will have nuclear airplanes. we could have them in 30, but I added on 20yrs to be sure the hyper crowd has peacefully moved on because I just know they are looking into wind turbines for the next generation of flight technology. Solar added might be fine for on board LED lights and beer coolers.

each engine in a 777?
GE90 is 50 megawatts, or about 67,000 horsepower. Approximate unit price is $24 million
so, for 50 megawatts of power, with each solar panel putting out about 200 watts, you would need about 250,000 solar panels. 25+ million dollars worth of panels.
So, the solar panel is actually price competitive, the problem is the weight of 250,000 solar panels. The GE90 is something like 4hp/lb. Solar panels maybe 0.025 hp/lb. All the power is required to carry the panels.

David Chappell

Not to mention the area required for the solar panels.


Reliable? They fried the batteries on the Japan/Hawaii leg and had to raise $25million to replace them. It is really not even the same plane that started out $170mil ago.

Mike the Morlock

betapug April 25, 2016 at 7:50 pm
Hi thank you for the link I took this away from it.
“Two months’ delay meant the end of the circumnavigation for this flying season – the second Pacific leg cannot be safely flown after mid-August.”
So that is the real reason for the delay, can’t fly after August. Reliable??


Notice the pilots clothing, no heater I guess that would use up energy.


A friend of mine did a circumnavigation crossing the oceans in a rowing boat. His Pacific crossing was a bit faster than this flying machine.
Maybe we could provide everybody with an oar to generate power for travel.

Steve Fraser

Would that be an ‘exclusive OR’?


Did you know that if you take 3 oars and link them at the tips…
.. you get an E-oar. !


Well… There was a time when the US Air Force was thinking about designing a “Nucklar” powered intercontinental bomber…
That plane never did get off the ground…
This Solar plane did get off the ground, so we have to give them some credit for that….
But a year to go around the Earth ??? Really…… This is not a credible airplane with any real uses…
Like I’ve heard; “A Fool and His Money Are Soon Parted”, or something like that…
Cheers, KevinK

Gary Pearse

They’d be afraid to shoot that one down!


NB-36H had a few flights (40 something iirc) but it used the normal 6 turning 4 burning method of propulsion. pretty much only tested shielding on the reactor.

They didn’t even get around the Earth.

Kaiser Derden

besides the bragging rights why did they risk the lives of the 2 pilots when the plane could easily have been piloted remotely …?


Yeah the first James Watt engine was pretty useless too.
The depth of self-deluded thinking here is quite impressive. If you can’t see potential in this either you’re willfully ignorant or just lack imagination.


And the first electric motor (1830 first electric car) was pretty useless too.
However, putting the two together have developed into diesel electric. Now there’s a mobile power house if ever I’ve seen one.
There’s a whole area of being ‘fit for purpose’. This is a fun project and has no avenue for future development.


180 years later, the electric car is still pretty much useless.


Who told you Watts first engine was useless??

David A

evcricket, explain the potential for those here. Other then perhaps long duration remote surveillance, what do you see Do you see commercial flight capacity?


Actually, James Watt’s first steam engines worked pretty darned well. Of course, Watt’s engine was merely an enhancement of Thomas Newcomen’s steam engine, which had a number of drawbacks, among them losing power when the boiler cooled off too much. Watt’s external condenser solved that issue, among others.
But the Watt/Newcomen engines (and the generations of earlier designs) weren’t limited by some absolutely fixed maximum power, while solar powered airplanes ARE. Solar cells are nowhere near 100% efficient, but even if they approach that efficiency, they’re limited by the area of solar panels that can be deployed, and by the WEIGHT of the solar panels to be carried. And the weight of the batteries needed to keep aloft at night.
Perhaps someday, in some science-fiction future where solar power satellites can beam power via MASER to rectennas on the wings, it may be possible to construct “solar powered” aircraft capable of carrying some payload or passengers. But this is a stunt. A glorious stunt, but a stunt.

kenwd….your post is the second in this thread discussing beaming energy to the plane from space. Why not go all the way use a nuclear satellite and shoot the damn thing down with a proton beam weapon? More bang for the buck and truly at the frontiers of applied technology!


Precise beam control and collimation will enable to transfer enough power to make it fly, without transferring so much power to destroy it. Destruction is easy, especially if you have a MASER in GEO with sufficient power and skill to aim it. I want to provide more delicate power, CONTROLLED power.


Please tell oh omniscient one, what is the potential that the rest of us ignoramuses are missing?
Or are you just being offensive for the heck of it?

If you can’t see the limitations in this you’re willfully ignorant or just lack some understanding of basic energy density limitations and power to weight limits. These are not going away with just “imagination.” Solar is inherently a high weight, low energy density power source. Trying to make it work in applications that make no sense is not a breakthrough, it is just silly.
I recall the Mythbusters making planes out of concrete for their tv show. They worked about as well as this plane and not one person looked at that episode and “saw potential” in concrete as an aviation material! Why? Because as this solar plane shows, making aircraft out of heavy things is poor engineering.


Guiding a landing U2 would be more fun than a bicycle. High performance mustang used with the U2, raw dino powered horsepower.


“The plane took off from Hawaii on Thursday, resuming a journey that had stalled on the island of Oahu for almost 10 months.”
The flight had not “stalled” for ten months. It took that long to rebuild the airplane because it almost didn’t make it from Japan to Hawaii. It’s taken nearly a YEAR to get HALF WAY AROUND THE WORLD. Captain Cook could have done it that quickly, and a clipper ship could bring tea from China to London in only a couple of months.

charles nelson

You know if they’d called it a solar-power-assisted Glider, and pointed out that it was travelling with prevailing winds etc, I could have applauded their mad-cap achievement. But to present it as ‘powered flight’ is insulting to the intelligence.
If it looks like a glider, and averages 40 mph over a long trip…it’s a ‘glider’.

FYI, gliders don’t have propellers.


Earthling, stop being a smug know-it-all.

Mike the Morlock

indefatigablefrog April 26, 2016 at 12:08 am
Earthling, stop being a smug know-it-all.
Ha! your “Flak” caught me too.
Thanks for the link, good information. Now I know better.

charles nelson


Nice, friendly response from indefatigablefrog.


I guess they have not yet harnessed theBarsoomian Eighth Ray.

The plane took off from Hawaii on Thursday, resuming a journey that had stalled on the island of Oahu for almost 10 months.
You’d need a pile of meal vouchers on any commercial flight with a layover that long.

T Howell III

Be cool to fly solar, soon as I get my wife past the fact she has to pee pee through a hole in the seat.


I assume that no coal was burnt in the fabrication of the plane, and that no fossil lubricating oils were consumed, and that the support team did not fly on commercial airlines but used wind-powered yachts.

Before mocking any innovation, look back to see what was done previously.
In 1916, a few years after Bleriot flew across the English Channel in a single seater monoplane, a war was being fought that included biplanes and triplanes made mostly from wood and canvas using rotary engines.
Maybe solar powered flight will be the accepted form of transport in 2116, who knows?
For the record, I have my doubts, but in 1920, some people were wondering where all the horses would be stabled in the year 2000. Ö¿Ö


“Maybe solar powered flight will be the accepted form of transport in 2116, who knows?”
Isn’t this called argument from ignorance?
Actually, we do know that it won’t. Because whilst engine power could be scaled rapidly to suit the needs of propelling heavier and heavier aircraft across the sky on longer and longer journeys – we know that we can not increase the power of the sunlight falling on the upper surface of an aircraft in the same manner.
We can increase the efficiency of the panels towards over time. But never beyond unity.
So the fundamental physical limit will always exist.
Perhaps we can make these vehicles bigger and bigger and eventually carry a small crew and a handful of passengers on novelty flights – at extreme danger to all involved.
In which case we can look to history and see that the technology would be more akin to the development of the giant airships of the early 1900’s.
Only, more stupid and costly and probably less effective.


We can always add a really large lens to the plane :)))
Alternatively, we can use gravity generator to create gravity lens to focus light from much larger area.
Or we can use teleported at the sun to beam energy directly into the plane. Now that would really be solar powered!
And one mustn’t forget magic. There is always magic spell or to get sun to shine brighter on your plane.


Yes, these are extremely practical suggestions.
In fact, in the early years of the development of airplanes, it was common to use both the principles of engineering and magical incantations in order to successfully transport people through the sky.
Hence the expression “on a wing and a prayer”.
Of course, the political left are no longer interested in transforming the world via praying.
They will simply mandate that commercial solar planes must fly by passing a law to that effect.
The laws of physics must be conformed to the laws of man.

Who’s a smug know-it-all?


Well, it takes one to know one!!!
As long as everyone is having fun.
This is only a silly internet blog thread, after all. Nobody gets fined or assassinated!!

Flying from direct sunlight will never be suitable as that can’t provide enough power even not with 100% efficiency of the solar panels for any commercial flights. The only probable alternative is with batteries loaded with solar/wind/hydro/geo on the ground – if you like to fly “renewable” – or nuclear or fossil if it doesn’t make a difference for you…
The main problem then is the very poor ratio between stored energy and weight / volume, both important for long distance flights. It will cost a lot of research to get that substantially better. Only then such flights may have merit, as good as for 100% electric cars…


There are some who’s mind’s are so open, that their brains have fallen out.
All of the technologies being used here are quite mature. Where is the improvement going to come from to take this from a toy to a useful product?

“There are some who’s mind’s are so open, that their brains have fallen out.”
ha! great line!

Geoff Sherrington

Those props on shafts, those shafts would not be lubricated by OIL, would they, destroying the Utopian nobility of ‘no fossil fuel’? Maybe they have plastic bushes, but if so, no doubt the plastic was not made from natural gas or other fossil fuels.
It’s an expensive joke. No points for credible effort.

Matt Bergin

No need for fossil oil. They could have been lubricated with whale oil but somehow I can’t seem to picture the WWF or Greenpeace killing a whale and rendering the oil to use in their plane. 🙂

John in Oz
John in Oz

Sorry, should have left a comment with the above link.
Good spoof of electric cars (or anything else that is large, heavy and needed to move more than a grain of rice.
Is this a case of ‘First they make fun of us’ etc, etc “Then we win”? Probably not.



Stephen Richards

I just bought an SUV. I looked at the Mitsubishi PHEV. 50kms, if you are lucky, on batteries 1.9litres / 100kms. 30mpg on diesel. HTF is that saving the planet. My nearest town, of sorts, is 50kms. So I would have to drive to town, stay the day, come back before dark with a battery not fully charged if it was battery only car.
It’s a useless technology. Yes some time in the very distant future someone might come up with a battery solution for power but, hey, the energy density would need to be similar to FFs and charge time about 5 mins.

Matt Bergin

Stephen if they ever get a battery up to the power density of fossil fuels I would not want to be anywhere near it let alone sit on top of it inside a car. Batteries are very dangerous because they cannot be shut off. I maintain inverter power supplies at work and it is scary to work on large banks of batteries. Storage batteries have a very low internal resistance and will supply a huge current into anything that shorts out the terminals and this can lead to the battery exploding. I can not imagine how big the explosion would be from a shorted “fossil fuel” power density level battery bank. I think I will pass.

It’s good to see some of this stuff getting parodied in popular culture. It’s a welcome change from the ra ra hype of the late night comedians.


The crucial question about new technology is whether a breakthrough is required to make it work. If a breakthrough is required, all the money in the world might not be enough to bring about the technology. Our fearless leaders don’t understand that.
With current technology, electric airlinerss are impractical. We need a breakthrough in energy storage. I wouldn’t bet on it happening any time soon.
There is a book that everyone planning technology needs to read and understand:

In Why Greatness Cannot Be Planned, Stanley and Lehman begin with a surprising scientific discovery in artificial intelligence that leads ultimately to the conclusion that the objective obsession has gone too far. They make the case that great achievement can’t be bottled up into mechanical metrics; that innovation is not driven by narrowly focused heroic effort; and that we would be wiser (and the outcomes better) if instead we wholeheartedly embraced serendipitous discovery and playful creativity. link

In other words, breakthroughs happen when we stumble over them. They can’t be forced into existence.
Anyone who thinks this solar powered airplane presages solar powered airliners is living in cloud cuckoo land.
What will presage electric airliners will be the mother of all breakthroughs in energy storage.


“It’s a new era. It’s not science fiction. It’s today, It exists.” Piccard told CNN from California after his successful voyage.
And that was actually what he said when, upon landing, he was informed that former male athlete Caitlyn Jenner had won Glamour Woman of the Year.


The sheer industrial brilliance and generations of scientific might that have enabled solar tech to fly – awesome. Can you imagine how shocked solar worshippers would be if you lifted the sheet on the industrial might and public coin holding the whole edifice up.


We’ll probably end up with renewable powered planes at some point in the next few decades due to this obsession. We’ll probably end up using hydro, wind, solar and biomass to generate energy to create a fuel, which we will then load into jet engines.
Or maybe we will power some planes exclusively from bio-fuels.
And everyone will say – “see, they said it couldn’t be done. A “solar” plane.”
Boringly, this will almost inevitably happen in the current political climate.
Meanwhile, we will be ignoring that vast quantities of perfectly suitable fuel lie beneath our feet.
Or maybe in the future socialist utopia, only members of the U.N. will be allowed to use planes.
So that they can attend urgent conferences on “saving the planet”.


Could have gotten a clue from solar powered cars. I don’t think they’re very practical either. Everything that’s supposedly renewable sure seems to take up a lot of space. Wind turbines, solar, ethanol….we will have no place left to grow food.

Just as they had to re-invent the windmill and rename it “wind turbine” in order to try to pretend it was something new and any better than the old windmills that were rejected so long ago, so if you want “renewable” transport, then the obvious answer is the good old sailing boat … with the obvious draw back that its a lot slower, more expensive, prone to piracy, requires many more people and basically much more dangerous.
That is why they constantly try to replace the sail with some kind of “hi tech” device that is basically a sail, but gives the impression it is something new and will break the laws of physics and make wind viable.

Patrick MJD

I believe some of the America’s cup sail boats use a “fixed” type sail which is more like a wing from an aircraft and much more efficient than a typical sail.


Hi from Oz.. Thanks for your insightful post Scottish Sceptic. That triggered another thought – I wonder if the (real) mech and elec engineers that they must use to design stuff like electric cars and wind turbines have moments of ‘cognitive dissonance’ where they realise the intrinsic futility of their work, or are they such green ‘true believers’ that they can ignore reality indefinitely? Or maybe they are just doing it for the money…

Owen in GA

I think most of the engineers go into the projects knowing that the product is a political ploy, but have the integrity to try to make the vehicles as useful as the technology will allow.
Every real-world engineering decision is a compromise between cost and utility. There are certain safety bottom lines that can’t be crossed, but once those are covered, it is about making a product that will make the company money. Sometimes the product you design doesn’t make any money, but buys the company regulatory overhead to sell products that do make money. Thus you make a certain number of nearly useless electric vehicles in order to meet the CAFE standards to enable the sale of overpriced trucks and SUVs.


As an engineer, if I’m hired to build something, I will build it. The only time cognitive dissonance would come into play for me would be if the device I was building was for some kind of destructive purpose.
If the customer wants to waste his/her money, that’s the customer’s business, not mine.
If they ask my opinion, I will give them my honest opinion. If they don’t, then once again, that’s their business.

Ben of Houston

A lot of them get disillusioned in the cause. If they are doing it for the job, it’s nothing. However, if they think they are there to make a difference, then it’s frustrating beyond belief
I see the same with TCEQ employees. They go in thinking they are Planeteers and industry is evil, and then they end up issuing fines over incomplete paperwork and computer crashes. Some try and delude themselves that they are helping industry (permitting is the worst on this, as they often get the idea to “write permits for the common person” and come up with a result that is not easily usable by either expert or layman), but most others just get cynical and transfer to industry or private consulting.

michael hart

A single man crossed the English Channel to France in a human-powered aircraft 37 years ago. Imagine what could be achieved if all the greenies were forced to travel this way to their protests.
Heck, they could even go to conferences in cold dark places where solar cells don’t work.

Richard of NZ

Even more interesting is the fact that the aircraft used, Gossamer Albatross, evolved into the Gossamer Penguin which was solar powered. A even later development, Gossamer Challenger also solar powered,flew from Paris to Manston.
It seems that little progress has been made in the past 30 odd years. The first round the world flight by conventional aircraft occurred in 1924, just 21 years after the brothers Wright first attained controlled powered flight. It would appear that development of solar flight is happening much slower than technologies that had some actual, as opposed to theoretical, potential.

Phileas Fogg would not feel threatened.