Solar Impulse 2 Is Chilling In Hawaii for 2–3 Weeks (Video)
Originally published on 1Sun4All.
In the latest news from Solar Impulse 2 (Si2), the team says that, despite having completed the longest and most difficult leg of the round-the-world solar flight — the record-breaking oceanic flight of 5 days and 5 nights (117 hours and 52 minutes) in a solar-powered airplane — the record-breaking aircraft of Bertrand Piccard and André Borschberg has suffered battery damages due to overheating and will undergo maintenance repairs on the batteries.
During the first ascent on day #1 of the flight from Nagoya to Hawaii, the battery temperature increased too much due to over-insulation. And while the Mission Team was monitoring this very closely during the mission leg, there was no way to decrease the temperature for the remaining duration of the flight, as each daily cycle requires an ascension to 28,000 feet and descent for energy management issues.
The damage to certain parts of the batteries is irreversible and will require repairs and replacements that will take several weeks to work through. In parallel, the Solar Impulse engineering team is looking at various options for better management of the cooling and heating process for very long flights. Si2 does not see the possibility for any flights before 2–3 weeks at the earliest.
While you’re waiting for leg 9 of this round-the-world attempt, you may want to check out the new websites for the pilots and founders of this amazing adventure:
- Information on Solar Impulse’s chairman and co-founder Bertrand Piccard, is available at: bertrandpiccard.com
- Information on Solar Impulse’s CEO and co-founder André Borschberg, is available at: andreborschberg.com
If no one tells you it’s impossible, it means you are not ambitious enough pic.twitter.com/W7njYNxYKw
— Bertrand PICCARD (@bertrandpiccard) July 11, 2015
Si2 is attempting the first ever round-the-world solar flight to inspire innovation and pioneering spirit and encourage the adoption of clean technologies, renewable energy, and energy efficiencies. You may want to check out the cool Paper Plane Campaign video. Having started in Abu Dhabi in early March, Si2 has completed 8 legs covering nearly 18,000 km (11,185 miles) thus far in its around-the-world journey.
It is anticipated that Bertrand Piccard will fly the next leg to Phoenix (estimated distance 4,707 km, 2,925 miles, estimated time 3 days) before the mission continues onward to New York, Europe, and Abu Dhabi where it all started.
Join the Movement: FutureIsClean.org #FutureIsClean
————+—+——Si2——+—+————
FYI: After the original Solar Impulse prototype, which holds 8 world records, Si2 engineers designed and constructed the new single-seater aircraft made of carbon fiber. It has a 72 meter (236 feet) wingspan (larger than that of the Boeing 747) for a weight of just 2,300 kg, (5,071 lb), equivalent to that of a car. The 17,248 solar cells built into the wing supply electric motors (17.5 CV each) with renewable energy. The solar cells recharge four lithium-polymer batteries totaling 633 kg each, which allow the aircraft to fly at night and therefore have virtually unlimited autonomy.
Photo, Video, and Cartoon Credit: Solar Impulse
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Amber . . .
Thanks for your ongoing reports on Solar Impulse 2. I generally find them well written and concise. My only criticisms is that you post your reports and never respond to reader questions, perhaps not ever checking back to even read the comments. Other writers here on Clean Technica are far more proactive in this regard.
Why I bring this up now is a long and ongoing series of questions I’ve posted to your Solar Impulse 2 articles – ever since you started logging them here – asking you for detailed information on the batteries (ie: specifics on cell chemistry and, no, simply saying “lithium ion” is essentially a non-answer.)
Please do some sleuthing for us and get in touch with someone at Solar Impulse who can really explain the details regarding cell chemistry, pack assembly, etc.
Thanks again . . .
You could ask as well for the time 🙂
Try the search engine or the PV-press:
“The batteries were developed with Solvay, Kokam and Bayer Material
Science, and have been optimized to 260 watt hours per kg. Combined,
they can store 164,580 watts of power, and weigh 633 kg – one-quarter of
the aircraft’s total weight.”
Read more: http://www.pv-magazine.com/news/details/beitrag/solar-impulse-grounded-following-irreversible-battery-damage_100020176/#ixzz3fnsWYmaP
As you can read in the article they’ll have to be replaced. If they use a new type or the old one might still to be decided.
The control center in Monaco might be able to sort you out.
Nope . . . not the answer I’m looking for! Those pack statistics were taken from a years-old press release and have appeared in many previous articles. Since we don’t know the Amp hours of the packs or the voltages of the cells (multiply the two to get the Watt hours statistic provided) we really haven’t learned anything new. Boilerplate stuff. Nothing new.
Actually, heinbold, I have attempted to ask Solar Impulse directly, via one of their (too many) numerous blogs on their own expansive web site. Alas, no answer. My guess is they’re all rather busy and my comment is one of too many for them to parse. It’s also probably a bit too technical for the people who monitor those blogs to answer . . . easier to ignore than to get up from the chair and find someone who could provide the real answer. I will ask their technical people in person when they get to Phoenix (I’m only 100 miles away, in Tucson, and will be driving up there when the plane arrives.)
Also, I’ve inquired elsewhere on the web and, by sheer coincidence, found an earlier article on the PV Magazine web site that contained what I observed to be the most informative article on the plane so far (it was here that I finally learned that SI2 uses DC motors, which was another ongoing question I had) and, yes, I left a comment that has yet to be answered) . . .
http://www.pv-magazine.com/news/details/beitrag/we-have-lift-off–solar-impulse-begins-round-the-world-journey_100018506/#axzz3beNB2Eai
I’m looking for something that resembles a collection of words or acronyms of the individual chemical elements, such “lithium titanate oxide” (Li2TiO3) or “lithium nickel cobalt aluminum oxide (LiNiCoAlO2) . . . battery chemistry!
I tend to thing it’s not classified information but, since it isn’t included on official press releases, the typical journalist with little or no technical background doesn’t think to actually ask the question.
Also . . . I find it highly doubtful that the Solar Impulse ground crew will suddenly drop in another battery chemistry (possibly having to intermingle old cells or packs with new) at this critical stage. What is known is that the packs are sealed in an insulating foam cocoon and that this probably exasperated the overheating. My guess is – after replacing any defective cells or packs with new ones of the same type – they’ll work on some sort of better air cooling scenario. This only makes sense, as they are about to fly into the hottest part of the U-S during the hottest part of the year.
A fantastic project, chapeau!
Another one for the smaller pocket, watch the video:
http://oekonews.at/index.php?mdoc_id=1100181
At 0:50 the pilot found the manual.
It looks like flying a Solex, that is French engineering! I love it 🙂
https://www.youtube.com/watch?v=BWwoOW1d2EM
The Solex 2200 reminds me of a motorbike in an antique car museum up in NY. It is powered by an Evinrude outboard boat motor from back in the 1920’s with water circulation through a radiator system to keep from over heating.
As it was found in an old barn back in the 1990’s they are unsure if it was just a one off built by an individual or was part of a regular production. The assembly quality seems to indicate the latter, but no other historical reference about it has ever been found.
Surprisingly when found in the barn it was still able to be run and operated,before being donated for display.