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Solar-Powered Boat Carries 8.5 Tons of Lithium-Ion Batteries

Posted by Soulskill on from the solar-powered-submersible-still-facing-engineering-challenges dept.

bshell writes "The Verge has a great photo-essay about Tûranor PlanetSolar, the first boat to circle the globe with solar power. 'The 89,000 kg (nearly 100 ton) ship needs a massive solar array to capture enough energy to push itself through the ocean. An impressive 512 square meters (roughly 5,500 square feet) of photovoltaic cells, to be exact, charge the 8.5 tons of lithium-ion batteries that are stored in the ship's two hulls.' The boat is currently in NYC. Among other remarkable facts, the captain (Gérard d'Aboville) is one of those rare individuals who solo-rowed across both the Atlantic and Pacific Oceans, journeys that took 71 and 134 days, respectively. The piece has a lot of detail about control systems and design."

36 of 164 comments (clear)

  1. Isn't that cheating? by TWX · · Score: 4, Funny

    Wouldn't it be cheating if he rows across the ocean in a solar-powered boat?

    --
    Do not look into laser with remaining eye.
    1. Re:Isn't that cheating? by PPH · · Score: 5, Funny

      No. Cheating would be poking a hole in the back of the battery packs, waiting for the seawater to hit the lithium and taking off like a rocket.

      --
      Have gnu, will travel.
    2. Re:Isn't that cheating? by davester666 · · Score: 2

      He bitch-slaps Popeye every day right after he has breakfast.

      --
      Sleep your way to a whiter smile...date a dentist!
    3. Re:Isn't that cheating? by necro81 · · Score: 2

      This is a giant leap into stupidity

      Of for fuck's sake: lighten up! If you had read the article or any other news related to this project, you would know that the creators of the boat aren't looking to pioneer a new mode of transportation. They all recognize that sailing is a much more effective way of having a "solar-powered" boat. The makers of the Solar Impulse airplane aren't trying to replace commercial aviation, either. These are technology demonstrators, like multi-million dollar concept cars; they don't have to be practical or ready for wide adoption.

  2. What Bat Villian designed this boat?!?! by Picass0 · · Score: 2

    Saltwater and batteries!?!?!

    1. Re:What Bat Villian designed this boat?!?! by BrokenHalo · · Score: 2

      Seems to me that 8.5 tonnes of batteries would take more energy to drag across the water than it was worth. Meanwhile, of course, people have been using sails for centuries to get around the globe.

      There are good reasons to use the lowest tech required to do the job. Sure, they be trying to make some sort of point, but I'm sure there are more useful ways to do that.

    2. Re:What Bat Villian designed this boat?!?! by viperidaenz · · Score: 3, Insightful

      How much oil would it take to move a boat round the world? I would say 8,500kg of batteries isn't a lot for a 100,000kg boat.

    3. Re:What Bat Villian designed this boat?!?! by JanneM · · Score: 4, Insightful

      Most ships need ballast anyhow. Not clear that there's any net weight penalty at all from carrying the batteries.

      --
      Trust the Computer. The Computer is your friend.
    4. Re:What Bat Villian designed this boat?!?! by Tastecicles · · Score: 3, Informative

      square hulls don't require ballast, they're stable by nature of the shape. Neither do catamarans or trimarans, they're stable for much the same reason that square hulls are: edge displacement equals or is greater than centre displacement.

      An ASCII demonstration:

      \/ : single-keel trangular hull. Not very stable because at each point on the hull a different upward pressure acts, resulting in something that requires ballast in the bottom to keep it pointed the right way and/or....
      Y : triangular hull with sail. Only stable because of the sail (which has ballast in it). Without it, it's about as stable as a log in white water.
      \_/ : still a triangular hull, this time with a double keel. More stable than the single keel (above), but think of the small rowboats one would use on a lake. Obviously the wider the hull in relation to the length, the more stable it's going to be, but it ain't gonna be capsize-proof. Would still require ballast if it's doing anything other than glass-still laking.
      |_| : square hull. Very stable because the same upward pressure acts on every point of the hull bottom. Wider=capsize proofing. If you could make a double wardrobe watertight, it would be brilliant as a rescue/evac boat in case of disastrous flooding, because it would hold as much human weight as the total volume of water displaced (40 cubic feet to an inch of the side, for argument's sake, that's 1.13 cubic metres - that's over a ton of water, or a dozen to fifteen full grown adults) and still be rock solid stable.

      --
      Operation Guillotine is in effect.
    5. Re:What Bat Villian designed this boat?!?! by PopeRatzo · · Score: 5, Insightful

      Seems to me that 8.5 tonnes of batteries would take more energy to drag across the water than it was worth.

      Striking that in a community of self-identified "geeks" and "techies" that the notion of "proof of concept" would be so difficult to grasp.

      "Big deal, they walked around on the moon, but they had to wear big heavy protective suits to do it, so clearly, we shouldn't have a space program. And so what that the Mars Rover is tooling around on the surface of Mars. It moves really slowly so we shouldn't do any more Mars exploration until we can bring a Ford Explorer and get around like Jesus intended, with internal combustion engines burning refined oil."

      Here's a group that will embrace any new technology, stand in line to buy an Apple iWristwatch, but the mere mention of anything having to do with research into energy from any source besides Big Oil, Big Coal and Big Nukes and they dig in their heels like somebody's trying to take away their binkie.

      Sometimes I'm surprised they're not holding out until their laptops can run on a two-stroke engine.

      --
      You are welcome on my lawn.
    6. Re:What Bat Villian designed this boat?!?! by fauxjargon · · Score: 2

      It has two hulls which contact the water under normal conditions. The reason the middle hull is nicely shaped like that is so that in rough seas, when water does hit it, it deflects more gently off the sloped sides rather than slamming into a boxlike hull.

    7. Re:What Bat Villian designed this boat?!?! by dywolf · · Score: 3, Informative

      you're only correct if youre talking about a hull riding smack on the surface and not extending beneath it. ie, you're ignoring CG, displacement, and actual bouyancy dynamics and vastly oversimplifying the problem.

      the bouyancy forces acting on a hull dont care if they are acting on the angled side of a V hull or the flat bottom of...well a flat bottomed boat.

      the surface area of the horizontal plane of the boat hull where it intersects the waterline is effectively a "flat hull", or the "area upon which the bouyancy forces act", for any boat, regardless of whether the hull is a perfect square or a perfect circle or inverted triangle.

      two hulls with different shapes but the same surface area of that plane (and the same displacement and CG are equivealent) will have the same bouyancy forces acting upwards on the hull.

      --
      The guy who said the election was rigged won the presidency with the second-most votes.
    8. Re:What Bat Villian designed this boat?!?! by dywolf · · Score: 2

      also: catamarans are "not stable for the same reason that square hulls are". that statement alone shows a basic misunderstanding of boat design and simple physics/statics.

      a catamaran is stable because if you imagine one side unsupported (such as a wave dropping out frm under it) you have a CG which extended beyond the vessels "base", ie, the remaining outrigger. this causing a natural tipping moment until the unsupported outrigger comes into contact with teh water again.

      --
      The guy who said the election was rigged won the presidency with the second-most votes.
    9. Re:What Bat Villian designed this boat?!?! by aaarrrgggh · · Score: 2

      The boat is interesting, but to me mainly in the sense of where hybrid-electric propulsion can go. PV is a fairly impractical choice for 100% of power, but showing it as possible moves the state of the art further. The lithium batteries would scare the shit out of me though in the middle of the Atlantic. Sure you can have fire suppression and you have at least two independent strings... which is arguably more redundancy than a sailboat with one mast and no engine... But...

  3. Net Energy Use? by Anonymous Coward · · Score: 3, Insightful

    Anyone have an estimate of how much energy it takes to produce and transport 17,000 pounds of lithium ion batteries?

    Is this really an efficient solar use compared to, say, sail?

    1. Re:Net Energy Use? by fox171171 · · Score: 4, Informative

      Anyone have an estimate of how much energy it takes to produce and transport 17,000 pounds of lithium ion batteries?

      Is this really an efficient solar use compared to, say, sail?

      Moving heavy loads by sea is very efficient. You don't see "container-planes" for a reason. The buoyancy from the displaced water does the lifting, you just move it.

    2. Re:Net Energy Use? by Tastecicles · · Score: 2

      the technology's there, why not use it? Why not use *both*, indeed?
      As someone else has already pointed out, you don't need to lift the load in water, the water does that: the vessel finds a point where its mass equals the mass of water displaced and there finds a neutral buoyancy. All you need to do then, is push it with enough force to overcome hydrostatic friction and send it on its way. 10% of an oceangoing vessel for fuel is a stupendous amount of deadweight. Most tankers have *tiny* fuel tanks - often less than 1% of the deadweight.

      Lifting a mass into the air, ever a paltry 32,000 feet (pretty much what heavy haul cargo eg mail does) requires a huge amount of energy. Half an intercontinental airliner's mass at liftoff is fuel. That's how inefficient it is. Take it to the extreme: the amount of energy needed to put a 1kg satellite into orbit would power an average American home (2 adults, 2 children) for six hours. Then you have to factor in the energy needed to lift that fuel and the rocket from a dead stop to 17,000mph in four minutes. Then multiply that requirement by the total mass of the rocket plus payload. Sixty eight tons of shuttle, eight tons of satellite suddenly seems like a ridiculous proposition. The problem is solved by dedicating most of a launch vehicle to fuel. In the case of the shuttle system, that figure runs 729 tons - 99% of the total weight on the pad. Most of that will be gone in the first ninety seconds.

      --
      Operation Guillotine is in effect.
    3. Re:Net Energy Use? by KGIII · · Score: 3, Insightful

      I am hoping that you know this but I am compelled to respond to your post. I feel like I'm potentially preaching to the choir here but, well, it could be possible that you don't know this. If you don't then, well, I feel sad for you but not in a bad way. The quote is pretty common... The quote is also usually finished with a statement about how the USSR just used a pencil.

      The reality is that NASA didn't develop (or pay for the development) of the space pen at all. It was developed by Fisher, at their own expense, and with no guarantee that it would be purchased by NASA for use in space. What had happened was that NASA had paid way too much money for some mechanical pencils and the public found out about the expensive pencils and all hell broke loose. Keep in mind how much we were spending on the space race at the time, be sure to convert those dollars to today's dollars for a true comparison. Americans were well and truly pissed and justifiably so.

      Citation

      What the above link sort of touches on is the trouble with the idea of using a pencil, which is something you hadn't mentioned at all but I'll bring it up in order to be complete. One of the reasons that I understand a pencil is a bad idea (while sort of mentioned in the article they don't go into in at any depth and don't cover this specifically) is that every time you write there are microscopic fragments of graphite that break away. In a weightless environment they can go all over the place and graphite is also a very good conductor of electricity. The various electronics were very sensitive at the time and while most systems had a backup any point of failure was seen as a bad thing. The small bits of graphite could conceivably float away, enter a computer system, and cause a short - which wouldn't necessarily result in a fire but could possibly be a Bad Thing® and *could* potentially cause a fire in and of itself. (I'm not sure how well pencils themselves burn or how much the flammability of the pencil itself was a concern that actually was for NASA to be honest.)

      That is, as near as I can remember, how the story was relayed to me by someone who worked on the earlier Apollo missions. The conversation was over more than one beer (and about a lot more than that) so I may have missed something. The linked citation pretty much goes along with the story as he detailed it.

      If I may digress a bit... I was not alive for the earliest launches but I do recall watching the first humans on the moon on television. My parents told me the cliché about how I could do that someday but I never really wanted to walk on the moon. It did change me though. It made me interested in the technology and the computers that got them there. I didn't want to walk on the moon but I did want to work one of those giant beeping machines with the interesting dials and gauges on the ground and maybe visit space for a little while just to experience weightlessness but I wouldn't want to stay there for long. Not every little boy wanted to be an astronaut when we grew up, some of us wanted to play with the machines that went beep instead. And, well, that was me. I never did get to play with NASA's beeping machines but I've was in front of a computer for pretty much all of my professional life and still sit in front of one now that I'm retired.

      --
      "So long and thanks for all the fish."
  4. Re: Same guy who made every car, plane and trains by Anonymous Coward · · Score: 2, Insightful

    Flammable fuel in an oxygen rich atmosphere?!

  5. Re:This is stupid by __aaltlg1547 · · Score: 2, Informative

    I'm sorry but this is complete nonsense.Francis Chichester sailed around the world under solar power in 1966. I suspect it was a lot "greener" to build his boat that this. No wonder Jeremy Clarkson talks about the "green monster"

    Ferdinant Magellan did it in 1520. (Wind power is solar power, conveniently converted to a form more amenable to pushing ships.)

  6. vs. Wind Power by tirerim · · Score: 4, Insightful

    Of course, wind powered boats have been circumnavigating the globe since the 16th century, and can be faster, too. So this is interesting, but not exactly that impressive as a demonstration of eco-friendly sea travel.

    1. Re:vs. Wind Power by __aasqbs9791 · · Score: 2

      Storks that got lost?

    2. Re:vs. Wind Power by AmiMoJo · · Score: 2

      It may well be easier to integrate into large transport ships though. Something like an oil tanker has a large surface area that could be covered with PV panels and provide extra propulsion to supplement the diesel engines.

      Also sails don't provide any electrical energy, which in some applications (e.g. floating laboratory, drone boat) could be very useful.

      Why is it that on Slashdot if any new technology doesn't replace all existing ones in every imaginable application for very possible user it must be worthless?

      --
      const int one = 65536; (Silvermoon, Texture.cs)
      SJW, n: "Someone I don't like, and by the way I'm a fuckwit" - AC
  7. Re:Why the stupidity by lobiusmoop · · Score: 3, Funny

    Clearly they were working on a fishing vessel to go out trolling for engineers. (And quite successfully too it seems)

    --
    "I bless every day that I continue to live, for every day is pure profit."
  8. Re:This is stupid by mmontour · · Score: 5, Informative

    Ferdinant Magellan did it in 1520.

    No, Magellan only made it as far as the Philippines and then he was killed. It was Juan Sebastian Elcano who completed the voyage.

  9. Re:This is stupid by BrokenHalo · · Score: 2

    Francis Chichester sailed around the world under solar power in 1966.

    Yep, and his account of it is worth reading. But circumnavigating the world was hardly new even then. He was simply the first (and fastest) to do so single-handed via the clipper route.

    Captain Joshua Slocum's earlier single-handed circumnavigation wasn't non-stop, but his account of it ( Sailing Alone Around The World, 1900) is truly inspirational.

  10. Re:Alternative technology? by quenda · · Score: 3, Funny

    But what if you wanted to move into the air current? You'd have to wait for the direction to change. It'll never catch on.

  11. Re:Very nice by lkernan · · Score: 5, Funny

    A Hindenburg that floats.

    Um, airships do float.

  12. Wattage by Dan+East · · Score: 3, Insightful

    The thing I was most curious about was the total wattage the solar panels can produce: 93,500 watts. It takes 2 days to charge the lithium batteries even at 93.5 kW.

    --
    Better known as 318230.
  13. 10.3.250.11 by TsuruchiBrian · · Score: 3, Funny

    I am going to hack the shit out of him once I finish pwnzoring 127.0.0.1

  14. Suboptimal by ATestR · · Score: 2

    I saw this in the news last week... I didn't think at the time to question to weight of the batteries, but it occurs to me that using a catamaran design is suboptimal. You might as well go with a monohull, and design it around the batteries as ballast.

    --
    âoeAny society that would give up a little liberty to gain a little security will deserve neither and lose both.
    1. Re:Suboptimal by Tastecicles · · Score: 2

      that is a buttload of deadweight for a boat.

      --
      Operation Guillotine is in effect.
  15. Re:This is stupid by __aaltlg1547 · · Score: 2

    Ferdinant Magellan did it in 1520.

    No, Magellan only made it as far as the Philippines and then he was killed. It was Juan Sebastian Elcano who completed the voyage.

    That's true. And it did take 3 years to finish the voyage. They actually got back in 1522 (those few who made it all the way). However, people sail around the world in sailboats almost routinely now, in under a year.

  16. 20 HP average? by k2backhoe · · Score: 3, Interesting

    This has 512 m^2 solar array, incoming sun at directly overhead is roughly 1 kW / m^2, assume solar panel efficiency of 15%. This is a total power of about 76 kW or about 100 HP when the sun is directly overhead. Averaged over a 24 hour day, this is maybe 20-25 HP. 89,000 kg of lithium battery at 200 Wh / kg is 17.8 MWh. This would take 234 hours to charge with the sun directly overhead. That is about 40 days of clear sky charging, assuming you are not running the propeller at the same time. Something is fishy here. Sounds like he charges in port, then runs to the next port on solar plus battery (otherwise there is no need for this large battery / solar cell ratio). Then he repeats. Is my math wrong, or is this story a bit strange?

    1. Re:20 HP average? by starfishsystems · · Score: 2

      Directly from TFA:

      Length: 31 m Width: 15 m Height: 6,30 m Draft: 1,55 m Weight: 89 t Average speed: 5 knots (9.25 km/h) Surface area of solar modules: 516 m2 PV panel efficiency: 18.8% Installed PV power: 93.5 kW (127.0 HP) Maximal engine power: 120 kW Average engine consumption: 20 kW (26.8 HP)

      Your figure of 89t refers to the total ship weight, not battery weight. Your calculations are out by an order of magnitude. The claimed recharge time is two days.

      --
      Parity: What to do when the weekend comes.
  17. alternative energy by stenvar · · Score: 5, Funny

    We should be investigating the use of wind energy for moving ships. Perhaps there is some way (probably very complicated!) in which we could avoid converting the wind energy to electrical energy before converting it into propulsion. I have a feeling we might be able to create some zero emission ships that way.