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Solar-Powered Boat Carries 8.5 Tons of Lithium-Ion Batteries
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."
Wouldn't it be cheating if he rows across the ocean in a solar-powered boat?
Do not look into laser with remaining eye.
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?
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.
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."
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.
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.
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.
A Hindenburg that floats.
Um, airships do float.
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.
I am going to hack the shit out of him once I finish pwnzoring 127.0.0.1
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.
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.
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?
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.
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.
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.