[frankthetank]

This may have been discussed before, but this is my first time seeing it.

Couple of things i would do different. Not sure why they choose lead acid? Probably cost. I would go Lithium Ion or the LiPO. You'd cut the weight tremendously, plus you could almost be sure to move that barge faster. Doubling the speed would be my first goal. 4 knots isn't that impressive. A sailboat could have beat this thing bad. 5 guys on this one boat seems an overkill. You would think 2 could have handled it, once again reducing weight. I still think a small sail of some sort maybe could be design in? Or what about at least a wind generator? Windy days could then charge the batteries. Very cool trip, can read the blog entries and watch videos at the link at the bottom of this post.

I really can't see this being anymore "unreliable" then a normal sailing vessel. Electric motors/batteries? Can't get more simple then that.

The "sun21"

The boat is called "sun21". It is a catamaran of the MW-LINE Type C 60 and it is similar to the boats used at the Swiss National Exposition Expo 02. The boat is about 14 m long and 6.6 m wide. It sleeps 5 to 6 persons for the long journey across the Atlantic and has room for large groups for visits or short excursions. The kitchen is placed in one hull and sanitary installations in the other. A large deck roofed with photovoltaic modules has been installed between the hulls. The boat is equipped with solar modules, batteries and motors allowing a constant speed of 5–6 knots (10–12 km/h) 24 hours a day, equivalent to the average speed of sailing yachts.

"sun21" makes historic arrival in NYC!

Using solar power only, the catamaran "sun21" undertook the first motorized crossing of the Atlantic with solar power to promote the great potential of this technology for ocean navigation. The "sun21" arrived in New York City on 8 May 2007, 3 pm, having covered about 7000 sea miles. The journey of sun21 was made possible by the association transatlantic21. After the activities in New York, the association donated the solar boat to the WWF Adena/Madrid who will use it as scientific research vessel.
Recently, the crew of the sun21 was awarded by the Guinness World Records for the fastest transatlantic crossing made completely under solar power.
At the moment, the boat still lies to anchor at the harbour, waiting for authentication of the Spanish maritime authority.

http://www.transatlantic21.org/

[steam_cannon]

Solar ships are pretty cool and totally automated robot ships would
be even cooler. Now days I kind of question how sustainable
anything solar is due to the rare metals required, but aside from
that it's definitely a cool application of technology.

Couple of things i would do different. Not sure why they choose
lead acid? Probably cost. I would go Lithium Ion or the LiPO.
You'd cut the weight tremendously, plus you could almost be sure
to move that barge faster.

Not necessarily, it's handling characteristics might be a lot better
with the extra ballast keeping the ship stable. And the ship may be
better at maintaining a constant speed though conditions with large waves.

5 guys on this one boat seems an overkill.

Yeah the only think they were missing was MaryAnn and an island
to get stranded on

But seriously, if they were trying to demonstrate the reasonableness
of using solar for travel on the seas, the more the merrier.

[frankthetank]

That is true about the ballast, although you could put in the same amount of a "newer" battery tech and have that much more capacity... I like the idea of two separate motors. One fails, and you still have one.

I know what you mean about solar. I don't think it solves any of our major problems, but in some situations, it is the best way to go. (remote installations)

This boat would have major problems in the northern areas of the Pacific/Atlantic. Only probably good in tropics or inland lakes, rivers in the summer.

[steam_cannon]

I like the idea of two separate motors. One fails, and you still have one.

Oh I don't know, one motor might not be so bad...

The Captain: Sorry MaryAnn, the one motor failed, ahh and the one radio too. I guess
we'll be stuck here until the professor can fix it.
MaryAnn: Ever play twister with coconuts?
The Captain: