Full Solar Powered Boats

[jag2501]

I know wind sailing is a blast, power boats are not for me, but there are Solar boats out there that get very little attention.

From an electronic point of view with maintenance included it seems a real bargain. Used Tesla batteries from Ebay, Solar panels in California are quite cheap. Of course a generator would be on board.

From an excitement point of view it seems a bore. The commercial solar yachts are capable of a 24 hour cruising speed of 6.1 knots with burst speeds of 10 knots and at 6 knots average a day that's 144 nautical miles a day.
http://www.yachtemoceans.com/solarwa...la-on-the-sea/

I'm seriously interested in building a retrofitted solar boat out of a power catamaran, but why do I seem to be the only one?

[StuM]

This should be fun.

[StuM]

OK, I'll kick it off - any links to one of these "commercial solar yachts"?

[dwedeking2]

Of course a generator would be on board.

Doesn't this make it not "full solar"?

[Paul Elliott]

Here's one:

Solar power: ingenious solutions for boaters - boats.com

I'm not trading in my diesel-auxiliary sailboat though...

[Cotemar]

Solar boats work, but they are very expensive and most are built to set records and educate people as to what’s possible. Not really the ideal cruising boat.

The Sun 21 Solar Boat

The "sun21" was awarded by the Guinness World Records for the fastest transatlantic crossing made completely under solar power. In 29 days, the "sun21" crossed the atlantic ocean from Las Palmas, Gran Canaria to Le Marin, Martinique in February 2007. The boat is about 14 m long and 6.6 m wide.
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.

[ranger58sb]

Originally Posted by jag2501

I'm seriously interested in building a retrofitted solar boat out of a power catamaran, but why do I seem to be the only one?

Lots of threads around here about electric-powered boats, with solar often considered a major factor. Many of the pros and cons -- and other assorted challenges -- have been discussed. Read those bazillion posts... and then go for it, if you like.

-Chris

[GordMay]

Greetings and welcome aboard the CF, jag.

[valhalla360]

You aren't the first. There are lots of threads with people hoping to overcome the physics involved.


Your link didn't fully work so I couldn't check the underlying stats but I am very skeptical of 6kts continuous for 24hrs per day.


If you can put together a full solar (not generator) boat for the same price as a diesel powered boat and get that kind of performance, you just killed the diesel motor market and probably the sailboat market (my belief is most sailing cruisers do so as a means to an end not because they prefer sail).


If you do a search on electric propulsion on the forum, the numbers have been run many times and no, you aren't going to produce that kind of speed from a typical cruising boat without spending significantly more up front and burning a lot of diesel with a generator that is overall less efficient.


Solar is great for cutting back on the need for electric to power house loads but propulsion demands are too high to match what a diesel can do. Even then without a huge solar array and battery bank, even air/con is tough to do with solar.

[sagablu]

Since the wind is powered by convection related to solar energy, are all sailboats solar powered?

[valhalla360]

Originally Posted by sagablu

Since the wind is powered by convection related to solar energy, are all sailboats solar powered?

By that definition, just about any power source with the possible exception of geothermal is solar powered.

Dino-juice is just stored solar energy from millions of years ago.

[Mike OReilly]

A few years ago I met a 40+ foot catamaran fellow through CF that had converted his engines to electric. Still had the sail, but had covered his coachhouse and some deck area with solar panels. Seemed like an interesting idea.

Unfortunately this cat was a home-built ferro-cement boat. He was a cement guy so everything inside was constructed of cement. It seemed way too heavy to move, let alone sail.

GordMay, remember this guy?

[bobnlesley]

Originally Posted by StuM

OK, I'll kick it off - any links to one of these "commercial solar yachts"?

A friend of mine Skippers this one:
Solar Heritage | Chichester Harbour Conservancy

though I gather it needs plugging into the mains-supply regularly during Autumn/Winter/Spring and occassionally in summer too; to be fair it'd probably fare better nearer the equator.

[senormechanico]

Originally Posted by Paul Elliott

Here's one:

Solar power: ingenious solutions for boaters - boats.com

I'm not trading in my diesel-auxiliary sailboat though...

That thing must have a full time crew just for keeping up with the bird crap.

[Paul Elliott]

Originally Posted by senormechanico

That thing must have a full time crew just for keeping up with the bird crap.

Speaking of "crap", it looks to me like that's what they said (as in "Oh, crap!!!"), when they discovered that just covering the original topsides with solar panels didn't give them nearly the output needed to let them store enough power for 24/7 operation. And so they had to add those solar wings, roughly doubling the collection area.

At least, that's how I imagine the design and testing process went...