Affordable, long-term liveaboard?

Here is an interesting solar electric platform from the Swiss company MW-Line SA

http://www.mwline.ch/en/bat/aquaC60/C60std_tech.html

Any comments? I could see utilizing a platform like this with a streamlined enclosed cabin. Mine would have more panels, more batteries and larger electric drives. These things are in service on Lake Geneva.
Aquabus C60 Standard - technical features

Length 14,0 m Width
(or Freycinet gabarit) 6,6 m
5 m
Draft 1 m
Empty weight 10 t Fully loaded weight 14 t Electrical Engine EE2 2 x 8 kW Batteries tension 48 V Solar panel surface 20 m2 Cruise speed autonomy, without sun 8 hours Autonomy with solar, over 12 h Passenger capacity
(selon les pays) 60
(75) Savings on exploiting costs compared to a thermic engine 45 times less costly

 

Why I think all professional solar boat designers are using catamarans:
First, you must have sufficient beam to support a large area roof for holding lots of photovoltaic panels.

Second, Malcolm Tennant says it much better than me in this article about power cats.
http://www.powermultihulls.com/magazine/articles/displacement or plane.htm

​

In our Premier Issue, Malcolm Tennant, one of today’s foremost power catamaran designers, discusses the principles of planing vs. displacement catamarans. In this article he makes clear his choice of the displacement cat.
For some fifteen years now our office has been designing powerboats that combine something of the old and something of the very new. To make a leap forward in comfort and economy we looked back to the close of the 19th Century and the early years of the 20th. We have taken the powerboat wisdom of that time and used it in the designing of very modern power catamarans that can have much more living space than their monohull cousins, and that easily surpass them in comfort and economy. Current thinking has it that to go fast in smaller craft it is necessary to plane. This is because the usual monohull displacement craft are restricted to a speed of approximately 1.34 times the square root of their waterline length (Froudes Law). To drive a normal displacement vessel faster than this requires an inordinate amount of horsepower and may even lead to foundering in their own bow and stern waves, or by rolling the gunwales under from the enormous torque produced. Planing is a way to circumventing Froudes Law by getting the vessel to plane on top of the water where the wave making drag is no longer a restriction on their performance. However, planing craft do need to be relatively light, ie: have good power-to-weight ratios, and planing surface-area-to-weight ratios; are very inefficient when they are not planing, and are not as economical to run at some speeds as the displacement craft. So we seem to have two distinct type of boats: a. One that is fast, but uneconomical at slower speeds and can have a bone-jarring ride in a seaway; b. The other, that is economical and comfortable in a seaway, but is slow. Is it then even possible to get a craft that combines the best features of both these types? A boat that has reasonable * even good * performance with excellent accommodations and is still economical to build and run, and has good seakeeping capabilities: * or is this just one of those designers’ pipedreams?
One quite successful attempt to achieve this dream was made by Tom Fexas with his Midnight Lace series of monohull designs, in which he used long, light, semi-displacement hulls to improve economy without compromising performance too much. These boats were, in fact, a compromise (aren’t all boats?) and, to me, only partially successful by reason of his definition of a slim hull which was, of course, forced on him by the need for stability, accommodation and sea keeping. To Tom Flexas a slim hull was one that had a length-to-beam ratio of four (the waterline length was four times the waterline beam). This was certainly narrow by contemporary planing boat standards, but was unexceptional when compared with earlier boats, or with types of hulls that I am proposing should be used.
Before the improvement of the power-to-weight ratio of the internal combustion engine, and the development of the hard-chine, low-deadrise hull allowed boats to plane, there was only one way to go fast: building long-and-slim, and in the first decade of the 20th Century we find boats such as Slim Jim, that were achieving speeds of 15 knots from a 15 HP engine driving just such long hulls in 1905. Typical of the early boats was Defender: 16.2m (53') long, having a maximum hull beam of 2.28m (7'6"). Headroom under the flush deck was only 1.45m (4'9") and she slept six in berths only 500mm (18") wide. In anything of a seaway it would have been incredibly wet and uncomfortable. The boat had a great deal of grace and elegance to her lines, but her rolling at sea, and lack of accommodations, would be totally unacceptable today except for one small detail: a 48 HP motor propelled this 16.2m boat at 16.5 knots! Is it possible, then, to reconcile these old, easily driven, but incredibly uncomfortable hull forms with the current, ever increasing demands for more interior space and more home comforts that can be the downfall of many a well-designed planing craft? I believe the answer is: catamarans! By joining two of these long, slim hulls together and surmounting them with an extensive superstructure, we are able to provide even more than the currently desirable amount of accommodation and at the same time stabilize the hulls so that rolling is no longer a problem.
Even a very cursory look at sailing catamarans will show that they are not restricted by Froudes Law. Their very fine hulls place them on a very different part of Froudes’ wave making continuum, and results in their having a very much higher hull speed than he ever envisioned from his observations * in the order of 30+ knots is not unusual for these boats. Certainly the boats with this sort of performance are very lightly loaded racing craft, but even the more heavily laden cruising boats do not have much trouble breaking the 1.34 barrier. If these sorts of speeds can be achieved under sail, than it should be much easier under power. Towing tank tests of long, slim hulls with high prismatic coefficients (fine hulls with a fairly even spread of displacement from bow to stern), such as our displacement powerboats exhibit, have shown no catastrophic increase in wave drag at speed/length ratios above approximately 1.4 * such as occurs with "normal" displacement hulls. These high prismatic hulls have a higher displacement hull speed than is "normal." This test data is further supported by the precisely measured performance tests of such boats as the Zenith-47 Antaeus, the Awesome 2000, the Mako-61, the Jaybee and the Icarus 46 in the full-sized ocean test tank. All these boats have prismatic coefficients greater than 0.66 and all easily exceed their theoretical hull speeds, while returning exceptional fuel economy.

So it would seem, that all we have to do is to make power catamarans with long, slim hulls, and then we will have speed, economy and accommodation. The potential is there, but is it really that simple? The answer, of course, is "no" * not quite! If we compare a sailing catamaran with a keelboat, we will see that the catamaran has one immediately obvious advantage. It is lighter because it is able to eliminate the lead keel upon which the keelboat depends on for its stability. In the case of the powerboat, there is no such advantage. The catamaran may, in fact, be heavier than the monohull because of its increased area. All is not lost, however, because while the skin area is increasing by the square, the interior volume is increasing by the cube! This possible increase in weight may be a problem with planing catamarans because of their limited planing surface, but it does not mean that our dream is impossible. ​

The displacement catamaran is not as susceptible to overloading as is the planing craft. The hull speed of the displacement boat is largely dependent on the L:B ratio of the hulls and this does not change very much with modest overloading. This does, however, bring up one of the limitations of the displacement boat. To work successfully, the L:B ratio of the hulls should be in excess of 10, and preferably higher. Consequently, if high displacements and length restrictions force short, fat hulls on the designer, then the displacement approach will not be successful. In this situation the only recourse is to lengthen the hull until the requisite L:B ratio is obtained, or to use a planing hull form. It will be apparent from this, that the displacement concept would seem to have little place in boats shorter than 10m (32'), unless they can be built light * or a very modest performance is required. I have designed smaller displacement boats that achieve quite credible 15-knot cruising speeds from very small horsepower (43 HP per side) engines. But if performance on par with planing vessels is required, then the displacement boat must be able to have long, slim hulls, preferably without the planing boats’ low deadrise, submerged chine sections, as this increases the drag substantially, and even more if the chines break the surface. This, then, is the approach we have taken with a lot of our power catamaran designs: long, slim, easily driven round-bilge, minimum wetted surface hulls that give performance on a par with planing craft, but with considerably better sea-keeping capability and better fuel economy.
It is, of course, possible to question whether these boats really are displacement craft. Current theory says that for vessels of this length, to go this fast, they must be planing. In fact, if we accept the usual definition of planing vessel, namely: that it has a speed/length ratio of more than 2, then these boats are clearly planing. However, a boat is said to be planing when most of its mass is supported dynamically by the downward directed thrust of the water. A vessel that is planing will typically have a bow out trim and will have bodily risen out of the water. The waters are muddied a little by the fact that there is no sudden jump from displacement to planing. It is a continuum and somewhere in the speed/length ratio range from 1.5 to 2 the craft would be considered to be in a "semi-displacement" mode. We have now designed a large number of displacement power cats exemplifying the "long and slim" approach of powerboat design.
The Zenith-47 displaces 13 tonnes fully loaded, and motors at 20 knots maximum * much more economically at 16 knots * with only two 122 kw (160 HP) pushing hulls with a 24.5 knot hull speed. A monohulled displacement boat of this length would have a hull speed of about 8.5 knots. The smaller Nomad and Cortez powerboats also have a similar hull speed but are optimized for more for economy with slower speeds with small engines. The Icarus-46 has a top speed of 25 knots from two 150 kw (200 HP) turbo-charged diesels. At the upper end of the scale is the Mako-61, an 18.6m (61') game fishing boat with a hull speed of 37.5 knots which would yield an easy 30 knots with around 500 HP per side. In the interest of economy, this boat is intended to cruise at 16 knots * with a maximum of 20 knots * using twin 150 kw (200 HP) engines.
These performances are very much faster than those of the traditional displacement boats of comparable size and are on a par with that of a planing boat of similar displacement, but with lesser power requirement and subsequently greater economy. I believe the performance of these designs demonstrates the potential of the displacement power catamaran to be that very elusive and ephemeral animal; the best of all possible worlds: combining excellent accommodation, comfort, and economical performance with good old-fashioned seaworthiness. It seems to me that there is no reason why this old "long and slim" principle should not be applied to lightweight boats with less superstructure and even finer hulls, to produce 30 or even perhaps 40 knots of fuss-free performance from quite modest horsepower.
In fact, this belief has been partially tested with two offshore designs: the 17.5m (57') Red Diamond II, designed for a Japanese client, capable of a top speed of 33 knots (cruising at 24) from twin 320 kw (430 HP) Yanmar diesels; and the 20m (65') Awesome 2000, which has a top speed of 28 knots, and an open ocean cruising range of 3,000 miles at 15-knot speed. This craft has made the trip from Long Beach, California Hawaii using only her internal tanks. Although these displacement cats may not be the fastest things around in flat water, they have demonstrated an ability to maintain much higher average speeds than most other craft regardless of sea conditions. In situations where the high-speed planing monohull is forced to drastically reduce its speed, the displacement catamaran is able to continue on with very little reduction in performance.
This ability is displayed day in and day out by the rapidly expanding commercial catamaran ferry fleets whose operators recognized the economic advantages of this concept early on. It has often been pointed out that many people with displacement boats try to push them too fast and, consequently, would be better off with a planing boat. For these people there is now another alternative: displacement boats with the performance of planing craft and the frugal thirst and smooth comfort of the traditional displacement boat.

​

Copyright© Multihulls Magazine 2002 All Rights reserved.
Send comments to Multihulls Webmaster. ​

 

The example of the Swiss Aquabus... looks to have about an 8:1 ratio, 10:1 at most.

 

Lake Geneva to the Riviera?

Deering wrote:The example of the Swiss Aquabus... looks to have about an 8:1 ratio, 10:1 at most.

I am not sure about that since the waterline is actually concealed by a wide overhang at the rear. But with a heavy load I can imagine that the waterline beam gets effectively wider rapidly. The specs on the web site do not give the ratio. Also the hulls are 14 meters, a bit shorter than my concept. But if I had this platform, I could easily work with it to do what I want. Its big fat stern makes it more flexible for different loads. There are already a number of these boats operating around Europe. They are said to be capable of ocean criusing up to 36 km from shore, a big plus. I could summer in Lake Geneva and winter in the Mediterranean via the Rhone. Anybody know if the Rhone is navigable for a wide boat between Lake Geneva and the Riviera?

 

Jonathan,
Have you considered entry level aerospace technology to build your hull? im talking of prepreg, foam cored, with liberal use of carbon fiber reinforcement.

Vacuum bagged, high temperature cured (not autoclaved) with lots of honeycomb cored panels for interiors/furnitures?

Saves a lot of weight.

 

Actually have used these techniques in the construction of a solar car. I wonder about the construction costs, maintenance and durability of such hulls. However, it would no doubt make a lot of sense above decks. Have you built substantial boats using hulls with this technology. A number of others have recommended this too. I want to be able to mass produce these hulls. And I wonder if this is more of a custom boat process.

 

Yes i did on the interiors for boats but have built composite airframes on a production basis.

I have used foam cores for decks and used honeycomb for interior panels. Saved a lot of weight.

I used honeycomb only in interiors as it might trap water on the hull.

For prototyping I use flat honeycomb core panels glue them together and finish the edges with fairing compound. For curved panels, I slit (kerf) the inner skin, bend the panels, then add a couple of reinforcing layer on the hidden side.

I use wood veneer to finish surface or use a cored panel with the outer side shiny.

Since you are building a cat, I would reccommend using unidirectional fibers (carbon or fiberglass) on crossbeam caps. It increases strength tremendously while reducing weight.

 

Wow. When I started the thread, I was hoping for a little more diversity in the responses. I guess I'll post again, wording things differently.

 

Wow, it's people like this that gives bad name to environmentalist

"Show some respect to boating professionals then one may get better free advices" says Green Building professional with electronics and mechanical engineering background.

How did this project go? I guess no where?
Almost 9 years later we still can NOT do this due to technology shortfall in inefficient solar panels, heavy and low energy density of the cheap battery technology, insufficient electric propulsion technology for stated requirements, and a thread originators lack of understanding in laws of physics in multiple disciplines.

This is not a criticism, but a fact-check for many environmental caring people following political values instead of scientific facts.

 

Noah Wannabe indeed!! This project has gone quite far in that a solar powered catamaran has been built with this technology that has circumnavigated the world.
http://en.wikipedia.org/wiki/Tûranor_PlanetSolar

Although it has twice the length and beam of what I have envisioned, it has proven the technical viability of solar powered live-aboard catamarans. The cost of this boat was many millions of dollars, but then its goal was to be a blue water cruiser whose purpose was far more ambitious than mine and financed by an individual with very deep pockets whose goal was in part to have his name attached to a very ambitious "first" circumnavigation by a solar powered boat.

One of the reasons I have stopped using Boatdesign.net as a sounding board for this project is that there are too many know-it-alls who talk authoritatively of things that they know nothing about. Constructive criticism is great, but not statements that purport to be factual but are based on nothing more than the poster's ill-informed opinion.

 

Thank you for your response Jonathan.
My son's name is Jonathan too. He is stubborn but usually comes around to reality after about six month.

Let's compare your original assumptions and requirements to your project progress. “this” project in this forum refers to JonathanCole's project NOT any other project. Any other projects would be “those” projects.

Your project goal was:
- it costs less than a house (<$150k) >> Laughable budget. My 23' fishing boat cost more than that in 2005
- Very low maintenance costs
- 1000 square feet of living space >> 1000 square feet of living space on boat is worse than yachties looking for a condomaran. Definitely NOT a sustainability minded conservationist.
- Carries a mini car that can be off loaded on piers or shore >> Carries a mini car? A true Earth lovers should ride a bicycle. Many of my colleagues in Berkeley and Portland does that.
- carries a small inflatable tender
- super efficient
- 5-8 kts with short burst of 12 kts possible
- twin electric drive
- extremely maneuverable
- Can be piloted by a single operator
- Pollution free >> Pollution free? Including embodied pollution? Solar panel, lead acid battery, permanent magnet in electric motors and generators, that type of pollution?
- Very low fuel costs
- Hybrid energy sources (solar, wind, current, wave, biodiesel generator, direct from mains battery charging) >> Where do you get Bio-diesel? Whale blubbers and seals? Genetically modified corn oil?
- Quiet
- No fumes >> No fumes? Does this include composite and polymer outgassing? Your mini car would outgas quite profusely just parked on your project boat.
- Idiot-proof >> Idiot-proof? Every body is an idiot as soon as they get on a boat other than a working boat for a work. Ask any landlubbers
- Bullet-proof >> Bullet-proof? Now you talk like an union electrician talking about his perpetual conversion of electrical theory. Only drug cartels and navy should talk about a bullet proof boat.
- I plan to spend the $150 k to build this boat, it will be the first of its kind to make the water planet fully inhabitable with very low operational costs.
- HDPE for a hull material >> Seriously? Cheap kayak rotomold material? You need to consult a real engineer even if they are not a naval structural engineer. HDPE doesn't have right properties for hull material of this size boat. maybe HDPE as an exterior coating material.


Since I gather your project never got off the napkins, let's compare your initial requirements against “that” boat, Turanor Planet Solar.

it costs less than a house (<$150k)
No - Turanor Planet Solar (TPS) cost $19,000k. Your budget would not even have covered study plan cost. Near by my house, there are many houses that cost more than $19 millions. Google Earth Stanford University's surrounding neighborhoods, or Zillow.
Very low maintenance costs
No - My guess is annual storage cost for TPS is more than $150k even if it sits on drydock excluding insurance. Annual electronics, electrical, propulsion, bad Li-Ion battery cells, coolant, lubricant, corrosion related maintenance, etc will be quite expensive.
1000 square feet of living space
No - TPS doesn't have 1000 sf of LIVING space. My guesstimate is 700 sf. Maybe if you include surface of the solar panels on roof deck.
Carries a mini car that can be off loaded on piers or shore
Maybe - Possible on TPS, but even these guys knew one can't have a car aboard and call their boat a sustainable yacht.
carries a small inflatable tender
Yes - First legitimate goal met. RIB tender, better than a typical inflatable.
super efficient
Not really but - The most efficient commercial grade solar panel can only convert less than 16% of the sunlight striking solar panels. Considering inefficiencies in charging, voltage and current control losses, motor inefficiencies, mechanical transmission energy losses and various energy conversion inefficiencies, overall efficiencies from solar energy at solar panel to energy output would be less than 8%. But since it was super inefficient from "FREE" solar energy, we may agree to say it was efficient. Was it really free? Not if 93kW worth of solar panel costs more than a million dollars to install.
5-8 kts with short burst of 12 kts possible
Yes - TPS cruise 7.5 knot and tops out at 14 knots. Not bad for an electric boat. But US nuclear submarines with electric propulsion can do 25+ knots under water, so umm...
twin electric drive
Yes, not very reliable but they did have them. TPS electric propulsion broke down during their circumnavigation voyage.
extremely maneuverable
Maybe - TPS was probably maneuverable most of the time. Extremely? No way with solar panels extended and unladen weight of 90 tons. My sea kayak with a carbon fiber oar is extremely maneuverable. My 23' boat with twin outboards in harbor is maneuverable but I wouldn't call it extremely. TPS with twin stern props and bow thrusters would be maneuverable but not extremely. Without bow thrusters on cross current, it will be very UN-maneuverable.
Can be piloted by a single operator
Yes on TPS with literally tons of electronics at millions of dollars.
Pollution free
No – Solar panels and Lithium batteries alone are very toxic to mine and manufacture.
Very low fuel costs
Yes technically but NO practically as it's operational maintenance cost would be very expensive.
Hybrid energy sources (solar, wind, current, wave, biodiesel generator, direct from mains battery charging)
Yes – it is possible with many.
Quiet
Yes – relatively speaking. Twin 60kW electric motors are NOT quiet but much quieter than diesel equivalent. 60 kW is 80 hp. Typical motor on a shop drill press is less than 1 hp.
No fumes
Yes – it is low emission but NOT emission-free.
Idiot-proof
No – they definitely would not let you test drive it. Don't feel bad, they won't let me either.
Bullet-proof
No – Easily shattered and very fragile. Solar panels, lithium batteries, carbon fiber reinforced epoxy composite. The whole TPS is a delicate instrument.
I plan to spend the $150 k to build this boat, it will be the first of its kind to make the water planet fully inhabitable with very low operational costs.
Most definitely NO. Not at $150k, not at $1.5 million either, at least not the way you and unscientific, Liberal, Western environmentalist influenced concept of sustainability. Turanor Planet Solar is technically possible at $19 million. Even then nobody else wants it. There is not a single billionaire ordering a new TPS or anything similarly propulsioned while there is a yacht building race among billionaires for the biggest yacht. http://www.forbes.com/sites/timthomas/2012/03/25/the-top-yachts-spot/
TPS is a prototype test research yacht to see if there is a need for TPS and how technology can be improved. Currently it does not meet anyone's need, and certainly not for a middle income retirees from developed countries.

This is not a rocket science, many South Asians live aboard on Sampans and 'small' junks.
First circumnavigation by solar powered boat was Magellan. Wind is the converted solar power with planetary energy assist just like Photo-Voltaic panel is converted solar power. Magellan circumnavigated on pure, non fuming boat, solar power in 1519, 495 years ago. It wasn't spacious, it wasn't single handed and it did have high maintenance.

You can purchase a good used, offshore, cruising sail boat and possibly do what you want for $150k with minimal carbon foot print if you have a seamanship skills and sound engineering mind. You will need a gasoline 10 HP outboard for harbor maneuvers with good skills. Or you can convert a used trawlers with a diesel engine for that price. Used offshore, cruising sail boat with practical solar powered electrical propulsion may be barely possible for coastal use only, but you probably need more than $150k and maintenance is still somewhat expensive.

The collective minds in this forum is quite astoundingly wise and practical. I originally commented on this thread because you, JonathanCole, was very condescending and lacked basic laws of Physics and material science. Obviously you don't have any engineering background. I wanted to see how far your plan has progressed and let other “Green” boat builders/designers (newbies and environmentalist types) see the state of renewable propulsion technology factually.

There are many renewable boater forums with real scientific technologies. Check these links for electric boating. Where do you go for sounding off your ideas?
https://groups.yahoo.com/neo/groups/electricboats/info
http://endless-sphere.com/forums/viewtopic.php?f=39&t=9806&start=150

For me, I am still waiting for diesel-electric hybrid propulsion technology to mature for some type of fast semi displacement catamaran hull of 34-40' LWL. Then I will probably consult a professional boat designer for a motor sailer.

 

First,

does not apply. This thread was almost 100% hijacked from the thread originator.

Second, while

may be true, the possibility or 'viability' was never doubted. It's the practicality that was doubted, and still is.

 

SamSam and Filmdaddy, my bad. The thread originator was fine, I am sorry. It was a hijacker that lacked Physical laws.

Filmdaddy, how did your search go? if you are still around.
I am slowly getting my search started. If I can get stretched Vardo by Richard Woods with proven, reasonably priced diesel-electric hybrid propulsion then it will be within my ball park of ocean cruising, economical live aboard boat.
http://www.sailingcatamarans.com/index.php/designs/4-30-to-40ft-catamarans/225-vardo

 

He started another thread but hasn't posted since 2011.
http://www.boatdesign.net/forums/pr...e-long-term-liveaboard-design-query-9839.html

If you click on a poster's name, you can find all of their posts plus other stuff.

 

Thanks SamSam.