DM8954 | Yes, there would be some added cost, of course, but compared to the overall cost of the entire structure it might be minimal. The post and buoy system itself would be relatively cheap, essentially costing whatever the materials cost. Steel pipe of sufficient size might already be nearly strong enough. As progress is made on the Waterwalker, we’ll get a better idea of what this might cost at full scale, since it’s part of Vincecate’s design already. The price increase will come from shock absorbers and control systems . The current design doesn’t call for any control system, as it relies on flexible resistance (if that’s a real term) and wave averaging (also made-up). [hopefully you catch my meaning despite the invented terms.] Some waves will be up, others will be down, if you get a slow/delayed response from each rise and fall in various parts of the structure, it should even out and result in less motion overall. Now, control systems could be as simple as determining which edge of the platform is tilting upward more and decrease resistance on the high side and increase resistance on the opposite side so that it levels out. Simple balance sensors (a metal ball bearing in a curved tube and some wires) would probably suffice. A more complex system might map the ocean surface in 3D using a barcode-reader-style laser system and try to predict the effect of incoming waves on the system. If that EVER happens, it’ll be quite a ways out. This originally developed as just the sort of simpler design you’re talking about. Traditional designs call for thicker vertical legs to keep the vessel at the right height/depth. I intentionally tried to minimize the interaction between the surface waves and the vertical structure so the waves toss you around less in the first place. The primary buoyancy lies at a depth that will normally be calm because it is below the level of wave action, everything in between tries to let the waves go by with minimal resistance, and the living space remains well above the crest of most waves. It’s been pointed out that without this displacement in the water plane, it would be difficult to control/predict how high in the water the structure would sit. The sealegs will do 2 things: 1 – help resist whatever motion is still carried to the structure by waves & 2 – to suppliment the buoyancy. If we keep the deep buoys extremely close to neutral buoyancy overall, then the remaining weight difference would be held up by the sealegs. They’ve already been suggested for supporting an entire structure, so in this way they both stabilize and increase the safety factor of spare buoyancy. In this way you can control your depth in the water and have better performance if anything happens to a buoy or two (either deep or at the surface). If you want to enter a port and you’re riding too low in the water, perhaps additional flotation devices attached to the lower section of the legs could be inflated. Since the entire craft is buoyancy neutral, it wouldn’t take much to raise the deep buoys up towards the surface with just a little extra lift. This is inadvisable in the open ocean because the center of gravity would be too far out of the water, but in calm weather or in emergencies, this additional instability could be risked in order to dock at port. Some of the sealegs could be moved down to be attached directly to the legs in a rigid manner to fulfill the requirement of a design being ‘port ready’ within a few hours. Then the ‘port ready’ configuration could still be stable and balanced at the temporary cost of discomfort. I think the comfort and stability of this design over the simpler configurations would be worth the extra money. (assuming the extra cost is less than about 10-15% of the overall price) If the shipping container half of the equation can be solved inexpensively, the cost savings of that alone could help pay for the added complexity. My cost estimates so far seem to imply that the structure (shipping containers, sealegs, monopoles, & even wind turbine system) would only add up to about $18-$29 per square foot (labor & material transport not included). The habitable space above could be built almost like a regular house rated for hurricane force winds. The construction methods and materials would generally be the same except for the use of steel construction… which is actually already gaining some prevalence in larger homes and in areas with higher strength requirements to resist earthquakes or hurricanes. A possible exception to that is with my above suggestion of making even the habitable space water tight (to the point of floating, not just drenching splashes). With normal construction ranging between $150-$350 per square foot, it’s no more a premium than buying a prime piece of property to build your dream home on. Just to show you how I’m figuring my cost estimates at this point: Air-tight shipping container with hull coating, internal reinforcement, and pressurization valve:
$3,500 x 12 = $42,000
or
$7,000 x 12 = $84,000 SeaLeg (part of a WaterWalker) with leg, buoy, hinge, and cable:
$650 x 18 = $11,700
or
$1,125x 18 = $20,250 Monopole supports:
$27,500 x 8
+$35,000 x 1 = $255,000
or
$17,000 x 9 = $153,000 Wind Turbine System @15kw:
$50,000 x 1 = $50,000 [before house = $256,700 - $409,050(18-$29/sq.ft.)] Housing @ $200/sq.ft. for 3 floors @4800sq.ft.ea.:
$200 x 14,400 = $2,880,000 $3,136,700 = $3.2mil total ($218/sq.ft.)
$3,289,050 = $3.3mil total ($228/sq.ft.) Housing @ $350/sq.ft. for 3 floors @4800sq.ft.ea.:
$350 x 14,400 = $5,040,000 $5,296,700 = $5.3mil total ($368/sq.ft.)
$5,449,050 = $5.5mil total ($378/sq.ft.) These figures are very rough estimates and I tend to lean toward overestimation because cost overruns are more likely and unknown costs tend to add up as the budget is refined. On top of these costs would be waste processing systems, backup generators, hydrogen/oxygen/nitrogen generators (for energy storage and/or scuba), furnishings, gardening seeds and tools, and various other heavy equipment and storage containers I haven’t considered yet. Whew. …and on top of all that, I’ve even considered another modification to the design. I’m not sure whether it’s an improvement or not, but it has it’s advantages and disadvantages. This post is already too long, so I’ll go draw it up and play with it a bit before I update. |
DM8954 | After over a month of design changes, I have managed to finish updating my design. I have compiled it all into a seasteading wiki article. Link: Shipping_Container_Semi-Submersible_Waterwalker_Hybrid_Design (new name suggestions appreciated.) For those of you who are already familiar with this design or don’t like reading (It’s very wordy at the moment), scroll down to or click the link for “Version 3 Design“. Essentially, I replaced the ‘sealegs’ with pairs of surface buoys attached to cables connected to the deep buoy so that it pulls the structure up rather than sitting on the legs. This allows for greater height adjustment. The pairs of buoys are also allowed to move freely along a system of pulleys so that as waves move them up and down, they are allowed to move in relation to one another while still providing lift to the structure, so that wave motion does not transfer to the system as easily. I also added extension arms to hold more of these surface buoys further from the center of the structure, which increases the size of the base, making it more stable. Finally, I added a ferrocement shell to the shipping containers, which adds strength and ballast weight. This addition might even nullify the pressurization issue we discussed early on and increase the durability and length of the maintainance cycle for added life-cycle cost benefits. Please let me know what you think so I can continue to improve the design. I already have some ideas for another version of the design but constructive criticism would help me to refine it even further. |
Thorizan | In the news today: http://www.cnn.com/2009/TECH/06/12/recycled.homes/index.html http://www.sgblocks.com/ I really like the idea of structures like this attached to (and relatively easily detached from) the top of a modular spar, or other floating device. That way you can change the layout of your home — due to more money, new wife, less money, etc., without having to also exchange the seasteading structure as a whole. This should make financing significantly easier as well. Once you own your floating canvas, you’ll be able to decorate it as you see fit… live there for as long as you wish, and then sell the dwelling, purchase one that is more fitting, and move on to a seastead that is more to your liking with your new pad and lifestyle. Dynamic geography and dynamic housing to boot. Seems like a win, win. __________________________________________________
There is no fate but what we make for ourselves. Each to his fate. |
DM8954 | Does that look like home to anyone else? haha.  I haven’t touched my design in quite a while. I had some responses to some of the issues brought up in a diferent thread about the design but I’ve just been busy with other things. There doesn’t seem to be much interest in the idea anyways. If I ever get unlimited free time, I’m sure I’d get around to building a model… but that’s near the bottom of my list of things to do right now, unfortunately. Good links. Even if shipping containers are never used for buoyancy, at least they still have potential above the surface. |
wohl1917 | Using a 40′X8′X9′ so called ‘High Cube’ container, it would be tight but doable! The High Cube containers give you a 9′ ceiling allowing you to put in a drop ceiling to run your electrical, water and air conditioning and a step up into the bathroom to run your plumbing. Situating that sharing a wall with the kitchen makes for a small, but efficient living space for two/three people. Adding on is a matter of getting another container… |
bardamu | When I was working on my prefab home venture, these guys priced the custom buildout of two 40 x 9 containers with bedrooms, a kitchen, and living space. There qoute was around $70,000. That’s $97 psf. ($70,000 / (2 x 40 x 9)). This includes mechanical and electrical http://www.containerhouse.com/index.htm As the website shows, most of their work is for offshore oil and gas facilities. And, they were very open and enthusiastic about my quirky project. Good folks. Hope this is useful. |
billswift | There is another problem with using containers for flotation that wasn’t addressed – the corrugated sides have long complicated welds along each edge – a major corrosion risk. Anything that is going to be in contact with seawater, but especially any metals, must be as smooth and jointless as possible; every joint or angle is an invitation to corrosion. |
ellmer | I would go back to the basics. The benefit of a container is that it is a cheap mass produced enclosure (for transport) – and this is its limitation it is made for a different purpose. For our purpose a enclosure should last for ever in seawater with no maintenance need – only concrete can do this. Concrete shells have a 200 years proved service life in marine ambients floating and submerged in many industrial applications. I have built concete shells that enclose up to 200cubic meter of airspace at a cost of 331 euro per cubic meter and tested them for decades. We can form spheres, lens shapes, blimp shapes, not only container size but at the size of a family home – and we have operated such shells completly submerged, sub surface floating, surface floating. A surface floating concrete shell could look like this: it would need a breakwater (natural or floating). 
a sub surface shell would look like this: 
It could operate as allone in open water with no breakwater or be part of a “perl chain” floating breakwater itself . A autonomous submarine mobile habitat shell would look like this: 
It operates like a yacht but creates “leave coffee cup on table” in open ocean. – technically a private submarine with the size of a 68 squaremeter apartment. All those concepts have in common that they are concrete shell containers of considerable size – can be mass produced, can be individualized, and can create ocean capeable living space at average US and European housing prices. What i like most in CONTAINERS is “mass production of useable space in units”. We should define and mass build our own UNITS. Container yes, but built for our specific needs. Cheers, Wil concretesubmarine.com |
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