This topic contains 28 replies, has 12 voices, and was last updated by Anonymous 6 years, 9 months ago.
May 30, 2008 at 11:00 pm #2753
What depths do you mean when you say continential shelf?
What depths do you mean when you say deep ocean?
I’m not an engineer, but I’d bet a case of Corona that a DP spar will not be able to stationkeep with onboard wind power. My sense is that the physics prevent it. It may be possible during opposing wind and current, but the power requirements for DP for that much windage in a 30 or 40 knot blow (not uncommon) and a few knots of wind driven or other current will be huge. DP has to be sized for maximum conditions. The spar will have too deep a draft to seek shelter. In light of the new methods of mooring (suction piles and suction embedded anchors) you might want to look at your cost figures again using up to date methodology. Certainly 10,000 to 20,000 ft depths are expensive,maybe prohibitively but 1000 to 3000 ft (OTEC depths) are not so much anymore.
I guess a pertinent question here is (if international waters are a requirement for the first offshore seastead) what are the range of depths of international waters. I don’t know. In some places it sounds like it could be 11,375′ which is certainly deep, probably too deep. If that’s the objective, something more ship shaped might be in order. What about seamounts and shallower noncontiguous depths? Are there substantial areas of those?
But if you are flying a flag of convienence, and providing an economic benefit (like renewable energy that also generates carbon trade credits or OOA protein, or jobs) there are probably dozens of small island nations and islands that would offer red carpets for the seastead in their waters. If the situation becomes untenable, pick up your moorings and go elsewhere. Suction piles are real cheap (just pipe with a padeye) and can be cut and abandoned with a small shape charge that rides the chain or wire down and detonates at the bottom. Really a one hour $500 job and off you go.
On another note, I’d like to suggest a “businesses” or business focused forum. Revenue will be a primary concern won’t it? I would think it needs to be a part of the strategic planning and design work.May 31, 2008 at 9:04 am #2765
For something as deep as a spar, water current wins every time. The total area presented to the current is many times the area presented to wind, even with the most efficient wind turbine and sail arrangement I can think of. Water also has more mass than air by a considerable amount. I just don’t see any way that wind power alone achieves station-keeping for a mass of hundreds, to thousands of tons. The only reason sailing shipscan use wind to go against current is their hydrodynamic shape and relatively low drag, smaller ‘wetted’ surface (draft).
May 31, 2008 at 9:36 am #2772May 31, 2008 at 10:18 am #2777
- I’m afraid there is only one means of station-keeping without importing fuel, and that is mooring.
- Powered station keeping is just too wasteful.
- even if you had energy to burn, it requires one of two things: constant vigilance to adjust the power applied, or more expensive electronics to automate the task of applying power and steeering, and even then it still requires watchstanders.
“The only reason sailing shipscan use wind to go against current is their hydrodynamic shape and relatively low drag, smaller ‘wetted’ surface (draft)”
May 31, 2008 at 10:53 am #2780
- …and that the wind blows orders of magnitude faster 😉
From what i understand, claims made on the EEZ are intended for, and understood as only applying to natural resources.
I think, if we keep our hands off any natural resources, we could typically reside in waters claimed as an EEZ. I dont think nations would be particularly eager to defy our independence if we do reside there. There wouldnt be much to gain, and they would have to get away with setting that precedent in front of the entire international community, which i figure wouldnt be too enthausiastic about such a unilateral expansion of the scope of existing treaties.May 31, 2008 at 3:40 pm #2791
“…and that the wind blows orders of magnitude faster ;)”
May 31, 2008 at 3:55 pm #2792
- Is subsistence fishing exploiting a resource? Commercial mariculture?
- Is a windmill exploiting a natural resource?
- Is seawater desalination for drinking water exploiting a resource?
- Is sunlight a natural resource?
- Radio frequency spectrum?
- Convenient mooring spots- that’s surely a limited natural resource, no?
It’s all in how you define it and what you can make stick.
August 3, 2008 at 3:21 pm #3538
- There are also advantages to being an American citizen, and isn’t an individual State’s boundary limited to 3 miles, the federal law’s boundaries end at the 12-mile limit? Outside a state’s jurisdiction, you are only subject to federal regulation. Outside the 12-mile limit, you’re only subject to Maritime law, which in US “territorial” waters like the EEZ, means treaties the US has signed. I’m not prohibited from posessing a brand-new, fully automatic AK-47 as an American citizen, I’m merely prohibited from importing it into the United States (except for military and LE aganecies).
- Perhaps you don’t have to fly the flag of another nation, you just comply with federal law and ignore state laws. find technicalities which allow you to do pretty much what you want and lobby to change whatever doesn’t work for you. It’s still an incremental improvement.
- There’s no federal law against most of the things people want. It’s mostly your neighbors who are trying to run your lives, and the federal government is just a symptom of that. Doctors are licensed by states, prostitution is not a federal crime. Unfortunately, most recreational drug use is, as are a lot of weapons.
-good artice on the subject item. Presumably, the economics of offshore wind energy for offshore communities would be even more favorable.August 4, 2008 at 9:26 pm #3541
In one of the links on here, I came across the idea to use the electricity generated by windmills to separate hydrogen from oxygen in the seawater. I’m sure that there are energy losses due to this, but the question of transportability and energy storage might make this viable. I’m sure we could come up w/ a viable business model to make the byproducts (oxygen, salt, minerals, etc.) provide a revenue stream as well.
Thoughts?August 4, 2008 at 10:11 pm #3542
I remember Kucinich talking about windships during the 2004 presidential run. He wasn’t getting much press on the subject, but I thought it rather interesting. Harnessing the excess wind when it was not needed, and utilizing it when it is calm would be nice. I know of a product called Essence of Life: Liquid Mineral Complex that is supposedly minerals from the ocean, so something like that already is done, and it wouldn’t be difficult to break in on that racket. Revenue streams from the sea are not difficult to achieve… having healthy margins to start out with will be the hardest to do.August 4, 2008 at 10:17 pm #3543
Offshore wind turbine with multiple wind rotors and floating system
Looks like someone already beat us to it.August 5, 2008 at 10:48 am #3544
The energy efficiency of water electrolysis varies widely with the numbers cited below on the optimistic side. Some report 50–80%August 6, 2008 at 11:18 pm #3551
But it does make the wind-, solar-, nuclear-, or whatever-power portable by shoving it into a fuel cell. The question is whether we need portability more than efficiency. Boats and other forms of transportation will function better on portable fuel coupled with batteries than just with batteries alone. Some things to think about, maybe. Great link, thank you.August 16, 2008 at 11:19 am #3590
I would recommend vertical turbines as being an economical solution for seasteading.
My thoughts about windmaills are to maximise benefits while reducing materials used and energy expended. To this end, I would place an “archimedes screw” on the turbine axis to lift water into a storage cistern. During periods of low energy availabilty, it is simple to release some of the stored water to generate electricity (microhydro).
A Newscientist article [fighting fire with a steam machine – 06 March 2004] describes a fire fighting hose nozzle that doubles up as a “engine” (method of propulsion). It is powered by steam so that sunlight and seawater, two abundant resources for seasteaders, can provide a ‘free’ (neither economic nor environmental cost) technique to move around the oceans. The ‘motor’ has no moving parts and seems to be cast in one piece – minimal maintenance and easy replacement.
I have just read “Sea Energy Agriculture: Nature’s Ideal Trace Element Blend for Farm, Livestock, Humans” by Maynard Murray, MD . This book suggests that seawater (within some specific criteria) can be diluted to 9% with fresh water, NEVER distilled water, to provide the perfect hydroponics solution for superior agriculture results.
The forum ‘Infrastructure’ is closed to new topics and replies.
Posted on at