Half a croissant, on a plate, with a sign in front of it saying '50c'
h a l f b a k e r y
Loading tagline ....

idea: add, search, annotate, link, view, overview, recent, by name, random

meta: news, help, about, links, report a problem

account: browse anonymously, or get an account and write.

user:
pass:
register,


                               

Ocean-going hydrogen economy

Floating offshore wind turbines power a hydrogen economy
 
(+2, -2)
  [vote for,
against]

Floating offshore wind turbines could be a great way to tap into a lot of clean energy.

This idea is to use such turbines as fuel stations for a hydrogen economy: hydrogen powered ships could stop along the way to fill. Hydrogen tanker ships (H2 powered of course) could carry energy to shore. Hydrogen airships could once again carry freight (& fearless passengers) around the globe.

Could flotillas of turbines become floating cities? For those with offshore tastes..

Other commodities that could be produced: desalinated water, oxygen, salt,

Making it all storm-proof might be difficult.

The economics would vary greatly depending on scale. Proposed offshore turbines are many-MW beasts designed along the centralized power model, but smaller units could also be practical, if people actually lived at sea. Many cheap small turbines, with live-aboard windmill-keepers.

afinehowdoyoudo, May 25 2007

By-product oxygen By-product_20oxygen
When you electrolyse water to get hydrogen, you also get oxygen [Cosh i Pi, May 27 2007]

Ocean Colonization http://en.wikipedia.../Ocean_colonization
"To be more than a novel experiment the colony must be able to support itself financially" [afinehowdoyoudo, May 27 2007]

Already 1/2 baked! http://pesn.com/200...hore_Wind_Hydrogen/
[afinehowdoyoudo, May 27 2007]

crazy artificial islands http://webecoist.co...artificial-islands/
[afinehowdoyoudo, Sep 11 2009]

possibly redundant with.. Oceanic_20wind_20turbines
[afinehowdoyoudo, Jan 03 2010]

[link]






       See author "Savage" Title "The Millenium Project" Chapter 1.
Galbinus_Caeli, May 25 2007
  

       I can't believe airships full of hydrogen would be an economic method of shipping energy. Liquid hydrogen in tanker ships, perhaps, although the energy cost of liquifying hydrogen is high.   

       But see link for one possibility of what to do with the by-product oxygen if this is done. The cost of liquifying oxygen is much lower than the cost of liquifying hydrogen (it doesn't have to be anything like so cold), as is the cost of a suitable tanker to carry it.   

       DON'T attempt to carry both on the same vessel, and DO keep them well out of each other's way!!!
Cosh i Pi, May 25 2007
  

       You would want to anchor a hydrogen extraction facility, but keep it mobile for relocation to climatically favorable areas to follow wind patterns or avoid cyclones.   

       The cost of liquifying hydrogen is insignificant given a 'free' and for all practical purposes inexhaustable supply of fuel.   

       I'd prefer a system made up of hundreds of widely distributed and modestly scaled systems. This would avoid the kinds of problems and costs associates with large centralized systems such as transportation costs, vulnerability, etc.   

       If the water was taken from places like undersea volcanic plumes, commercial mineral extraction may be also possible.   

       Of course this will never happen, as the corporate / political status quo prefers extracting hydrogen from petroleum because of the extreme profitibility of the existing oil infrastructure.   

       [+]
nuclear hobo, May 27 2007
  

       [nuclear hobo] I nearly agree with your comment - except that the cost of energy in systems like this is not zero. The fuel cost is zero, but the capital and maintenance costs are non-zero.
Cosh i Pi, May 27 2007
  

       Maintenance costs are essentially insignificant since the fuel cost is zero. That's why I quoted 'free', to qualify it.   

       This brings up an interesting point, though. If hydrogen was used as fuel to extract hydrogen from water, would there be a net gain or loss?
nuclear hobo, May 27 2007
  

       [nuclearhobo] "Maintenance costs are essentially insignificant since the fuel cost is zero."   

       Eh? Repair costs aren't proportional to fuel costs. Wind turbines might not need much maintenance, but whatever maintenance is required will be expensive on installations far offshore. Electrolysis plant will need maintenance, as will the liquifying plant for the hydrogen, and the docking and loading facilities for the liquid hydrogen tankers.   

       "If hydrogen was used as fuel to extract hydrogen from water, would there be a net gain or loss?"   

       A net loss, obviously - quite a big net loss, in fact. The proposal is for the system to be powered by wind.
Cosh i Pi, May 27 2007
  

       Indirectly, wind is solar energy. Indirectly, solar energy is nuclear energy from the fusion of hydrogen into helium. So, [nuclear hobo], this IS using hydrogen as fuel to extract hydrogen from water, although maybe not the way you meant?
afinehowdoyoudo, May 27 2007
  

       //A net loss, obviously - quite a big net loss, in fact.//   

       I would think you'd need to determine the amount of energy in a given amount of hydrogen and the energy required to extract the same amount from water in order to determine this.
nuclear hobo, May 27 2007
  

       Yeah, but you'd think wrong.   

       Essentially, when you "use hydrogen" you're reacting hydrogen with oxygen to produce water, and taking a portion of the energy released to be used for useful work. This could be in the order of 90% of the energy, but is likely to be much less.   

       So If I start with 1kg of hydrogen. Any my fuel cell is 90% efficient, and my electrolysis cell is 90% efficient, I can use 1kg of hydrogen to extract 0.81 kilograms of hydrogen from water. Less if I have to compress, cryogenically refrigerate, transport and distribute the hydrogen. why not keep the hydrogen I started with? This is like a screwy money/hydrogen laundering scheme, except there is no internal hydrogen service to be hiding from. Maybe your investment portfolio would benefit from some negative gearing? In that case I recommend you use this scheme.   

       In summary, in your own words the "amount of energy in a given amount of hydrogen" is EXACTLY equal to the "energy required to extract the same amount from water", at 100% efficiency.   

       Unless you're talking hydrogen fusion, in which case energy out from fusion is orders of magnitude higher than energy to extract from sea water and produce H2 & H3.
Custardguts, May 28 2007
  

       Oh, you can get hydrogen from methane and other hydrocarbons for less energy than from water. - at the expense of producing CO2.   

       And lastly, that quip about maintenance costs being essentially insignificant. -Have you ever worked in industry, built up a maintenance budget? I'm doing one right now, and I can guarantee that for any machine maintenance costs are anything but zero.   

       Feel free to cite examples where I'm wrong here, but you won't find any.
Custardguts, May 28 2007
  
      
[annotate]
  


 

back: main index

business  computer  culture  fashion  food  halfbakery  home  other  product  public  science  sport  vehicle