Yes. It will be slightly more efficient than conventional means,
since it could be isothermal compression. Unfortunately then you
also have the friction losses of moving a compressible container
to depth, and figuring out how to retain its shape upon allowing
it to surface.
Stick with methane clathrates.
David A. Smith
Possible, yes. Cost effective no. At 1000 meters you only get about
1400 psi. Hydrogen storage is much more, (depending on the system).
Let's say you have a compressing system, this system has a canister
full of Hydrogen, to be compressed, it's 1 cubic meter (Hydrogen
volume), and weighs 100 kilograms. You have a counter weight also 100
kilograms, and the same density as your compressor, but
incompressible. There is a pulley at the surface, and one on the
bottom of the ocean. To compress Hydrogen, fill, lower, and return to
the surface. Sounds like you need a very small motor to overcome
As you lower the compressor, Hydrogen is compressed, the volume of the
device gets smaller, less bouyant. At 1000 meters, that 1 cubic meter
is now .01 cubic meter. When you try to lift the compressor, it is
like lifting .99 cubic meters of water, because of the decreased
bouyancy. (.99 cubic meters of water x 1000 meters = a lot of power.)
The reason why I ask is certain places where ocean depths are this
great, there is also large wave action. Should an efficient method be
found to cature the energy of waves and store it as hydrogen or
another form, then these cannisters could be used to fuel ocean going
vessels instead of fossil fuels such as diesal oil. With 30 000
vessels on the ocean in any one given day, the reducton in carbon
would be significant and if it could compete with oil based fuels in
dollar terms then it may prove to be an alternative to present day
propulsion. Trying to supply electricity to a shore based consumer
market is very difficult with the distances involved and technology
needed to satisfy the consumer demands put upon the grid but supplying
cargo vessels with an alternate fuel may prove to be easier and in the
long term, a provide a greater reduction in Carbon. The idea if
implimented could make Hydrogen availible on demand and with advanced
orders to the marine industry world wide.
I need to clarify some points. The WEC would generate electricity
from surface ocean waves and there would have to be electrolysys at
the bottom where pressure is high. An umbilical cord from surface WEC
farm to the bottom would connect the two seperate but dependant parts
of the operation. The pressure already availible from the water colum
could be utilized to store the hydrogen and retrieving the cylinders
to the surface would also have to be considered. Here is a useful
site which is a good indicator of where the major wave action is
OK so far. Electrolysis of seawater generates hypochlorite ion,
bromate ion, hydroxyl radicals, and free chlorine. The hypochlorate
ion and free chlorine are toxic to aquatic life, but are also salable
chemicals (used in municipal water treatrment). The hydroxyl radical
will raise the pH to toxic levels. You will need to have a forced
positive flow from the site of electrolysis, prevent life forms from
entering, and bring these chemicals to the surface for collection
and / or neutralization.
A dumb waiter system would work for the containers, since they weigh
about the same once they are water-filled.
You'd be money ahead to simply store the wave energy as compressed
air, stored under a submerged "cup", and released during periods of
low wave activity through a turbine or air motor. Or store the energy
into heating salts...
David A. Smith
Osmosis could be used to filter out pure water elimanating the
problems with impurities.. At these pressures, it should work well.
Electrolisys would produce the Hydrogen and the Oxegen could then be
expelled into the surrounding water. From the studies I have read,
linear generators are proving to be the most efficient method of
capturing energy from waves and converting it directly into
electricity. The problem is uncertainty for marketing and that is the
reason for the hydrogen production. Also where the maximum wave
activity occurs, it is far from coasts but some areas are in the busy
shipping lanes where ocean going vessels could use these strategic
areas as refueling stations.
I know it is a far fetched idea but right now I am think of a
prototype to capture energy from ocean waves but with grid connections
and the distances involved, selling the electricity will be
difficult. With the price of oil sky rocketing, shipping companies
are looking under every rock for savings and alternative fuels. Ocean
going vessels are also one of the largest producers of carbon
emmisions and with carbon emmisions there aren't any winners. Some of
them could be convinced to try this method providing it is economical
and reliable. I'll keep post up to date if any developments come about
No, fouling is a serious problem. You don't really need much
more that a screen with wiper at the suction (deep) end.
You don't get oxygen when you electrolyze seawater, as I said.
Ionic chlorine is too readily available, so you get the species I
mentioned. The oxygen stays bonded to the other hydrogen.
You just killed all the aquatic life.
David A. Smith
Ok there will be problems with this system. May not be possible to
produce hydrogen with such a system. I was thinking of producing
Hydrogen from pure water which would be produced from a reverse
osmosis system but that in itself isn't availible as such and
producing it may cause problems and use to much energy.
Maybe difficult to store the energy in useful form. Il have to look
at other methods but ty anyway. All a process of design. Explore all
problems and options. storing the energy in a usefull and readyly
availible form could prove difficult but I do have a small shipping
company who is interested in the idea and now if I can get it to
With a reverse osmosis system the pressure would be availible at these
depths for the intake but it would have to be lowered at the outlet-
the energy would have to applied in the reverse side. Reverse osmosis
could supply more than enough filtered pure water for electrolysis of
water and maybe it would be a better system to store both the Hydrogen
and Oxegen for use in fuel cells when needed for propulsion? The
pressure for compressing the gasses would be from the water colum. As
for fowling, there isn't any algea at these depths but there is some
coral and other forms. Getting the cylinders to the surface could
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