Previous in Forum: Frugal Engineering   Next in Forum: Power Question
Close
Close
Close
16 comments
Guru
Canada - Member - Specialized in power electronics

Join Date: Feb 2008
Location: Montreal, Canada.
Posts: 1357
Good Answers: 80

Ocean Energy Recovery

11/03/2012 2:09 PM

Our friend bett4haze gave us a link to some interesting info on Ocean Temperature Energy Conversion. This made my mind boil with the following ideas. Please feel free to add your insight to help potential promoters of this technology or other forms of it come up with a working commercial solution.

More on OTEC here

We could probably combine OTEC with solar and wave movement to increase the gain of energy at lower cost than independent technologies.
Symbiosis in technologies is an major principle we can use to succeed in competing with oil with the "clean" energy sources. Nature has used this philosophy for billions of years. It seems to work...

In the above example, one could combine the OTEC plant with large black floaters that wold use the waves actions to pump the surface water to the OTEC plant.

The surface water could get heated by a few degrees of when circulating in the above mentioned floaters.

This would cut on the pumping energy and increase the production. Even if not all the surface water is pumped that way,
pumping water is a better use of the wave energy than trying to make electricity out of it.

Similarly, the solar gain can be achieve at minimal cost because very little supplementary material is needed to take advantage of it.

The floaters to capture the waves could even be used to hold seaweed or oysters farms with minimal reduction of efficiency, take advantage of the floating infrastructure.

Similarly, the people caring for the farm would also maintain the floating system at little extra cost.

Another source of warm water could be the waste water from the cities. Could we get anything out of it?

Operating costs is often what kills the competitiveness of the new technologies. We need to find ways to get win-win situations.

Another interesting concept is the city of Toronto, Ontario, Canada that uses the cold water from the lake to reduce its air-conditioning bill. Could we combine this with OTEC to get some electricity out of this large, localized heat source that already has all the pipes installed?

What do you think?

__________________
Experienced is earned, common sense is taught, both are rare essentials of life.
Register to Reply
Pathfinder Tags: Ocean energy recovery
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Guru
Hobbies - Fishing - New Member

Join Date: Jun 2008
Location: Raleigh, NC USA
Posts: 13529
Good Answers: 467
#1

Re: Ocean Energy Recovery

11/03/2012 2:43 PM

Add this to your hat. All it requires is a 100° temperature differential. I'm with you. Why aren't we hearing more about these things?

http://www.popularmechanics.com/science/environment/4245896

__________________
Those who would give up essential Liberty, to purchase a little temporary Safety, deserve neither Liberty nor Safety. Ben Franklin
Register to Reply Score 1 for Good Answer
Guru
Canada - Member - Specialized in power electronics

Join Date: Feb 2008
Location: Montreal, Canada.
Posts: 1357
Good Answers: 80
#5
In reply to #1

Re: Ocean Energy Recovery

11/03/2012 6:42 PM

GA!

Exactly what you need when your region is blessed with high temperature geothermal source, it seems the way to go.

But what about the rest of the world?

__________________
Experienced is earned, common sense is taught, both are rare essentials of life.
Register to Reply
Guru

Join Date: Jun 2009
Location: South of Minot North Dakota
Posts: 8378
Good Answers: 774
#2

Re: Ocean Energy Recovery

11/03/2012 4:02 PM

"Operating costs is often what kills the competitiveness of the new technologies. We need to find ways to get win-win situations."

Well that pretty much sums up the whole reason why we are using what we use for energy sources. They are the ones that have proven themselves to have been worth the time effort and money that was needed to develop them into the highly effective and competitive sources we are using today.

The real issue with new tech is that too many dreamers believe that all we need is to have someone else do the work financing and developing of their ideas to make them work in the competitive manor they envision them to be.

Sorry but I have my own dreams and goals to finance and develop so I just don't have the time money or want to pursue others ideas for them.

Register to Reply Score 1 for Good Answer
Guru
Canada - Member - Specialized in power electronics

Join Date: Feb 2008
Location: Montreal, Canada.
Posts: 1357
Good Answers: 80
#6
In reply to #2

Re: Ocean Energy Recovery

11/03/2012 7:02 PM

Fair enough. I don't want to pay for somebody's windmill that cost more than it produces either.

I am just trying to find ways to make the interesting technologies pay for themselves.

I read a report that claimed that before the 70's, it took one barrel of oil to get 30 barrel of oil out and refined. They pretend that it is now closer to 3:1 because it doesn't gush out of the ground anymore. This means that if the trend continues, in 20 years, we will still have oil, but it might not be worth extracting at the present price. This will be a big tax on the growth of the society. Adding plain wind mills and solar energy production makes this ratio go down even more.

While I don't agree to spending billions on technologies that don't perform just to meet a political agenda, I believe that we must consider "competitive" ways to produce the energy we need.

Also we must find ways to reduce our consumption. This is another very important issue.

__________________
Experienced is earned, common sense is taught, both are rare essentials of life.
Register to Reply
Guru

Join Date: Jun 2009
Location: South of Minot North Dakota
Posts: 8378
Good Answers: 774
#11
In reply to #6

Re: Ocean Energy Recovery

11/03/2012 9:01 PM

Well where I live the oil gushes literally, 2000 - 3000 PSI surface pressures at wells are surprisingly common here, and the ones that are not self flowing still tend to be able to run at 1000 - 2500 Bbl's a day providing the crude can actually be transported away that fast which it presently can't.

Then there is the wind power issue we have here in our state where wind power has in fact continually proven itself to be cost effective to work with. We may not represent the rest of the world but at least we do represent something gainful!

But then again if someone wants to give us subsidies to produce oil and wind power on top of our present profits we are not dumb enough to say no to that either. Maybe that's how the 630,000 odd folks in this state manged to pack around $1.5 billion dollars away into our states saving accounts while the rest of the country spent itself broke and then some.

But what do we know about money and resource management for profit anyway. We are all just a bunch of hillbillys, dumb farmers, and uneducated prairie hicks that just don't get it you know.

Register to Reply
Guru
United States - Member - New Member Engineering Fields - Control Engineering - New Member

Join Date: Mar 2006
Location: Washington USA
Posts: 566
Good Answers: 53
#3

Re: Ocean Energy Recovery

11/03/2012 4:04 PM

Not enough bang for the buck.

Register to Reply
Guru
Technical Fields - Technical Writing - New Member Engineering Fields - Piping Design Engineering - New Member

Join Date: May 2009
Location: Richland, WA, USA
Posts: 20964
Good Answers: 780
#4

Re: Ocean Energy Recovery

11/03/2012 4:47 PM

ΔT is too low for good Carnot efficiency; hence such schemes require HUGE capital expense.

__________________
In vino veritas; in cervisia carmen; in aqua E. coli.
Register to Reply Score 1 for Good Answer
Guru
Canada - Member - Specialized in power electronics

Join Date: Feb 2008
Location: Montreal, Canada.
Posts: 1357
Good Answers: 80
#7
In reply to #4

Re: Ocean Energy Recovery

11/03/2012 7:04 PM

Is it worst than wind or solar?

__________________
Experienced is earned, common sense is taught, both are rare essentials of life.
Register to Reply
Guru
Technical Fields - Technical Writing - New Member Engineering Fields - Piping Design Engineering - New Member

Join Date: May 2009
Location: Richland, WA, USA
Posts: 20964
Good Answers: 780
#8
In reply to #7

Re: Ocean Energy Recovery

11/03/2012 7:31 PM

Probably. Also, it is typically remote from where the energy is needed.

__________________
In vino veritas; in cervisia carmen; in aqua E. coli.
Register to Reply
Guru
Canada - Member - Specialized in power electronics

Join Date: Feb 2008
Location: Montreal, Canada.
Posts: 1357
Good Answers: 80
#9
In reply to #8

Re: Ocean Energy Recovery

11/03/2012 7:47 PM

Why remote? There aren't any large city by the warm oceans?

__________________
Experienced is earned, common sense is taught, both are rare essentials of life.
Register to Reply
Guru
Technical Fields - Technical Writing - New Member Engineering Fields - Piping Design Engineering - New Member

Join Date: May 2009
Location: Richland, WA, USA
Posts: 20964
Good Answers: 780
#10
In reply to #9

Re: Ocean Energy Recovery

11/03/2012 8:00 PM

Not very near any major ocean depths....

__________________
In vino veritas; in cervisia carmen; in aqua E. coli.
Register to Reply
Guru

Join Date: Jun 2008
Posts: 859
Good Answers: 33
#12

Re: Ocean Energy Recovery

11/04/2012 1:30 PM

OTEC--Been done for years off the west coast of the Big Island of Hawaii. Drove past it all the time--It was called OTEC also--Google or Wiki it to get more data. They also were using GeoThermal from the numerous volcanic hotspots on the same Island. THe biggest problem in that technology was the corrosion factors of the sulfuric acid and other gases, and the inaccessability of the pipes at depth. I am sure all of this info is easily available on line, and from contributing members.

Register to Reply
3
Guru
Panama - Member - New Member Hobbies - CNC - New Member Engineering Fields - Marine Engineering - New Member Engineering Fields - Retired Engineers / Mentors - New Member

Join Date: Dec 2006
Location: Panama
Posts: 4274
Good Answers: 213
#13

Re: Ocean Energy Recovery

11/05/2012 10:02 PM

Back in the early 1980's, while working for Southwest Research Institute in San Antonio, Texas, i was involved in a major design project sponsored by some very prominent economic players in an attempt to come up with a viable commercial version of the sort of project off the big island of Hawaii (and a couple of other sites in the deep pacific). Bottom line- not financially feasible, for many of the problems mentioned already (material properties in harsh marine environments, extreme depth differential to achieve the required thermal differential, lack of viable sites near potential markets, etc.).

The US avy continues a low-profile OTEC development project (I believe associated with Lockheed, but I am not sure). Their primary interest is emergency supplies, not grid supply, I would suspect.

Like so many of these sorts of "dream solutions", the promises are based mostly on dreams, not science...When the science is done, they tend to lose their luster...

Register to Reply Good Answer (Score 3)
Participant

Join Date: Nov 2012
Posts: 2
#14

Re: Ocean Energy Recovery

11/20/2012 12:36 PM

Energy. It is all around us. We use the natural power of the sun for solar energy. Windmills likewise use the natural forces of wind to create power. The world has used moving water to create energy for centuries. I don't understand why we cannot use the most abundant and powerful force on earth: harnessing the natural incredibly powerful ocean tides and even waves. There is more ocean than land! It seems to me that this would provide more than enough natural power to supply the world with clean, inexpensive energy. Basically it is simple biomimicry. Huge clean energy generators could be used that would not cause catastrophes like off-shore oil drilling. I would make it one of our top priorities! I'm tired of paying outrageous, non-negotiable electricity costs because of the monopolies and lack of competition.

Register to Reply Score 1 for Off Topic
Guru
Technical Fields - Technical Writing - New Member Engineering Fields - Piping Design Engineering - New Member

Join Date: May 2009
Location: Richland, WA, USA
Posts: 20964
Good Answers: 780
#15
In reply to #14

Re: Ocean Energy Recovery

11/20/2012 1:53 PM

It's NOT inexpensive, but we see that you don't know that.

__________________
In vino veritas; in cervisia carmen; in aqua E. coli.
Register to Reply
Guru
Panama - Member - New Member Hobbies - CNC - New Member Engineering Fields - Marine Engineering - New Member Engineering Fields - Retired Engineers / Mentors - New Member

Join Date: Dec 2006
Location: Panama
Posts: 4274
Good Answers: 213
#16
In reply to #14

Re: Ocean Energy Recovery

11/20/2012 8:07 PM

For a very good, unbiased review of the actual costs/impact of most of the so-called "alternative energies", including the various schemes for extracting usable energy from the oceans, I suggest you begin with David MacKay's "Sustainable Energy- Without the Hot Air".

Available for free download.

Register to Reply
Register to Reply 16 comments
Interested in this topic? By joining CR4 you can "subscribe" to
this discussion and receive notification when new comments are added.

Comments rated to be Good Answers:

These comments received enough positive ratings to make them "good answers".

Comments rated to be "almost" Good Answers:

Check out these comments that don't yet have enough votes to be "official" good answers and, if you agree with them, rate them!
Copy to Clipboard

Users who posted comments:

Ace Boeringa (1); C-Mac (1); cwarner7_11 (2); HsHrt101 (1); kramarat (1); marcot (4); tcmtech (2); Tornado (4)

Previous in Forum: Frugal Engineering   Next in Forum: Power Question

Advertisement