Good to see LM slowly making an effort to atone for decades of building war machines.
We are slowly moving from the age of technology to the age of Integrity, Wars will no longer be viable due to our close economic and social inter-dependency.
Smart players will see this and diversify core business.

I can't believe that boiling a fluid with a low point to drive a turbine and the re condensing it is more efficient than using a Stirling Cycle engine. Air temperature is often a little higher than the water temperature and the simplest, cheapest passive solar thermal collectors will add a significant amount of energy to the system. I don't thing that building and maintaining a deep water structure is really cheaper than building the additional miles of insulated pipe to bring the cold water to shore, even with the difficulty of winding it in through a breakwater. especially if you can add industrial waste heat to the equation.

Slowburn, my thoughts exactly. Coupling this to a high heat output industrial operation and pumping in the cold water would seem to make far more sense. The temperature differential would be far higher, allowing for far more power output.

A Calorie is 4.184 Joules. A Watt is one Joule per Second, and a Calorie is the amount of heat needed to raise one cc. of water one degree centigrade. A cubic Hectare, 100 meters cubed. is a million tonnes. and a tonne is a million grams. or ccs of pure water.
This gives the 'available' energy from a cubic hectare as, 4,184,000,000,000 Joules. per degree centigrade temperature change. This translates to 1.162 Gigawatt hours per cubic hectare per degree centigrade....of 'available energy'. Reality dictates that with low temperature difference the coefficient of performance is also very low. But this is less important with free energy! Volume is what counts!
Penn State University have done substantial research on Thermo-Acoustic effects, eg. Benn & Jerry Thermo-Acoustic Refrigeration, as well as the reverse effect. Ear-piercing noise! from a thermal source. Just a thought, OTEC Thermo-Acoustic Power hypothetically could be very simple to construct. Just a long tube and bucket-brigade honey-comb heat exchange baffle. Hmmm?

I have to believe that Lockheed martin has looked at alternatives and is going with the choice that makes the most sense, they have a team, many teams of people who have spent their entire lives to that point studying and practicing the field of science specific to this sort of thing, and they are the best out there because lockheed makes so much money.
I have to believe they know more then people on the internet, who may be smart and have common sense ideas but the idea that a better solution would be simple and off the top of your head is just egotistical i think.
No offense to anyone, i'm no expert either and i probably know less then others who have commented before me about this specifically, but i prefer to give people the benefit of a doubt when they're in a position worthy of that.

I'm not sure but I suspect the heat source (warm seawater) and heat sink (cold seawater) are a significant distance apart and that's why it's not possible to build a physical heat engine linking the two.

They tried an offshore 'pipe' system in LA years ago and found that it was cheaper to pipe the cold water directly into the heat exchangers in the buildings that wanted the AC (which is a major source of demand for electricity there.)
The temperature differences make long pipes very inefficient for energy conversion; most OTECs operate on temp differentials of just 40 degrees, and the friction in the main cold pipe uses about 30% of the available energy; extending that pipe by a factor of two would essentially destroy the advantage.
I do find it strange that everyone keeps designing sea-bed anchored plants, instead of floating, which could then go wherever the thermocline is best.
@ Araphant;
The Wright brothers invented the motorized airplane at a time when all the major industrial players were seeking exactly that kind of thing, and failing. Unlike the 'smart guys' who thought they knew all the answers, or that the science was settled, or that money would make it happen, Orville and Wilbur went back to first principles, did straight science (with their own home-made wind tunnel) on a shoestring, and succeeded.
Don't write off the amateurs so glibly; they frequently have the freedom to explore that the 'big money' doesn't, and that can make all the difference, as the Wrights proved so dramatically.
(And if you are worried about credentials; I've got a degree in astrophysics and have been studying OTEC since I first read Marshall Savage's great book "The Millennial Project" in 1998. If I had an extra $400,000, I'd float my own design approximately tomorrow.)

Hmm - in 100 years when these types of devices dot the oceans will there be concerns about reducing the temperature gradient in the ocean leading to changes in the gulf stream and other similar sub-surface flows?
Of course, by then the glacier melts could reduce the ocean's salinity by ehough to make those changes anyway, so maybe it's moot.

if this thing really does save 100 million barrels of oil per year, i like it...

Tommy: If only the Wrights had listened to the Frenchman that gave them a model of his self-stableizing craft. Instead, they assumed the stability should be supplied by the pilot. Subsequently, they warehoused the superior design that solved their most pressing problem. Three years later, a storm blew down the shed and destroyed it. Their narrow focus delayed success and resulted in the fixed wing being accepted over the rocking wing (control wing) design. The result was a century of unnecessary deaths do to stalls.
I would like to know why the OTEC plant was moved. Was it the unfriendly business atmosphere in Hawaii?