Ocean Mechanical Thermal Energy Conversion

Our oceans hold vast quantities of thermal and kinetic energy, thousands of times more than our entire civilisation requires for our current level of population. Technologies are quickly coming on line to harness this almost limitless power, and one of the most exciting breakthroughs could be Ocean Mechanical Thermal Energy Conversion, or OMTEC. This week we take a look at how it works.

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#climatechange #globalwarming #renewableenergy

[elaadt]

2 years after the video upload, can we get an update on where this project stands. Sounds very interesting.

[redpike]

I went back to school at the age of 40 to get my Bachelor of Engineering, with a double major in Marine Engineering and Naval Architecture, because I wanted to design and build OTEC power plants and plantships. I graduated in 2000, and no jobs were available to do this work, so I sailed on commercial and government ships for the next 20 years. I now teach Marine Engineering at the US Merchant Marine Academy, and would be intereestd in getting in touch with Patrick McNulty and working to move this technology forward.

[TheTEDfan]

Interesting concept. Couple tips: work out the LCOE asap. The world is not short of ways to generate renewable power. There are many competing technologies for both storage and generation. The one that will win is the lowest cost option. See the Lazard studies. For indicative costs look at structures of similar size, weight and complexity. E.g. Offshore platforms, FPSOs. Offshore everything is 2 to 5 times more expensive than onshore. Include the cost of bringing power to shore. At long distances you will need HVDC cables and related equipment. Include annual running costs of 2-4% of the investment. Mixing warm surface water and colder deeper water will result in a net reduction of heat radiation into space. So while you do cool the surface, the total planetary energy balance is negatively affected. Competitiveness of offshore wind is to a large extent driven by the length of power cables to shore. Nothing lasts forever at sea. After 25-35 years the whole thing needs expensive redevelopment or decommissioning. Those costs need to be included. To get cold water to the surface more effectively you could explore gas lift. In your current layout cold water flow will be a constraint. The density of the cold water and drag in the pipe/filters and heat exchanger may be too high. Cold water does not want to flow up. Current speed varies with depth. The bigger the pipe the larger the mechanical loads. With waves at surface the ship will want to push/pull the 600m pipe. The inertia of the pipe will result in huge structural(fatigue) forces. You may need a spar design or tension legs. But do the economics first. It has to compete on discounted lifecycle costs with other co2 neutral base load power and or variable power and storage concepts.

[macrumpton]

2020 laughs fiendishly at 2019's "looming calamities".

[Hovado_Lesni]

That water splashing is killing my ears.

[manfredstrata]

This process was used during WW2 off the coast of Africa to power radio transmitters for navigation.

[ShurahanaYume]

What impact does this have on wildlife and ecosystems?

[cautiousoptimist]

This was brilliant. I can't believe it took almost 2 years for me to stumble across it... :-)
I am now subscribed... :-)

[ronkirk]

I'm a retired mechanical engineer and find this very interesting. We're going to have to combat global warming on many fronts simultaneously and this could just be a great source of green energy. Please keep these great videos coming education is the key to solving problems.

[Paul.Gallant]

I remember a similar projet that doesn't use freon. Instead, the turbine is working in vacuum. It's the temperature difference in vacuum that creates a vapor flow that runs the turbine. The byproduct is fresh water. Probably less efficient but, it's a simpler design that does not require refrigerant.

[tomhall]

The clarity and concision of your content is refreshing. There is a growing supply of idle capital globally that rivals the accumulation of greenhouse gasses in the atmosphere. The expression of this poverty of imagination for risk taking or social responsibility is evidenced in rising rents, predatory usury, monopolization of basic industries, privatization of public assets, and the presumptive insanity that the retiring of stock shares enhances wealth in the real world. Eventually this capital will begin to flow into the most promising technologies to address the unfolding human caused environmental crisis (most promising for immediate return on investment and least threatening to established economic interests, not necessarily most promising for making progress on solving the problem). Only through government as an expression of our collective will can the locked up capital in our constipated ruling classes
be redeployed along with the near boundless potential of human capital to address what could be the existential climax that will postpone the epilogue of human civilisation.
There is no guarantee of success but our current course documents that glaciers are melting faster than our willingness to address these issues which gives new irony to the expression "glacial change".

Thanks for your indulgence.

[realvanman]

Wow, there’re all kinds of hidden gems in this channel.

[anguscampbell]

I have a question for you. If you use liquid Ammonia as a refrigerant to drive the turbines via a phase change motor or a "turbine" could that Ammonia be used as a source of H2 after it is passed through the "turbine" and then that same H2 be used to drive a Fuel Cell which also produces electricity? The reason I ask is there is a lot of hype about H2 lately and Liquid Ammonia in pressurized vessels is often tossed around as a storage medium. Since it boils at -33C it could be produced by intermittent wind or solar, stored onboard temporally as a liquid in specific pressurized tanks and then released to drive the phase change "turbines" as power is needed but with a reconfigured system to eliminate the condenser and use in a fuel cell after which the resultant gases are vented to the atmosphere.
Is this feasible? Is it economical? Does it produce enough extra electricity to justify such a system? I now working on a gravitational storage system and I am hoping to incorporate OTEC since the structure could easily accommodate such a system.

[corgraveland]

Well, the basic concept might be known following a refrigerator with condensor, evaporators and the suitable refrigerant fluid etc. But to build it in a marine vessel this way, use the speed of the gulfstream (up to 6 mph or close to 10 km/h is significant) and to add the venturi with turbine are all excellent. Thanks for sharing. Look forward to learn what next steps are. If needed can help to make some calculations.
All together, wonderful OTEC system and credits to the designers! 🌍💧⚡💡👌

[vincentanguoni]

So refreshing to hear about positive developments rather than doom and gloom.... Gracias!

[boomshotta]

This seems very promising. Any updates as we go into 2021?

[jimgraham]

Thankyou for this item. The Hawaiian OTEC system near Kona started with much the same fanfare but reality caught up.

All systems that take a low grade heat source and try to make high grade energy suffer similar problems of low efficiency and low output relative to capital expense. I am sure this proposal is well intentioned but it somewhat smacks of desperation. We need to get focused on developing real solutions (these are mostly known) to the huge challenge of powering the world in post green house gas environment.

[dogphlap]

Decades ago there was an OTEC system off Hawaii (the sea gets deep close to land there so the power cable to deliver the energy back to land was short). The problem was the ocean currents vary with depth and the shear force exerted on the long vertical tube to the cold deep water was too much for the reinforced concrete it was built with. Sorry but this latest attempt looks like a nonstarter to me. Just how far out to sea is this thing going to be located ? The water off Miami is shallow so the power cable back to shore will be long, just how long is not specified on the video which makes me think this scheme is not practicable and the instigators know it but prefer to pretend the obvious problems don't exist. One decent storm would wipe this out. As to dropping the surface temperature of the gulf to de-fuel hurricanes, good luck with that.
Oh and the 'Chemical Demilitarization Program' is actually a thing (does not sound like a real thing but it is). This from a country that is happy to use depleted uranium munitions (and don't be fooled by the word 'depleted', still 70% as radio active as naturally occurring uranium with a half life of 4.5 billion years for U-238 and 700 million years for U-235).

[christianheichel]

Never seen your channel before this movie. This movie got me to subscribe. Good content 👍

[lisaclausen]

I absolutely love this idea!!! It makes sense. It is incredible!