Ocean Thermal Energy Conversion: From temperature differences between surface and deep ocean waters

By Fouad Sabry

What Is Ocean Thermal Energy Conversion

Ocean Thermal Energy Conversion (OTEC) is a process that makes use of the temperature difference that exists in the ocean between the deeper, cooler waters and the warmer, shallower or surface waters in order to power a heat engine that generates useful work, most commonly in the form of electricity. OTEC is able to function with a capacity factor that is very high, and as a result, it is able to function in base load mode.

How You Will Benefit

(I) Insights, and validations about the following topics:

Chapter 1: Ocean thermal energy conversion

Chapter 2: Heat engine

Chapter 3: Power station

Chapter 4: Combined cycle power plant

Chapter 5: Rankine cycle

Chapter 6: Cogeneration

Chapter 7: Chiller

Chapter 8: Deep ocean water

Chapter 9: Thermal power station

Chapter 10: Solar desalination

Chapter 11: Surface condenser

Chapter 12: Binary cycle

Chapter 13: Steam-electric power station

Chapter 14: Osmotic power

Chapter 15: Transcritical cycle

Chapter 16: Deep water source cooling

Chapter 17: Mist lift

Chapter 18: Evaporator (marine)

Chapter 19: Low-temperature thermal desalination

Chapter 20: Copper in heat exchangers

Chapter 21: Low-temperature distillation

(II) Answering the public top questions about ocean thermal energy conversion.

(III) Real world examples for the usage of ocean thermal energy conversion in many fields.

(IV) 17 appendices to explain, briefly, 266 emerging technologies in each industry to have 360-degree full understanding of ocean thermal energy conversion' technologies.

Who This Book Is For

Professionals, undergraduate and graduate students, enthusiasts, hobbyists, and those who want to go beyond basic knowledge or information for any kind of ocean thermal energy conversion.

• Language: English
• Publisher: One Billion Knowledgeable
• Release date: Oct 15, 2022

Book preview

Copyright

Ocean Thermal Energy Conversion Copyright © 2022 by Fouad Sabry. All Rights Reserved.

All rights reserved. No part of this book may be reproduced in any form or by any electronic or mechanical means including information storage and retrieval systems, without permission in writing from the author. The only exception is by a reviewer, who may quote short excerpts in a review.

Cover designed by Fouad Sabry.

This book is a work of fiction. Names, characters, places, and incidents either are products of the author’s imagination or are used fictitiously. Any resemblance to actual persons, living or dead, events, or locales is entirely coincidental.

Bonus

You can send an email to [e-mail] with the subject line Ocean Thermal Energy Conversion: From temperature differences between surface and deep ocean waters, and you will receive an email which contains the first few chapters of this book.

Fouad Sabry

Visit 1BK website at

www.1BKOfficial.org

Preface

Why did I write this book?

The story of writing this book started on 1989, when I was a student in the Secondary School of Advanced Students.

It is remarkably like the STEM (Science, Technology, Engineering, and Mathematics) Schools, which are now available in many advanced countries.

STEM is a curriculum based on the idea of educating students in four specific disciplines — science, technology, engineering, and mathematics — in an interdisciplinary and applied approach. This term is typically used to address an education policy or a curriculum choice in schools. It has implications for workforce development, national security concerns and immigration policy.

There was a weekly class in the library, where each student is free to choose any book and read for 1 hour. The objective of the class is to encourage the students to read subjects other than the educational curriculum.

In the library, while I was looking at the books on the shelves, I noticed huge books, total of 5,000 pages in 5 parts. The books name is The Encyclopedia of Technology, which describes everything around us, from absolute zero to semiconductors, almost every technology, at that time, was explained with colorful illustrations and simple words. I started to read the encyclopedia, and of course, I was not able to finish it in the 1-hour weekly class.

So, I convinced my father to buy the encyclopedia. My father bought all the technology tools for me in the beginning of my life, the first computer and the first technology encyclopedia, and both have a great impact on myself and my career.

I have finished the entire encyclopedia in the same summer vacation of this year, and then I started to see how the universe works and to how to apply that knowledge to everyday problems.

My passion to the technology started mor than 30 years ago and still the journey goes on.

This book is part of The Encyclopedia of Emerging Technologies which is my attempt to give the readers the same amazing experience I had when I was in high school, but instead of 20th century technologies, I am more interested in the 21st century emerging technologies, applications, and industry solutions.

The Encyclopedia of Emerging Technologies will consist of 365 books, each book will be focused on one single emerging technology. You can read the list of emerging technologies and their categorization by industry in the part of Coming Soon, at the end of the book.

365 books to give the readers the chance to increase their knowledge on one single emerging technology every day within the course of one year period.

Introduction

How did I write this book?

In every book of The Encyclopedia of Emerging Technologies, I am trying to get instant, raw search insights, direct from the minds of the people, trying to answer their questions about the emerging technology.

There are 3 billion Google searches every day, and 20% of those have never been seen before. They are like a direct line to the people thoughts.

Sometimes that’s ‘How do I remove paper jam’. Other times, it is the wrenching fears and secret hankerings they would only ever dare share with Google.

In my pursuit to discover an untapped goldmine of content ideas about Ocean Thermal Energy Conversion, I use many tools to listen into autocomplete data from search engines like Google, then quickly cranks out every useful phrase and question, the people are asking around the keyword Ocean Thermal Energy Conversion.

It is a goldmine of people insight, I can use to create fresh, ultra-useful content, products, and services. The kind people, like you, really want.

People searches are the most important dataset ever collected on the human psyche. Therefore, this book is a live product, and constantly updated by more and more answers for new questions about Ocean Thermal Energy Conversion, asked by people, just like you and me, wondering about this new emerging technology and would like to know more about it.

The approach for writing this book is to get a deeper level of understanding of how people search around Ocean Thermal Energy Conversion, revealing questions and queries which I would not necessarily think off the top of my head, and answering these questions in super easy and digestible words, and to navigate the book around in a straightforward way.

So, when it comes to writing this book, I have ensured that it is as optimized and targeted as possible. This book purpose is helping the people to further understand and grow their knowledge about Ocean Thermal Energy Conversion. I am trying to answer people’s questions as closely as possible and showing a lot more.

It is a fantastic, and beautiful way to explore questions and problems that the people have and answer them directly, and add insight, validation, and creativity to the content of the book – even pitches and proposals. The book uncovers rich, less crowded, and sometimes surprising areas of research demand I would not otherwise reach. There is no doubt that, it is expected to increase the knowledge of the potential readers’ minds, after reading the book using this approach.

I have applied a unique approach to make the content of this book always fresh. This approach depends on listening to the people minds, by using the search listening tools. This approach helped me to:

Meet the readers exactly where they are, so I can create relevant content that strikes a chord and drives more understanding to the topic.

Keep my finger firmly on the pulse, so I can get updates when people talk about this emerging technology in new ways, and monitor trends over time.

Uncover hidden treasures of questions need answers about the emerging technology to discover unexpected insights and hidden niches that boost the relevancy of the content and give it a winning edge.

The building block for writing this book include the following:

(1) I have stopped wasting the time on gutfeel and guesswork about the content wanted by the readers, filled the book content with what the people need and said goodbye to the endless content ideas based on speculations.

(2) I have made solid decisions, and taken fewer risks, to get front row seats to what people want to read and want to know — in real time — and use search data to make bold decisions, about which topics to include and which topics to exclude.

(3) I have streamlined my content production to identify content ideas without manually having to sift through individual opinions to save days and even weeks of time.

It is wonderful to help the people to increase their knowledge in a straightforward way by just answering their questions.

I think the approach of writing of this book is unique as it collates, and tracks the important questions being asked by the readers on search engines.

Acknowledgments

Writing a book is harder than I thought and more rewarding than I could have ever imagined. None of this would have been possible without the work completed by prestigious researchers, and I would like to acknowledge their efforts to increase the knowledge of the public about this emerging technology.

Dedication

To the enlightened, the ones who see things differently, and want the world to be better -- they are not fond of the status quo or the existing state. You can disagree with them too much, and you can argue with them even more, but you cannot ignore them, and you cannot underestimate them, because they always change things... they push the human race forward, and while some may see them as the crazy ones or amateur, others see genius and innovators, because the ones who are enlightened enough to think that they can change the world, are the ones who do, and lead the people to the enlightenment.

Epigraph

Ocean Thermal Energy Conversion (OTEC) is a process that makes use of the temperature difference that exists in the ocean between the deeper, cooler waters and the warmer, shallower or surface waters in order to power a heat engine that generates useful work, most commonly in the form of electricity. OTEC is able to function with a capacity factor that is very high, and as a result, it is able to function in base load mode.

Table of Contents

Copyright

Bonus

Preface

Introduction

Acknowledgments

Dedication

Epigraph

Table of Contents

Chapter 1: Ocean thermal energy conversion

Chapter 2: Desalination

Chapter 3: Power station

Chapter 4: Combined cycle power plant

Chapter 5: Rankine cycle

Chapter 5: Cogeneration

Chapter 7: Chiller

Chapter 8: Deep ocean water

Chapter 9: Thermal power station

Chapter 10: Solar desalination

Chapter 11: Surface condenser

Chapter 12: Binary cycle

Chapter 13: Steam-electric power station

Chapter 14: Osmotic power

Chapter 15: Transcritical cycle

Chapter 16: Deep water source cooling

Chapter 17: Energy development

Chapter 18: Mist lift

Chapter 19: Evaporator (marine)

Chapter 20: Low-temperature thermal desalination

Chapter 21: Low-temperature distillation

Epilogue

About the Author

Coming Soon

Appendices: Emerging Technologies in Each Industry

Chapter 1: Ocean thermal energy conversion

Ocean Thermal Energy Conversion (OTEC) is a process that makes use of the temperature difference that exists in the ocean between the deeper, cooler waters and the warmer, shallower or surface waters in order to power a heat engine that generates useful work, most commonly in the form of electricity. OTEC is able to maintain a very high capacity factor, and as a result, it is able to function in base load mode.

The denser cold water masses that are produced as a result of the interaction of ocean surface water with cold atmosphere in quite specific regions of the North Atlantic and the Southern Ocean sink into the deep sea basins and are distributed throughout the entire deep ocean by the thermohaline circulation. The replenishment of the upwelling of cold water from the depths of the ocean comes from the downwelling of cold water from the top of the sea.

OTEC is one of the constantly accessible renewable energy resources that might contribute to base-load power supply. This makes it one of the ocean energy sources that OTEC represents.

Both open-cycle and closed-cycle configurations are possible for systems. Working fluids in a closed-cycle OTEC are often considered of as refrigerants, and some examples of these fluids are ammonia and R-134a. As a result of their low boiling temperatures, these fluids are ideal for use in the system's generator, which is responsible for the generation of energy. The Rankine cycle, which makes use of a low-pressure turbine, is now the kind of heat cycle for OTEC that is used the most often. The vapor that is produced from the ocean itself is used by open-cycle engines as the operating fluid.

As an additional by-product, OTEC is able to provide large volumes of cold water. This can be put to use for things like air conditioning and refrigeration, and the water from the deep ocean, which is rich in nutrients, may be utilized to feed biological technology. Seawater that has been distilled to produce fresh water is yet another byproduct.

In the 1880s, people first began making attempts to create and perfect OTEC technology. In the year 1881, a French scientist named Jacques Arsene d'Arsonval presented the idea of harnessing the thermal energy of the ocean. Georges Claude, a pupil of D'Arsonval's, constructed the very first OTEC plant in Matanzas, Cuba, in the year 1930. (The total quantity of power created is known as the system's net power after the amount of electricity required to operate the system has been subtracted.).

In 1956, researchers from France developed a three megawatt plant specifically for the city of Abidjan in Ivory Coast. The facility was never finished because subsequent discoveries of vast volumes of relatively inexpensive petroleum rendered its completion uneconomical. In 1981, a significant step forward was taken in the development of OTEC technology when a Russian engineer by the name of Dr. Alexander Kalina employed a combination of ammonia and water to generate energy. The effectiveness of the power cycle was significantly boosted by the use of this unique ammonia-water combination. In 1994, Saga University planned and built a 4.5 kW plant for the purpose of testing a newly devised Uehara cycle, also called after its creator Haruo Uehara. The goal of the plant was to test the Uehara cycle, which was also named after its developer. This system's performance is superior to that of the Kalina cycle by 1-2 percent because to the inclusion of absorption and extraction processes in this cycle. The Institute of Ocean Energy at Saga University is now the leader in OTEC power plant research. In addition, the Institute works on many of the secondary advantages that are associated with the technology.

During the 1970s, there was an increase in OTEC research and development during the period after the Arab-Israeli War in 1973, which caused the price of oil to quadruple. After President Carter signed a statute that committed the United States to a production target of 10,000 MW of power from OTEC systems by the year 1999, the federal government of the United States invested a total of 260 million dollars in OTEC research.

At Keahole Point, which is located on the Kona coast of Hawaii, the United States government created the Natural Energy Laboratory of Hawaii Authority (NELHA) in 1974. Because of its warm surface water, access to extremely deep and very cold water, and expensive power, Hawaii is the finest site in the United States for an OTEC facility. The testing center has established itself as one of the most reputable for OTEC technology. 1979 saw the production of a negligible quantity of power over a period of three months.

An effort coming from Europe Between the years 1979 and 1983, EUROCEAN, a privately financed joint venture consisting of nine European businesses that were already engaged in offshore engineering, was involved in the promotion of OTEC.

At first, the feasibility of a large-scale offshore plant was investigated.

Later on, a land-based system with a capacity of 100 kW that combines OTEC with desalination and aquaculture and is referred to as ODA was the subject of research.

This was determined based on the findings of a small-scale aquaculture facility located on the island of St. Croix. This facility made use of a deepwater supply line in order to feed its aquaculture basins.

Also examined was the possibility of a land-based open cycle plant.

The location of the case of study was the Dutch Kingdom related island Curaçao.).

This design included the whole of the cycle's components, namely, the evaporator, combined the condenser and turbine into a single vacuum vessel, with the turbine being positioned above the structure to exclude any possibility of water getting into it.

Concrete was used in the construction of the vessel, which was the first of its type to be a process vacuum vessel.

It was not possible to manufacture all of the components out of a low-cost plastic material, despite the efforts made, due to the fact that the turbine and the vacuum pumps that were created as the first of their type needed some degree of caution.

Later Dr.

Bharathan continued to develop this concept through both the preliminary and final phases of the process with the assistance of a group of engineers working at the Pacific Institute for High Technology Research (PICHTR).

It was later rebranded as the Net Power Producing Experiment (NPPE), and it was built at the Natural Energy Laboratory of Hawaii (NELH) by PICHTR. Chief Engineer Don Evans headed the team that worked on the project, while Dr. Xiaoping Zhang oversaw it as the project manager.

Luis Vega.

In 2002, India conducted experiments at a 1 MW floating OTEC pilot plant located in the vicinity of Tamil Nadu. The collapse of the deep sea cold water line finally led to the plant's inability to produce any useful output. At that point, it is anticipated that work on the SWAC system would get back up again.

At the Natural Energy Laboratory of Hawaii, Makai Ocean Engineering completed the design and building of an OTEC Heat Exchanger Test Facility in July of 2011. The objective of the facility is to develop an ideal design for OTEC heat exchangers, with the goals of improving performance and extending usable life while simultaneously lowering costs (heat exchangers are the primary factor in an OTEC plant's total operating expenses).

The construction of a new OTEC facility at Saga University was finished in March of 2013, with assistance from a variety of Japanese firms. On April 15, 2013, Okinawa Prefecture made the announcement that testing for the OTEC operation will begin the following day on Kume Island. The primary objective is to exhibit OTEC to the general audience while also demonstrating the accuracy of computer models. Up to the conclusion of the fiscal year 2016, the testing and research will continue to be carried out with the help of Saga University. The Okinawa Prefecture Deep Sea Water Research Center tasked IHI Plant Construction Co. Ltd, Yokogawa Electric Corporation, and Xenesys Inc. with the task of building a 100 kilowatt class plant on the grounds of the facility. The site was particularly selected so that the research facility could make use of the deep seawater and surface seawater intake pipelines that had been erected in 2000 for the purposes of the research facility. The pipe is put to use to bring in water from the depths of the ocean for the purposes of research, fishing, and farming. [19] The plant is made up of two 50 kW units that are configured in a double Rankine fashion. At the moment, there are just two OTEC facilities anywhere in the globe that are running at full capacity. This facility runs without interruption even when there aren't any particular testing going on.

2011 saw the completion of a heat exchanger test facility that was located at NELHA by Makai Ocean Engineering. The installation of a 105 kW turbine on Makai has been made possible thanks to financing from OTEC. This turbine will be used on Makai to test a range of heat exchange methods. The installation of this facility will make it the biggest OTEC facility now in operation; nevertheless, the record for greatest power will continue to be held by the Open Cycle plant that was also created in Hawaii.

In July of 2014, the DCNS group and Akuo Energy made the announcement that they will be receiving NER 300 financing for their NEMO project. If all goes according to plan, the 16MW gross/10MW net offshore plant will be OTEC's most powerful facility to date. NEMO is expected to be fully operational for DCNS by the year 2020.

When operated in an environment with a significant temperature gradient, a heat engine achieves higher levels of efficiency.

The tropics have the largest temperature gap between the surface and the deeper waters of the seas, although still a modest 20 to 25 °C.

As a result, the tropics are the regions in which OTEC presents the highest number of opportunities.

Performance may now come close to reaching the theoretical maximum thanks to modern designs. The efficiency of Carnot.

The OTEC systems that may be broken down into three categories are closed-cycle, open-cycle, and hybrid. Each of these categories uses cold seawater as an essential component. In order for the system to function, the cold water from the ocean has to be delivered to the surface. Active pumping and desalination are the two basic methods that are used. The process of desalinating saltwater close to the sea bottom causes the density of the water to decrease, which in turn leads it to rise to the surface.

Fluids having a low point of boiling are used in closed-cycle systems, such as ammonia (having a boiling point around -33 °C at atmospheric pressure), to provide the necessary force to turn a turbine and produce energy.

The fluid is vaporized by passing warm surface seawater via a heat exchanger, which is pushed through continuously.

The turbo-generator gets its power from the expanding vapor.

Cold water, circulated via a second heat exchanger by pumping, condenses the vapor into a liquid, It is subsequently distributed throughout the system through recycling.

The Natural Energy Laboratory and many partners from the corporate sector collaborated in 1979 to build the small OTEC experiment, which resulted in the first successful generation of net electrical power from closed-cycle OTEC while taking place at sea. The tiny OTEC sailboat was anchored around 1.5 miles (2.4 kilometers) off the coast of Hawaii, and it generated sufficient net energy to power the ship's light bulbs, as well as its computers and television.

Open-cycle OTEC generates power by using warm water from the surface directly. First, the warm saltwater is poured into a container with low pressure, which brings about the boiling point of the water. In a few different configurations, the expanding vapor powers a low-pressure turbine that is connected to an electrical generator. The vapor is fresh water in its purest form; the low-pressure container is where the salt and other impurities have been left behind by the vapor. Because of the low temperatures in the deep ocean, it is able to become a liquid after being exposed to these conditions. This process generates desalinized fresh water, which may be used for many purposes including aquaculture, irrigation, and drinking.

A hybrid cycle incorporates aspects of both the open-cycle and closed-cycle energy transfer systems. In a hybrid system, warm seawater is forced into a vacuum chamber before being subjected to a flash evaporation process, which is analogous to the open-cycle evaporation method. On the opposite side of an ammonia vaporizer, where the steam enters, the ammonia working fluid of a closed-cycle loop is vaporized by the steam. After being vaporized, the liquid then turns a turbine, which results in the production of energy. The heat exchanger causes the steam to condense, which results in the production of desalinated