Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:

 

Generating energy from ocean waters off Hawaii

04.08.2010
Researchers at the University of Hawaii at Manoa say that the Leeward side of Hawaiian Islands may be ideal for future ocean-based renewable energy plants that would use seawater from the oceans' depths to drive massive heat engines and produce steady amounts of renewable energy.

The technology, referred to as Ocean Thermal Energy Conversion (OTEC), is described in the Journal of Renewable and Sustainable Energy, which is published by the American Institute of Physics (AIP).

It involves placing a heat engine between warm water collected at the ocean's surface and cold water pumped from the deep ocean. Like a ball rolling downhill, heat flows from the warm reservoir to the cool one. The greater the temperature difference, the stronger the flow of heat that can be used to do useful work such as spinning a turbine and generating electricity.

The history of OTEC dates back more than a half century. However, the technology has never taken off -- largely because of the relatively low cost of oil and other fossil fuels. But if there are any places on Earth where large OTEC facilities would be most cost competitive, it is where the ocean temperature differentials are the greatest.

Analyzing data from the National Oceanic and Atmospheric Administration's National Oceanographic Data Center, the University of Hawaii's Gérard Nihous says that the warm-cold temperature differential is about one degree Celsius greater on the leeward (western) side of the Hawaiian Islands than that on the windward (eastern) side.

This small difference translates to 15 percent more power for an OTEC plant, says Nihous, whose theoretical work focuses on driving down cost and increasing efficiency of future facilities, the biggest hurdles to bringing the technology to the mainstream.

"Testing that was done in the 1980s clearly demonstrates the feasibility of this technology," he says. "Now it's just a matter of paying for it."

More information in the project, see: http://hinmrec.hnei.hawaii.edu/ongoing-projects/otec-thermal-resource/

The article, "Mapping available Ocean Thermal Energy Conversion resources around the main Hawaiian Islands with state-of-the-art tools" by Gérard C. Nihous will appear in the Journal of Renewable and Sustainable Energy. See: http://jrse.aip.org/jrsebh/v2/i4/p043104_s1

Journalists may request a free PDF of this article by contacting jbardi@aip.org

Nihous' research is supported by the University of Hawaii's National Marine Renewable Energy Center, which is funded by the U.S. Department of Energy. See: http://hinmrec.hnei.hawaii.edu/

NOTE: Images are available for journalists. Please contact jbardi@aip.org

Image Caption #1: Average ocean temperature differences (at water depths of between 20 meters and 1000 meters depths) around the main Hawaiian Islands for the period July 1, 2007 through June 30, 2009 (the color palette is from 18°C to 24°C); the relatively more favorable area in the lee of the islands is clearly visible.

Image #1 Source/Credit: Data from HYCOM (an academia-industry consortium, see: http://www.hycom.org/ and NCODA, public data from the U.S. Navy, see: https://www.fnmoc.navy.mil/public/. Image provided by Gerard Nihous.

Image Caption #2: An example of early OTEC field work in Hawaii: aerial view of the land-based experimental open-cycle OTEC plant that operated between 1993 and 1998 on the Big Island. The facility still holds the world record for OTEC power production, with turbo-generator output exceeding 250 kW and more than 100 kW of net power exported to the grid.

Image #2 Photo credit: Luis Vega.

Audio clip portions of an interview with the researcher is also available. For more details, contact: jbardi@aip.org

JOURNAL OF RENEWABLE AND SUSTAINABLE ENERGY

Journal of Renewable and Sustainable Energy (JRSE) is an interdisciplinary, peer-reviewed journal published by the American Institute of Physics (AIP) that covers all areas of renewable and sustainable energy-related fields that apply to the physical science and engineering communities. As an electronic-only, Web-based journal with rapid publication time, JRSE is responsive to the many new developments expected in this field. The interdisciplinary approach of the publication ensures that the editors draw from researchers worldwide in a diverse range of fields. See: http://jrse.aip.org/

ABOUT AIP

The American Institute of Physics is a federation of 10 physical science societies representing more than 135,000 scientists, engineers, and educators and is one of the world's largest publishers of scientific information in the physical sciences. Offering partnership solutions for scientific societies and for similar organizations in science and engineering, AIP is a leader in the field of electronic publishing of scholarly journals. AIP publishes 12 journals (some of which are the most highly cited in their respective fields), two magazines, including its flagship publication Physics Today; and the AIP Conference Proceedings series. Its online publishing platform Scitation hosts nearly two million articles from more than 185 scholarly journals and other publications of 28 learned society publishers.

Jason Socrates Bardi | EurekAlert!
Further information:
http://www.aip.org

More articles from Power and Electrical Engineering:

nachricht Nano-scale process may speed arrival of cheaper hi-tech products
09.11.2018 | University of Edinburgh

nachricht Nuclear fusion: wrestling with burning questions on the control of 'burning plasmas'
25.10.2018 | Lehigh University

All articles from Power and Electrical Engineering >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: UNH scientists help provide first-ever views of elusive energy explosion

Researchers at the University of New Hampshire have captured a difficult-to-view singular event involving "magnetic reconnection"--the process by which sparse particles and energy around Earth collide producing a quick but mighty explosion--in the Earth's magnetotail, the magnetic environment that trails behind the planet.

Magnetic reconnection has remained a bit of a mystery to scientists. They know it exists and have documented the effects that the energy explosions can...

Im Focus: A Chip with Blood Vessels

Biochips have been developed at TU Wien (Vienna), on which tissue can be produced and examined. This allows supplying the tissue with different substances in a very controlled way.

Cultivating human cells in the Petri dish is not a big challenge today. Producing artificial tissue, however, permeated by fine blood vessels, is a much more...

Im Focus: A Leap Into Quantum Technology

Faster and secure data communication: This is the goal of a new joint project involving physicists from the University of Würzburg. The German Federal Ministry of Education and Research funds the project with 14.8 million euro.

In our digital world data security and secure communication are becoming more and more important. Quantum communication is a promising approach to achieve...

Im Focus: Research icebreaker Polarstern begins the Antarctic season

What does it look like below the ice shelf of the calved massive iceberg A68?

On Saturday, 10 November 2018, the research icebreaker Polarstern will leave its homeport of Bremerhaven, bound for Cape Town, South Africa.

Im Focus: Penn engineers develop ultrathin, ultralight 'nanocardboard'

When choosing materials to make something, trade-offs need to be made between a host of properties, such as thickness, stiffness and weight. Depending on the application in question, finding just the right balance is the difference between success and failure

Now, a team of Penn Engineers has demonstrated a new material they call "nanocardboard," an ultrathin equivalent of corrugated paper cardboard. A square...

All Focus news of the innovation-report >>>

Anzeige

Anzeige

VideoLinks
Industry & Economy
Event News

“3rd Conference on Laser Polishing – LaP 2018” Attracts International Experts and Users

09.11.2018 | Event News

On the brain’s ability to find the right direction

06.11.2018 | Event News

European Space Talks: Weltraumschrott – eine Gefahr für die Gesellschaft?

23.10.2018 | Event News

 
Latest News

Purdue cancer identity technology makes it easier to find a tumor's 'address'

16.11.2018 | Health and Medicine

Good preparation is half the digestion

16.11.2018 | Life Sciences

Microscope measures muscle weakness

16.11.2018 | Life Sciences

VideoLinks
Science & Research
Overview of more VideoLinks >>>