Ocean thermal energy

Long before the age of sophisticated instrumentation or satellite gps systems, explorers discovered one of the most important characteristics of the oceans, the great currents that traverse them and move enormous volumes of water from one part of the planet to another. One of the best known in America and Europe is the Gulf Stream, named by and explored with only thermometers by Benjamin Franklin. The current, shown in this map, moves north along the coast of North America and then east toward northern Europe. Its discovery is often credited to Ponce de Leon. The current is so strong that sailing ships trying to sail against it (from east to west) sometimes actually traveled backwards when the winds were weak. Trips westward from Europe to North America could take two weeks longer than the eastward journey, if the navigators sailed in (against) the current instead of outside it. Due to his position with the American post office (in England) this latter observation was brought to Franklin’s attention in about 1769. He consulted a Nantucket merchant captain, Timothy Folger, who informed him about the current that was well known to colonial sailors. Franklin and Folger published this map, first in England and later in France, as an aid to sea traffic, including speedier mail delivery. Franklin followed up with experiments on his several trans-Atlantic voyages during which he measured the temperature of the ocean within and beside the current, finding that the temperature of t...

Enjoy more free content and benefits by creating an account Saving articles to read later requires an IEEE Spectrum account The Institute content is only available for members Downloading full PDF issues is exclusive for IEEE Members Access to Spectrum's Digital Edition is exclusive for IEEE Members Following topics is a feature exclusive for IEEE Members Adding your response to an article requires an IEEE Spectrum account Create an account to access more content and features on IEEE Spectrum, including the ability to save articles to read later, download Spectrum Collections, and participate in conversations with readers and editors. For more exclusive content and features, consider Join the world’s largest professional organization devoted to engineering and applied sciences and get access to all of Spectrum’s articles, archives, PDF downloads, and other benefits. This month, the Hawaii-based firm Ocean thermal energy conversion, or OTEC, is an approach to energy generation that harnesses the temperature difference between surface and deep-sea waters. It’s an energy dream that made inroads in the late 1970s and early 1980s, only to fizzle once oil prices fell. But there are some suggestions that it is again gaining momentum. Among OTEC’s attractions is that unlike other renewable energy sources, it should be capable of generating a steady stream of energy 24-7. “The utilities are excited about it because they don’t have to worry about variability,” says mechanical engine...

Tides, waves and currents can be used to produce electricity. Although still at the research and development stage and not yet commercially available, promising ocean technologies include: Wave energy, whereby converters capture the energy contained in ocean waves and use it to generate electricity. Converters include oscillating water columns that trap air pockets to drive a turbine; oscillating body converters that use wave motion; and overtopping converters that make use of height differences. Tidal energy, produced either by tidal-range technologies using a barrage (a dam or other barrier) to harvest power between high and low tide; tidal-current or tidal-stream technologies; or hybrid applications. Salinity gradient energy, arising from differing salt concentrations, as occurs where a river empties into an ocean. Demonstration projects use "pressure retarded osmosis", with freshwater flowing through a membrane to increase the pressure in a tank of saltwater; and "reverse electro dialysis" with ions of salt passing through alternating tanks of salt- and freshwater. Ocean thermal energy conversion, which generates power from the temperature difference between warm surface seawater and cold seawater at 800–1,000 metres depth. © 2011-2022 IRENA - International Renewable Energy Agency. All Rights Reserved. * The designations employed and the presentation of materials herein do not imply the expression of any opinion whatsoever on the part of the International Renewable Ene...

The Ocean Thermal Energy Association The Ocean Thermal Energy Association (OTEA) is a volunteer organization providing a means for collection, coordination, and dissemination of information for Ocean Thermal Energy Conversion (OTEC) stakeholders. The Association is transnational, non-political, and dedicated to the realization and future growth of commercial OTEC deployment. This is an association consisting of individuals with interest in the development of OTEC technology and closely related activities. Our Story Ocean Thermal Energy Conversion (OTEC) and related technologies such as seawater air conditioning (SWAC) and Deep Ocean Water (DOW) use have long been relatively unknown despite significant research and implementation around the world. Over the past 8 years, various countries have hosted the annual We now have more than 500 members and observers from 48 countries and regions. Our Executive Committee The OTEA Executive Committee (ExCo) are volunteers selected by their peers and serve two-year terms. Each Country or region with 3 or more members selects a delegate to represent them. Our ExCo, now in its second term, has a wealth of experience in academia, government, and the private sector. The OTEA logo was designed by member Endy Chaniago, Co-Founder and CTO of Supreme Technics, a Malaysian-based company that specializes in In-Water Inspection using ROV. Bylaws Our bylaws were adopted by the founding ExCo Membership in October 2020. The current version of the by...

• Article • • 25 November 2022 Growth of ocean thermal energy conversion resources under greenhouse warming regulated by oceanic eddies • • ORCID: orcid.org/0000-0002-8430-9149 • ORCID: orcid.org/0000-0002-4694-5531 • ORCID: orcid.org/0000-0003-2289-8862 • ORCID: orcid.org/0000-0002-0830-2332 • ORCID: orcid.org/0000-0001-9937-3859 • ORCID: orcid.org/0000-0001-7620-485X • … • Show authors Nature Communications volume 13, Article number: 7249 ( 2022) The concept of utilizing a large temperature difference (>20 °C) between the surface and deep seawater to generate electricity, known as the ocean thermal energy conversion (OTEC), provides a renewable solution to fueling our future. However, it remains poorly assessed how the OTEC resources will respond to future climate change. Here, we find that the global OTEC power potential is projected to increase by 46% around the end of this century under a high carbon emission scenario, compared to its present-day level. The augmented OTEC power potential due to the rising sea surface temperature is partially offset by the deep ocean warming. The offsetting effect is more evident in the Atlantic Ocean than Pacific and Indian Oceans. This is mainly attributed to the weakening of mesoscale eddy-induced upward heat transport, suggesting an important role of mesoscale eddies in regulating the response of thermal stratification and OTEC power potential to greenhouse warming. Fossil fuels as energy sources have been on heavy dependence since...