Stories tagged with "otec"

Tapping The Source: The Power Of The Oceans

Last year I came across the story of Dutch company Kema and their energy island idea - basically a variant on the usual pumped hydro energy storage concept where water is pumped out of a space below sea level then allowed to flow back in, generating power as it does. The "island" uses wind power to pump water out of the enclosed area. An obvious extension to this idea would be to harness ocean energy as well - letting wave and/or tidal power supplement the output of the wind turbines. An attraction of this concept is that it potentially allows a large amount of new energy storage to be brought online - and this storage would be along the world's coastlines, where most of the population lives.

Another form of energy island has been in the news recently, this one a substantially more ambitious proposal which envisions artificial islands to collect wind, wave, ocean current and solar power in the tropics, along with a more unusual energy source - harnessing the difference in water temperatures between the warm surface and the cold depths using a technique called OTEC (Ocean Thermal Energy Conversion).

Rick Dworsky: A Warm Bath of Energy -- Ocean Thermal Energy Conversion

[editor's note, by Prof. Goose] This is a guest piece by Rick Dworsky--he has been involved in environmental conservation and energy issues for over 30 years in government and private industry.

In 1870, in Twenty Thousand Leagues Under the Sea, Jules Verne wrote: "I owe all to the ocean; it produces electricity, and electricity gives heat, light, motion, and, in a word, life to the Nautilus."

Indeed, the Earth has an enormous natural solar collector - the tropical oceans. "On an average day, 60 million square kilometers (23 million square miles) of tropical seas absorb an amount of solar radiation equal in heat content to about 250 billion barrels of oil."(1) Energy "equivalent to at least 4000 times the amount presently consumed by humans."(2) If we can tap into this renewable source, considering thermodynamics and entropy, approximately 1% of it could provide the entire current worldwide demand for energy. More than enough energy is available, we only need a way to get it - in a practical, cost effective, ecologically safe and sustainable way.

Ocean Thermal Energy Conversion (OTEC) is a technology that can extract useful work from solar energy stored in the sea. Since the sea IS the energy storage medium, OTEC offers 'always on' baseline supply -- during bright clear days and dark nights, in still air and ferocious wind storms -- without the expense and complications of artificial energy storage systems.