New OTEC System Concept Unveiled

Global OTEC Resources has released images of its first design concepts for using ocean thermal energy conversion.

The company said it has spent the last year developing its OTEC concept especially for ‘off-grid’ resorts and local islands in the Maldives and Caribbean. The firm believes it has reached a cost model for harnessing the thermal energy from oceans comparable to, if not cheaper than, the cost of running diesel generators.

Global OTEC Resource’s concept will deliver a net capacity of 1MW of electricity to its customers across the tropics which should be enough to fully power most small-to-midsized resorts or islands.

The images show an OTEC plant housed on a floating barge which incorporates a deep cold-water pipe into its hull through a ‘weathervaning’ turret mooring system. The cold-water pipe returns seawater from a depth of 1,000m, achieving the temperature difference with the warm surface water of 20 degrees centigrade. Ammonia is repeatedly evaporated and condensed to power a turbine and produce electricity.

The turret and mooring system is designed primarily to allow the unit to align itself with incident weather conditions in order to withstand large wave heights and wind speeds, which is critical for many locations across the tropics.

The company decided to focus its design on the needs of Small Island Developing States (SIDS) after learning that many small islands consume over 10,000 litres of diesel a day. This generates a significant carbon footprint in locations that many would consider ‘idyllic’ locations for dream holidays.

Managing director, Dan Grech, said: “Many meetings with both private and public sector representatives in our target markets have indicated that currently, renewables aren’t presenting a viable proposition for islands to cut their dependence on fossil fuels. Thousands of islands lack the space for large solar and battery installations to provide their basic daily electricity loads and feel ‘stuck’ with diesel generators despite the threat climate change presents to their livelihoods.”

“Our next stage is to advance the detail of this design to be ready for fabrication. Our first ocean thermal energy systems will come online in less than two years.”

Tamara Ebanks, acting chief officer of the Ministry of Commerce, Planning and Infrastructure at the Cayman Islands Government, stated: “We believe Global OTEC Resources works are aligned with our goals of becoming a sustainable community and simultaneously achieving the United Nations Sustainable Development Goals of Affordable and Clean Energy and the Paris Agreement Targets.”

Richard Argall, leading the design of the project’s OTEC system, said: “I’ve been involved in several projects in the last decade and a half with others who have tried valiantly to get a huge OTEC developments off the ground. This project takes a sensible approach de-risking the technology, starting with small-scale niche applications like remote island communities and that gives it a huge chance of success.”