Wednesday, November 25, 2009

Hot Dollars from Cold Water (to cool climate)

Small Island states are being urged to harness the power of the oceans for their energy needs by innovation experts who are using cutting edge technologies. "We're talking about using cold sea water to make hard cash," says Lelei TuiSamoa LeLaulu, president of SOS Caribe, earlier this year in the Dominican Republic

He is referring to sea water air conditioning (SWAC) and a similar technology, ocean thermal energy conversion (OTEC), which generates energy by harnessing the difference between deep ocean water and warmer surface water. The basic technology was pioneered in Hawaii by Wes Craven of the Natural Energy Laboratory of Hawaii founded in 1974 -

Closer to home, Mauritius, in an "island style" triple bottom line approach, will be using SWAC to meet the challenges of globalisation by becoming an international data centre, dramatically cut costs of cooling equipment needed for such centers, AND reduce its carbon foortprint. It is putting in place huge computer servers that will enable the country to become a major hub for holding, analyzing and transmitting huge amounts of electronic data.

At the same time it is building an eco-park with technology to pump seawater from nearly 2000 meters down and cool the servers. The main cost issue in all modern data centers is power for daily operations and importantly to cool the racks of servers which need to dissipate heat. The energy needed for pumping the water is far less, by orders of magnitude, than if the stacks were cooled using conventional systems, say experts working on the project.

Three data centers are already running. According to experts the SWAC water-cooled system of Mauritius will be larger than any of the existing systems elsewhere. The Mauritius Board of Investment is confident that their approach and technology will allow the country to leapfrog in key areas. In fact, the physical location of Mauritius near deep ocean gives it a natural competitive advantage in the use of such technology. This water from the depths also has lots of other applications such as hydrotherapy, say enthusiastic entrepreneurs.

Mauritius believes adoption of SWAC technology is the right move at the right time. This is the time when many governments and companies are preoccupied with global warming and their own contribution to it. In addition, power costs are a major barrier to competitiveness in many types of industries. And, for small island states the fuel bill is always at the highest rung of the national budget.

Imported fuel is crippling many small island states and most are actively seeking alternative means for power generation. "It does not make sense to import expensive, dirty oil from thousands of miles away when the ocean surrounding us can give us our energy " asserts LeLaulu.

Mauritius may have chosen a financially sustainable route because it is a commercial need (holding and routing that most valuable of assets - data) that is driving and financing green technology. Without that aggressive business model much of the capital investment needed for large scale green energy operations may be out of reach of most small states. This is exactly the dilemma that Maldives, with its carbon neutral aspirations, is currently having

However, take note. In the further reaches of the Indian Ocean at the US military base of Diego Garcia in the Chagos archipelago, Ocean Engineering and Energy Systems (OCEES) of Hawaii ( with Ocean Thermal Energy Conversion Systems Ltd. from the UK have been in development of the final plans for an OTEC power plant so as to make the military base independent of fuel supplies. Peter Sand, the author of a recent book on Diego Garcia who gave me the details of this project, tells me that the plant is supposed to be bankrolled by a consortium of European banks and is to supply 8 megawatts of electricity, with sufficient power to desalinate 4.73 million litres of seawater per day and to provide seawater air-conditioning. The fesibility study was done in 1996 and an environmental impact assessment published in 2001..


Islander said...

"In the further reaches of the Indian Ocean at the top secret base of Diego Garcia in the Chagos archipelago Ocean Engineering and Energy Systems of Hawaii is building an OTEC power plant for the US naval base stationed there....."

This misinformation is becoming widespread on the internet. The truth is that the US Navy is working with a contractor to to design such a system. Nothing has been built at Diego Garcia. This study is all there is, and nothing has been released about it.

Nirmal Jivan Shah said...

According to the U.S. Navy's Fiscal Year 2006 Annual Energy Management Report (p. 16), phase III of the project "is moving forward with support from the U.S. and British commands", and at that time was expected to be up and running by the end of 2011; see also the testimony of Wayne Arny, Deputy Undersecretary of Defense for Installations and Environment, before the Subcommittee on Readiness of the U.S. House of Representatives' Armed Services Committee (13 March 2008, p. 7). The initial feasibility study was written in 1996 by Hans J. Krock (University of Hawaii at Manoa), Ocean Thermal Energy Conversion Feasibility Study for the Navy: Report to U.S. Naval Facilities Engineering Command, under Contract No. N4708-94-D-1038, D.O. 0014.
Peter H. Sand, author of United States and Britain in Diego Garcia. The Future of a Controversial Base. Palgrave Macmillan