Curaçao seawater air-conditioning

by Thomas Bjelkeman-Pettersson, 9 July 2008

We have written previously about the seawater air-condition project by Evelop in Curaçao and a couple of weeks ago I managed to meet the Business Director of Evelop Caribbean, Gilbert Gouverneur, who is the main contractor for the project working for Aquaelectra, the local power and water company.

Schematic of seawater air conditioning system. Picture: Evelop B.V.

Curaçao is part of the Netherlands Antilles and is located just 70 kilometres north of the Venezuelan coast. It is a relatively small island, about 444 square kilometres with 138,000 inhabitants. The climate is hot and dry, which together with the good scuba diving around the island means that Curaçao has a very active tourist industry and several fairly large hotels. One of the major costs for a hotel operation is the electricity cost related to the air conditioning. The electricity in Curaçao is produced primarily with oil and with the local currency having a fixed exchange rate with the US dollar, the high oil prices really have made people sit up and notice.

The efforts to get seawater air conditioning (SWAC) in Curaçao was started in 2000, and has had Gilbert Gouverneur as the driving force behind the project since the start. The effort is now in its later stages and actual building of the pipeline and required infrastructure will begin during the autumn of 2008, with expected project completion during the summer of 2009.

Evelop has worked, among others, with the Makai Engineering, the world leaders in seawater pipes, in doing feasibility and engineering studies for the project and are engaging engineering support from sister companies within Econcern to which Evelop belongs. It will be using local contractors to build the pipeline.
The pipeline will reach 6 kilometres out into the sea, going south out from the Marriot Hotel, down to a depth of 850 meters, fetching up seawater at a temperature of 6°C at half cubic meter per second. The SWAC system operates with a temperature differential (ΔT) between the water it takes in and the water it lets out of about 7°C, and the return water will go into the sea again at 100 meters depth to avoid any substantial environmental impact.

The customers for the system are the Marriott, Hilton, Holiday Beach Hotel, Clarion hotels, as well as the World Trade Center and the Aquaelectra (local power and water company) head office.

The project is projected to cost approx. €15-20 million to complete. The investment comes from Econcerns own investment funds. The expected savings from the installation for the customers lie in the region of approx. 20-30% compared to using electricity for air conditioning. The system uses less then 10% of the energy which a traditional electric powered air conditioning system would use. Any decrease in carbon dioxide emissions and use of Freon is considered an upside (i.e. not used in the cost justification for the project).

© 2001-2008. OTEC News. All rights reserved.