seatec - Finnish marine technology review 1/2009 | Page 36

Energy-efficient air conditioning on luxury cruise vessels becoming increasingly interested in optimising the output of the air conditioning systems on their new ships. The energy-efficient and innovative air conditio- Photo: Courtesy of STX Europe Large cruise liner companies are ning technology of Royal Caribbean International’s Oasis of the Seas and Allure of the Seas, the world’s largest and most revolutionary cruise ships under construction at STX Europe’s yard in Turku for deliveries in 2009 and 2010 respectively, will be supplied by Finlandbased Koja Marine. Koja’s fan systems will be controlled by Vacon AC drives. S ince 2000, Vacon has supplied Koja Air conditioning and indoor air quality are some of the central issues affecting comfort on board luxury cruise vessels. Marine with approximately 3,500 AC drives for the control of fans in Koja’s air Vacon AC drives are silent since they conditioning systems on board some 20 require no large built-in fans, and con- luxury cruise liners – a majority of which is sequently, the air conditioning system sailing in the Caribbean. Fans often use ex- does not cause any disturbing noise. All cessive amounts of energy. Stepless speed this adds to the passenger and person- control of the fan by means of an AC drive nel comfort. can bring considerable energy savings. In The Oasis of the Seas will be the first some cases, the payback time can be as cruise liner where the Vacon AC drives are short as one year. connected to the air conditioning system More importantly, Vacon AC drives via Profibus. Fieldbus technology reduces control the temperature and the level of the amount of wiring and the number humidity in the staterooms and in the pub- of connections, the costs of installation, lic areas, thus guaranteeing better air qual- commissioning and service, and makes ity on board. On a vessel carrying thou- the system more resistant to malfunc- sands of guests, the varying need for air tions. ■ conditioning is not a problem as adjusting the Vacon AC drives according to changing needs is easy. 34 seatec 1/2009 Vacon’s scope of delivery to Koja Marine includes air-cooled AC drives up to 50 kW, mostly 380–500 V units in IP54 enclosures, providing a high degree of protection against humidity.