MODERNIZATION
COOLING THE AIR WITH THE DEEP SEA
BORA BORA, TAHITI
Photo: InterContinental Bora Bora Thalasso Resort and Spa
Before you set that hotel air conditioning thermostat lower than you would if it were your home, remember you are sharing the resources that local residents need. Is the energy that keeps the hotel cool generated by fossil fuels? Is your indulgence adding to the strain on the local energy supply? One innovative air conditioning solution in Tahiti is taking the heat off local infrastructure.
What's
changing
A tropical vacation usually requires a fair amount of air conditioning for guest comfort. In areas where energy might not be renewable or in great supply, keeping cool can have a huge effect. Innovations with ocean-based thermal energy are reducing the impact of cooling off.
What's already
possible
At the InterContinental Bora Bora Thalasso Resort and Spa, a sea water air conditioning system (SWAC) is changing how tropical hotels provide comfortable rooms for guests.
Seizing
the opportunity
The SWAC process was originally developed in Hawaii and includes pumping sea water from a depth of 3,000 feet (914 meters) to an on-shore cooling station where it travels through a titanium heat exchanger to cool a freshwater supply. The two water types never come into direct contact. The fresh water then travels on a circuit throughout the hotel to cool air and refrigerate cold storage areas. No air compressors are needed in the process.
Standout
tactic
Sea water that leaves the cooling station has another role: insulating the next batch of cold sea water. The used sea water is no longer cold, but it is not as warm as shallow ocean water. The used water returns to the ocean to a depth of 150 feet. It flows in a pipe that has the incoming cold water pipe inside. The used water insulates the cold water pipe from the even warmer shallow water that the cold water must cross to get to the cooling station.
How
it helps
The SWAC needs only 10% of the energy for running traditional air conditioning systems. In Tahiti, where energy comes from fuel oil, that saves about 660,000 gallons (2.5 million liters) of fuel per year. The system also facilitated development of unique deep sea water spa treatments at the resort. Similar systems are used in Hawaii, Hong Kong and China and could be beneficial to other regions as extreme heatwaves become more common.
Diving
deeper
While systems like SWAC save energy and have fewer negative effects in the long term, how can operators reduce the physical, short-term burden on fragile reef areas caused by installation and heavy machinery?
Increasing
impact
To help an entire coastal area save energy, groups of hotels could collaborate to build and share a single pumping system to access deep sea water, rather than having one system per hotel.
Traveling
better
Travel is inherently carbon intensive. Whether you are taking a mini-break or an annual vacation, consider ways to minimize your impact by staying longer in one place, reconsidering how you travel to the destination, and supporting businesses that are working to make their community and the world a better place.
