Efficient technologies to refresh Latin America

In most of Latin America, especially in the Caribbean, keeping locals and tourists sheltered from high temperatures has a monetary as well as an environmental price. 

Air conditioning systems, that work based mainly on fossil energies which are the most contaminating, are generating serious environmental sustainability problems such as atmospheric contamination due to the emission of greenhouse gasses which are directly  affecting the ozone layer. 

The mass consumption of air conditioning in resorts, hospitals, and homes, represents an important energy cost for countries. In fact, the use of air conditioning at a regional level represents close to 40% of the total electric energy consumed. Considering that the average price of energy in many islands of the Caribbean exceeds USD 0,30 per kW/h, energy invoices are quite high, especially for the hospitality industry.  

The good news is that the solution to this problem may be closer than expected: in the oceans that surround Latin America. 

Recent CAF studies confirm that it is possible to use deep ocean waters to generate air conditioning in some cities of the region, at a much lower cost than using conventional sources and with a positive impact on the environment. The creation of the Programa Regional de Enfriamiento Urbano (Regional Urban Cooling Program) was based on the studies, initially focused on the Caribbean, which aim to contribute to energy systems that are sustainable and efficient in all the region. 

How does it work?

These systems are relatively simple as they consist of installing tubes that go deep into the ocean, to depths of close to 1,000 meters (where the water temperature drops to 5°C) from where the water is transmitted to the cooling station. From there, the water is pumped to cool the air of commercial and hotel facilities, as well as homes that use centralized air conditioning. When the water circuit is finished, it is returned to the cooling station to be returned to the ocean.  

The so-called SWAC technology (Sea Water Air Conditioning), may be feasible in coastal areas where the ocean is close to buildings, when ocean depths reach over 800 meters, and where the demand exceeds 1,000 tons of refrigeration daily per client. Some places that could be an example for the development of this technology are:  Puerto Plata, in the Dominican Republic, and Montego Bay, in Jamaica. 

For non-coastal areas or where deep ocean waters are not available, hybrid cooling system will be implemented combining the use of temperate waters with conventional systems (chillers). In these scenarios, water may come from an external distributor, rivers, lakes that are close by, or ocean waters that are not deep, which are cooled in a central station and later sent to centers that consume air conditioning. 

To date, the results achieved show that the implementation of cooling systems is beneficial, especially for the greater consumers of electric energy resulting from the use of conventional air conditioning. 

For this reason, some years ago Finland, Sweden, Canada, the United States, and Holland included these systems in some of their building. In addition, SWAC projects have been implemented in Reunion Island, in Western Africa, and Hawaii.  

 What are the benefits? 

1. The envionment would benefit from this technology, as the adoption of urban cooling systems would reduce the emission of greenhouse gasses by approximately 30 percent, while at the same time reducing ozone-depleting substances (ODS) by 100 percent. 
2. The implementation of this technology would generate savings of up to 30 percent in electric consumption and economic costs related to the maintenance and operation of conventional air conditioning  systems, especially in hotels, airports, shopping malls, and public buildings. 
3. Maintenance costs could be reduced by 85 percent for clients, by transferring these activities to the supplier of the cooling service. 
4. The investment recovery period is calculated at 5 to 7 years, depending on the system, demand, and some factors of the economic model. 
5. It would generate positive impacts for the economy of countries, as in many islands energy needs depend on imported fossil fuels by more than 90 percent, having significant impacts on their trade balance 

As a result of the multiple benefits that the adoption of urban cooling technologies would bring to Latin America, CAF is promoting studies in Panama, the Dominican Republic, and Colombia, to analyze the possible implementation of these systems.