United States. The U.S. Defense Commissioner's Agency (DeCA) is trying to increase its adoption of CO2 cooling systems after the successful installation of a cascade system in a store in San Antonio, Texas.
The 35,000-square-meter precinct in San Antonio, Texas, which supplies Lackland Air Force Base, recently converted its R404A system to an ammonia/CO2 cascade system. The previous cooling system, which contained around 3,200kg of R404A was over 13 years old and ready for retirement.
The remodeling of the store began in January 2014 and is expected to be completed this month. The installation of the cooling system was completed in December 2014. As part of the remodeling, all cases, pipes, controls, and HVAC system were also replaced. The store remained open to the public throughout the process.
DeCA chose to adopt the ammonia/CO2 cascade system to achieve the energy and sustainability goals set by the U.S. Government for all public buildings. A transcritical CO2 system was considered, but, due to the warm climate of South Texas, the cascade system was considered the most suitable.
In total, the system has a low-capacity temperature of 90 kW/h and an average temperature cooling capacity of 360kw/h. The system consists of nine ammonia modules, each containing 4kg of refrigerant, as well as approximately 816kg of CO2.
DeCa is an agency of the U.S. Department of Defense, operating more than 245 police stations around the world, selling groceries and household items to U.S. soldiers and their families.
