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What is it?

The Collective Protection System (CPS) is a full-time air filtration system that is integrated into a ship’s HVAC system. It creates pressurization in some areas that will push air outwards in the event of a chemical outbreak. However, the current CPS was not designed for energy efficiency.

How does it work?

The amount of outside supply air delivered to CPS zones varies with filter loading over time and is almost always higher than needed, resulting in an above average HVAC load.  Additionally, the filtered and conditioned air is continuously purged through multiple airlocks and decontamination stations.  With the recent availability of air flow control components like Variable Speed Drives (VSD), it is possible to reduce the energy burden of CPS by maintaining a constant supply air flow rate and reducing purge flow when it is not needed.

What will it accomplish?

VSDs will be used to control CPS supply fans to optimize supply air flow so that energy savings from fan motors and reduced HVAC loads can be realized.