Chiller controller for optimized efficiency

A system comprising:

• a chiller group including a plurality of chillers having at least one heat recovery chiller;
• one or more processors operatively coupled to the plurality of chillers;
• and
• a memory coupled to the one or more processors and including program code that, when executed by the one or more processors, causes the system to:
• determine a thermal load on the chiller group, the thermal load including a cooling load and a heating load;
• determine a current efficiency of the chiller group;
• determine an estimated efficiency of the chiller group after executing a staging operation including one of bringing an offline chiller online, taking an online chiller offline, or both bringing the offline chiller online and taking the online chiller offline, the estimated efficiency, and a lift of the chiller;
• determine an emissions caused by the chiller group based on the estimated efficiency thereof and by one or more boilers needed to satisfy the heating load;
• and
• stage the chiller group according to the staging operation by selectively activating the at least one heat recovery chiller to minimize the emissions based on emissions weighting of each energy source available to satisfy the heating load and the cooling load by calling for the most efficient quantity and order of heat recovery chillers suitable to meet both the cooling load and the heating load taking into account any contribution to the emissions by the one or more boilers and by causing the chiller group to one of bring the offline chiller online, take the online chiller offline, or both bring the offline chiller online and take the online chiller offline.

A computer program product comprising:

• a non-transitory computer-readable storage medium;
• and
• program code stored on the non-transitory computer-readable storage medium that, when executed by one or more processors, causes the one or more processors to:
• determine a thermal load on a chiller group including a plurality of chillers having at least one heat recovery chiller;
• determine a current efficiency of the chiller group;
• determine an estimated efficiency of the chiller group after executing a staging operation including one of bringing an offline chiller online, taking an online chiller offline, or both bringing the offline chiller online and taking the online chiller offline, the estimated efficiency being determined based on a relationship between a thermal transfer rate of each chiller, a parameter related to a power consumption of each chiller, and a lift of each chiller;
• determine an emissions caused by the chiller group based on the estimated efficiency thereof and by one or more boilers needed to satisfy the heating load;
• and
• stage the chiller group according to the staging operation by selectively activating the at least one heat recovery chiller to minimize the emissions based on emissions weighting of each energy source available to satisfy the heating load and the cooling load by calling for the most efficient quantity and order of heat recovery chillers suitable to meet both the cooling load and the heating load taking into account any contribution to the emissions by the one or more boilers and by causing the chiller group to one of bring the offline chiller online, take the online chiller offline, or both bring the offline chiller online and take the online chiller offline.