Patent ID: 8899061

Claim:
A cooling system comprising: a first-stage cooling assembly that comprises a forced-draft cooling tower having: an ambient air inlet, an air outlet, a cooling fluid reservoir disposed at a bottom of the first-stage cooling tower, a variable speed fan disposed adjacent to the first-stage air outlet, dedicated to the first-stage cooling tower, and configured to variably control air flow through the first-stage cooling tower, and a variable flow water pump; and a final-stage cooling assembly that comprises a forced-draft cooling tower having: an air inlet, an air outlet, a cooling fluid reservoir disposed at a bottom of the final-stage cooling tower, a variable speed fan disposed adjacent to the final-stage air outlet, dedicated to the final-stage cooling tower, and configured to variably control air flow through the final-stage cooling tower, a final-stage cooling load heat exchanger at the air inlet of the final-stage cooling tower, and a variable flow water pump that is adapted to pump cooling fluid through final-stage supply piping; wherein the first-stage variable flow water pump pumps cooling fluid from the first-stage cooling fluid reservoir through the first-stage supply piping to, and the cooling fluid from the first stage-cooling tower is in indirect heat exchange relationship with, two or more of the following heat exchangers: the final-stage cooling load heat exchanger serving the air inlet of the final-stage cooling tower; an intermediate-stage cooling load heat exchanger serving an air inlet of an optional intermediate-stage cooling tower; or a heat exchanger serving a third cooling load other than the intermediate-stage cooling load or final-stage cooling load heat exchangers; and warmed fluid is returned directly to wet media of the first-stage cooling tower and then upon being cooled flows down into the first-stage cooling fluid reservoir for reuse, and the final-stage variable flow water pump pumps cooling fluid from the final-stage cooling fluid reservoir through the final-stage supply piping to a heat exchanger serving a final cooling load and warmed fluid is returned directly to wet media of the final-stage cooling tower and then upon being cooled flows down into the final-stage cooling fluid reservoir for reuse and the cooling fluid from the final-stage cooling tower is in indirect heat exchange relationship with the heat exchanger serving the final cooling load, but the first-stage variable flow water pump does not circulate cooling fluid to an air-to-water heat exchanger servicing the ambient air inlet of the first-stage cooling tower.