We recently happened upon an article of interest, regarding the harvesting of condensation produced by HVAC systems. The concept is simple – reuse that chilled water to reduce energy expense in hot climates. For facilities that operate in areas of the country that experience average temperatures in the 90’s and relative humidity’s in the upper 70’s, this form of reclamation makes a lot of sense. It can reduce expenses, but also be significantly beneficial to the environment.
Chilled water plants are infamous for their high energy uses, both of water and of electricity. During peak demand, a chilled water plant is usually the highest user of energy. By lowering some of that usage by collecting condensate, facility operators see an immediate payback. The amount of money it would cost to pipe the condensate returns to the cooling tower will be paid back by in no time, particularly when one considers the savings on chemical treatment. The facility can re-coup that money in just a few years’ time.
Among the items that will be required for such a project are HVAC controls. Before the condensate would simply be piped to a floor drain and forgotten. Now the condensate is piped to the makeup feed system of the cooling towers. In some instances, collection tanks may be warranted depending on the application, so tank level indicators will be required to operate fill valves and transfer pumps. Pressure sensors will need to be implemented to ensure transfer pumps are working properly. If a transfer pump fails, condensate will overflow the coil drip pan, and water will be introduced into the air stream and will be allowed to soak ductwork. It could also cause the coil’s cooling capacity to plummet and, in turn, cause overheating of spaces.
These types of simple controls can be found at SRP controls. With a wide variety of tank level indicators and pressure transducers that are plug and play, this level of control is obtainable for very little cost.