AWT: Salt-Based & Chemical Inhibition for Cooling Towers

Three different alternative water treatments (AWT) were evaluated at the Denver Federal Center by the National Renewable Energy Laboratory.

Two out of the three were found to

  • maintain adequate water quality,
  • lower water and sewer costs, and
  • improve chiller operations.

View full-size infographic. [PDF - 248 KB]

GPG Findings 038, December 2018, Electrochemical Cooling Tower Water Treatment. Opportunity: How much water do cooling towers use? 28%OF WATER IN COMMERCIAL BUILDINGS IS USED BY COOLING TOWERS. Technology: How does electrochemical process water treatment work? ELECTROLYSIS SEQUESTERS SCALE IN REACTOR TUBES AND CREATES CHLORINE, A NATURAL BIOCIDE. Measurement and Verification. Where did M and V occur? NATIONAL RENEWABLE ENERGY LABORATORY (NREL) assessed an alternative water treatment (AWT) system provided by Dynamic Water Technology for two 150-ton cooling towers in Savannah, Georgia. Results: How did electrochemical process water treatment perform in M&V? 32% WATER SAVINGS 99.8% reduction in blowdown. 50% MAINTENANCE REDUCTION Small cost increase in annual O&M contract. 100% CHEMICAL SAVINGS Technology generates chlorine; reduced slime. 2.5 YEAR PAYBACK @ GSA avg. water/sewer $16.76/kgal Deployment: Where does the study recommend deploying electrochemical process water treatment? CONSIDER FOR ALL COOLING TOWERS Most cost-effective in areas with high water costs or where water is excessively hard, has high pH values and/or large amounts of total dissolved solids [PDF - 248 KB]


Reference above to any specific commercial product, process or service does not constitute or imply its endorsement, recommendation or favoring by the U.S. government or any agency thereof.

Last Reviewed: 2023-01-06