Federal Green Challenge
Comparing Non-Traditional Water Treatment in Cooling Towers
Who: General Services Administration (GSA) Region 8, Department of Energy/National Renewable Energy Laboratory (DOE/NREL).
Where: Lakewood, Colorado
Background: Cooling towers, which are installed in many federal buildings, consume large amounts of potable water and contribute greatly to annual utility, maintenance and operation costs. Conventional cooling towers require that chemicals and fresh water is periodically added to the cooling tower water to prevent scale formulation, hinder biological growth, and inhibit corrosion in the chillers and piping systems. This project analyzes several non-chemical cooling tower water treatment systems that, potentially, can reduce GSA building operation costs through decreased water and chemical costs and improved chiller energy efficiency.
Between 2010 and 2012, GSA Region 8, in collaboration with DOE’s National Renewable Energy Lab and Denver Water, installed pilot water treatment systems on three cooling towers located at GSA leased buildings, where the primary tenants were U.S. Environmental Protection Agency, U.S. Geological Survey, and the Bureau of Reclamation.
What will happen in 2013: Early results indicate that two of the three pilot technologies are successful in accomplishing water and energy conservation goals. For example, one of the technologies reduced water use by 1.1 million gallons over a single summer in one cooling tower. Therefore, GSA recently initiated an in-depth four month study to evaluate the performance of all three pilot water treatment systems. The in-depth review aims to understand the conditions necessary for technology application and determine the potential to scale-up from a pilot phase and replicate nontraditional water treatment technologies in federal buildings nationwide.
Relevance to Executive Order 13514: Reducing building energy intensity and water use. Implementation of nontraditional cooling tower water treatment also has the potential to be part of an energy savings performance contracts.
Learn more about Comparing Non-Traditional Water Treatment Cooling Towers (PDF) (46 pp, 1.6M)