Demonstration of a High-Efficiency Evaporative Cooler for Improved Energy Efficiency in DoD Data Centers
Dr. Thomas Butcher | Brookhaven National
The Department of Defense (DoD) operates hundreds of data centers worldwide and energy use in this sector is growing rapidly. A significant fraction of the energy use in these facilities is for cooling. The objectives of this project are: 1) demonstration of energy savings achievable using a state-of-the art evaporative fluid cooler in tandem with existing, traditional cooling equipment in one DoD data center and 2) evaluation of alternative implementation and integration methods and potential to extend this approach across the spectrum of data center types and locations.
This project will use an indirect evaporative cooler recently developed by Munters, called the Oasis Polymer Fluid Cooler (PFC). The system is unique in that it can operate in wet and dry conditions, as conditions permit, to maximize annual energy and water savings. The Oasis PFC technology offers unique potential for applications such as data centers because, relative to other building types, they have a higher setpoint temperature, low outside air exchange rates, and lower latent cooling loads. Fluid coolers also match well with the technical trend toward liquid cooling at the server or board level. The innovative design of the Oasis PFC system minimizes the utilization of water as compared to conventional evaporative cooling devices. The use of a polymer—rather than metal—heat exchanger minimizes issues with fouling and water contamination, which simplifies water treatment and minimizes maintenance. A single packaged unit can incorporate up to four 25-ton cooling modules, for a total capacity of 100 tons. Multiple systems can be combined as needed for the required cooling load. A single four-module system, with 100 tons capacity will be demonstrated in this project. The development of the evaporative fluid cooler follows the successful development and market launch of the Munters Oasis evaporative air cooling system.
The project involves installation of the PFC system at a DoD data center in Port Hueneme, California, followed by careful monitoring and analysis to evaluate actual reduction in energy use, impact on data center temperature distribution, validation of predicted weather impacts on performance, and potential areas for improvement.
The technical target is a reduction in annual energy costs for DoD data center cooling by at least 50% with a project goal of up to 75% under favorable conditions. By integrating a state-of-the-art Oasis PFC evaporative fluid cooler in tandem with existing compressor-based systems, substantial energy savings are expected. Initial cost estimates suggest a system payback period of less than 18 months. Upon project completion, recommendations will be made to the applicability of the Oasis PFC system to other DoD data centers and buildings with high thermal loads that may enjoy similar energy savings from this technology. (Anticipated Project Completion - 2015)