The goal of this project was to realize significant energy savings, replace old equipment, and improve reliability at this Dallas facility by converting from a glycol-water cooled DX cooling system to chilled water on one of the two mechanical loops that support the building.
Enabled Energy’s Solution
The 10 dry coolers that reject heat for Loop 1 or “The Front Loop” were replaced with three air-cooled chillers that supply chilled water at a low enough temperature year-round such that the CRACs can utilize their secondary economization coils to cool the building load.
The existing dry coolers were 19-21 years old, in disrepair, and required significant annual maintenance according to site personnel. These were replaced with new chillers with minimal modifications to the existing steel support structure and mechanical piping. Beyond the energy savings, perhaps the most important benefit of the project was the resulting reduced load on the electrical infrastructure. The value of gaining electrical switchboard capacity for the possibility of increased IT load may far outweigh the value from the energy savings, especially when considering the multi-million dollar cost it would require to increase electrical service capacity of the infrastructure at this facility. The recommissioning of the water-side system provided much needed flow to certain heavily burdened CRACs. This project also resulted in discovery and correction of a mechanical system flaw where an incorrectly sized pressure relief valve limited the ability of the system to provide adequate pumping pressure for the flow needed, especially during warm months.
This resulted in an estimated annual energy savings of 2,206,514 kWh or an average power (kW) savings of 252 kW. This equates to approximately $114,739 in annual energy expense. The PUE of the facility is expected to decrease from an annual average of 1.94 to 1.79, and when isolating the “Front Loop” only, the PUE decreased from an estimated annual average of 1.86 to 1.60 (14% improvement in PUE, and 30% improvement on non-IT usage).
Enabled Energy, Inc. performed this project in Oct/Nov 2019. Trane provided the three new chillers.