Enabled Energy was engaged to review the heat rejection equipment at five specified facilities and evaluate replacement options. Client cost for dry cooler equipment was expected to increase at the beginning of 2023, therefore it was desirable to quickly rule out alternative heat rejection options where possible and select dry coolers for replacement.
Enabled Energy was tasked to provide recommendations that might be more cost-effective, more efficient, and/or allow for more capacity in the currently allowed space.
Enabled Energy’s Solution
After receiving all data provided by the client and completing thorough reviews, Enabled Energy compiled detailed evaluations for each facility. Each evaluation took into account many various considerations, including site elevation, climate, roof space, existing dunnage systems, crane access, existing CRAC unit type, adjacency to marine, and availability of water and water storage. Additionally, ASHRAE N=10 selection criteria was used for equipment capacity considerations.
Two facilities were eliminated for consideration for alternative heat rejection equipment to dry coolers due to spacing constraints as well as considerably high cost factors (such as crane access) that would disable the desired business case outcome for any alternative options.
For the remaining three sites, fluid cooler options were initially considered but were eliminated due to water storage and usage costs. Replacing the pumps was also considered for each location, but with VFDs existing at all facilities, the proposition of new pump motors does not allow for enough energy savings to make it worthwhile from an energy savings standpoint.
Ultimately, options were presented for air-cooled chillers, dry coolers, and dry coolers with an enhanced glycol additive (HydroMX) that improves heat transfer qualities in the glycol loop. For air-cooled chillers, the client would see paybacks in 14-20 years relative to buying new dry coolers. Including the enhanced glycol additive with new dry coolers would provide paybacks in 4-7 years, significantly reducing the time required to see a return on investment.
Enabled Energy, Inc. completed these evaluations remotely in late 2022.