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Given the vital rule of data center availability and since the inlet temperature of the IT equipment increase rapidly until reaching a certain threshold value after which IT starts throttling or shut down because of overheat during cooling system failure. Hence, it is especially important to understand failures and their effects. This study presented experimental investigation and analysis of a facility-level cooling system failure scenario in which chilled water interruption introduced to the data center. Quantitative instrumentation tools including wireless technology such as wireless temperature and pressure sensors were used to measure the discrete air inlet temperature and pressure differential though cold aisle enclosure, respectively. In addition, Intelligent Platform Management Interface (IPMI) and cooling system data during failure/recovery were reported. Furthermore, the IT equipment performance and response for opened and contained environments were simulated and compared. Finally, an experiment based analysis of the Ride Through Time (RTT) of servers during chilled water interruption of the cooling infrastructure presented as well. The results showed that for all three classes of servers tested during the cooling failure, CAC helped keep the server’s cooler for longer. The containment provided a barrier between the hot and cold air streams and caused slight negative pressure to build up, which allowed the servers to pull cold air from the underfloor plenum. In addition, the results show that the effect of CAC in containment solutions on the IT equipment performance and response could vary and depend on the server’s airflow, generation and hence types of servers deployed in cold aisle enclosure. Moreover, it was shown that when compared to the discrete sensors, the IPMI inlet temperature sensors underestimate the Ride Through Time (RTT) by 42% and 12% for the CAC and opened cases, respectively.
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This content will become publicly available on February 1, 2026
Data Center Waste Heat Reuse: An Investment Analysis
Abstract A thermo-economic analysis (TEA) of a novel cooling and enhanced heat recovery (CEHR) system for data centers (DCs) is presented. Three financial metrics (net present value—NPV, return on investment—ROI, and payback period—PP) are calculated for hot and chilled water generation. Hot water generation uses vapor recompression to produce water at approximately 75 °C. Chilled water generation builds upon the hot water generation scenario by feeding the hot water stream into an absorption chiller. Without considering the additional costs for connecting the infrastructure with the customer, a payback period shorter than 2 years is found for a hot water generation system for a base case assuming a 10-MW data center (DC) in Philadelphia, PA, when carbon (reduction) credits are included. Chilled water generation is found to be economically unfavorable in this location. Sensitivities of economics to data center power, hot water versus chilled water generation, geographic region, and carbon credits are evaluated for five additional global locations in Europe and Asia. The economies of scale enable favorable payback periods for integrating hot water generation for facilities beyond 7 MW. Hot water generation is especially favorable in Singapore when replacing natural gas-based heating or hot water heat pumps.
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- Award ID(s):
- 2209691
- PAR ID:
- 10631900
- Publisher / Repository:
- ASME
- Date Published:
- Journal Name:
- ASME Journal of Engineering for Sustainable Buildings and Cities
- Volume:
- 6
- Issue:
- 1
- ISSN:
- 2642-6641
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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