NSIDC Data Center: Energy Reduction Strategies - Airside Economization and Unique Indirect Evaporative Cooling (FEMP brochure, 2012)
U.S. DOE Federal Energy Management Program / National Renewable Energy Laboratory · National Renewable Energy Laboratory
This FEMP/NREL case study of the National Snow and Ice Data Center in Boulder describes a retrofit that replaced CRAC units with airside economization and multi-stage indirect evaporative coolers. It is a measured before-and-after example for small-facility retrofits.
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Overview
The study is a FEMP case study documenting the retrofit of the National Snow and Ice Data Center (NSIDC) in Boulder, prepared for DOE FEMP by a national-laboratory contractor. The retrofit replaced CRAC units with airside economization and multi-stage indirect evaporative coolers, reconfigured the room with hot-aisle containment and consolidated servers.
The multi-stage indirect evaporative units were installed in May 2011 and hot aisle containment was added. Three measures were therefore applied together: a change of cooling system, airflow reorganisation and consolidation of the IT load. Part of the results cannot be attributed to a single measure; the document presents the retrofit as a package.
According to the results, cooling energy fell by over 70% in summer months and over 90% in cooler winter months. Annual average PUE for June-October 2011 was 2.01 with the old CRAC system versus 1.55 for the new one. Since September 2011, monthly PUE has stayed below 1.35 thanks to airside economization.
As a limit, the example concerns a small facility in a dry climate. The results should not be transferred directly to humid climates or large facilities, but the case is valuable for validation.
Key points
- Cooling energy fell by over 70% in summer months and over 90% in cooler winter months.
- Annual average PUE, June-October 2011: 2.01 with the old CRAC system versus 1.55 with the new one.
- Since September 2011 monthly PUE stayed below 1.35 due to airside economization.
- Multi-stage indirect evaporative units installed in May 2011; hot aisle containment added.
- CRAC units replaced with airside economization and indirect evaporative coolers; servers consolidated.
- A retrofit of a small facility in a dry climate.
Using it in design
- Offer indirect evaporative cooling and airside economizer options in the cooling selector with climate-driven hours.
- Use the NSIDC PUE before/after as a validation case for small-facility retrofits in dry climates.
- Model hot-aisle containment and server consolidation together with the cooling-system change as a package measure.
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Who should read it
Engineers and energy efficiency consultants working on cooling retrofits and economizer selection.
Publication details
- Authors
- National Renewable Energy Laboratory
- Publisher
- U.S. DOE Federal Energy Management Program / National Renewable Energy Laboratory
- Year
- 2012
- Document language
- English
- Source type
- Government / public
- Access
- Free to read
- Licence
- Copyright retained; citation only — the publisher’s terms apply to the original document
Original licence note
Prepared for DOE FEMP by a national-laboratory contractor (stated on cover); not US-Gov public domain. Cited only.
Citation
National Renewable Energy Laboratory (2012). NSIDC Data Center: Energy Reduction Strategies - Airside Economization and Unique Indirect Evaporative Cooling (FEMP brochure, 2012). U.S. DOE Federal Energy Management Program / National Renewable Energy Laboratory. https://www.energy.gov/cmei/femp/articles/nsidc-data-center-energy-reduction-strategies
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