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2026 Vol.20, Issue 3 Preview Page

Research Article

Energy Performance Review of Thermal Energy Storage Combined Water-Side Economizer by ASHRAE Climate Zones

ASHRAE 기후 존별 축열조 결합형 WSE 시스템의 에너지 성능 검토

Eun-Yu Gu1
,
Seok-Ho Lim2
,
Young-Hak Song3*
구 은유1
,
임 석호2
,
송 영학3*
1Graduate Student, Graduate School, Department of Architectural Engineering, Gyeongsang National University, Jinju, Korea
2Senior Research Fellow, Department of Building and Urban Research, Korea Institute of Civil Engineering and Building Technology (KICT), Goyang, Korea
3Professor, Department of Architectural Engineering, ERI, Gyeongsang National University, Jinju, Korea
1경상국립대학교 건축공학과 대학원 석사과정
2한국건설기술연구원 건축도시연구본부 선임위원
3경상국립대학교 건축공학과 교수
*Corresponding Author
30 June 2026. pp. 223-234
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Abstract

Increased data center energy demand has raised interest in free-cooling strategies. This study evaluates a data-center cooling system that combines a thermal energy storage (TES) tank with a water-side economizer (WSE) across ASHRAE climate zones 0A–8. Using EnergyPlus annual simulations for 19 representative locations, a data-center HVAC model with the proposed TES combined WSE (TS-WSE) strategy was tested. Key results show climate-dependent performance: in cool, dry climates (e.g. ASHRAE Zone 8) the TS-WSE achieved ~83% full free cooling operation and only ~2% of full-load cooling via chillers, whereas in hot, humid climates (0A) free cooling was negligible (~0%), requiring 100% chiller cooling. Intermediate zones showed significant partial free cooling (e.g. 3B: ~56% full, ~40% partial free-cooling hours). Annual cooling demand under TS-WSE ranged from ~4,334 MWh (0A) to 653 MWh (8). These findings indicate that TS-WSE energy savings vary strongly with climate, with maximum benefit in cold, dry regions. The results underscore the importance of climate-tailored design for data-center cooling systems.

Keywords
Climate Zones
Water-side economizer
Thermal energy storage
Free cooling
Data Center
Energy performance
키워드
기후 존
외기냉수냉방
축열조
프리쿨링
데이터센터
에너지 성능
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Information
  • Publisher :Korean Institute of Architectural Sustainable Environment and Building Systems
  • Publisher(Ko) :한국건축친환경설비학회
  • Journal Title :Journal of Korean Institute of Architectural Sustainable Environment and Building Systems
  • Journal Title(Ko) :한국건축친환경설비학회논문집
  • Volume : 20
  • No :3
  • Pages :223-234
  • Received Date : 2026-05-07
  • Revised Date : 2026-05-27
  • Accepted Date : 2026-06-06
  • DOI :https://doi.org/10.22696/jkiaebs.20260019
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