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Research Article

Energy Saving Analysis of Modular Chillers: A Simulation-Based Performance Comparison with a Large Chiller

모듈형 냉동기의 에너지 절감 효과 분석: 시뮬레이션 기반 대형 냉동기 성능 비교 연구

Si-Won Park1
,
Won-Ho Jung2
,
Min-Soo Kim3
,
Je-Hyeon Lee4*
박 시원1
,
정 원호2
,
김 민수3
,
이 제헌4*
1Bachelor, Department of Refrigeration and Air-Conditioning Engineering, Pukyong National University, Busan, Korea
2Researcher, HVAC Environment Team, SHINSUNG E&G Co., Ltd, Gwacheon, Korea
3Research Fellow, Eco-Friendly Transport System Research Center, Pukyong National University, Busan, Korea
4Assistant Professor, Department of Refrigeration and Air-Conditioning Engineering, Pukyong National University, Busan, Korea
1부경대학교 에너지시스템공학부 냉동공조공학전공 학사
2㈜신성이엔지 공조환경팀 대리
3부경대학교 친환경수송시스템연구소 전임연구원
4부경대학교 에너지시스템공학부 냉동공조공학전공 조교수
*Corresponding Author
28 February 2026. pp. 38-49
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Abstract

Cooling electricity demand in office buildings is largely governed by chiller performance under part-load conditions. This study evaluates a modular chiller system against a single large chiller using an EnergyPlus model of a DOE large office with two air-cooled plants: a constant-speed chiller (993.8 kW) and a modular system of fifteen 65 kW variable-speed units (975 kW). The performance curves of the modular chillers were derived using manufacturer catalog and field measurement data, and the simulation model was calibrated to ensure an accuracy level of CV(RMSE) = 6.5% against measured power consumption. For the cooling season from May to September, with a common cooling load profile and weather file, the modular system operated at part-load ratios of 0.7~0.8 and COPs of 3.6~3.9, while the large chiller operated at 0.25~0.45 and COPs of 2.4~3.0. Total cooling electricity use of the modular system was 104.4 MWh, 24.7% lower than that of the large chiller (138.7 MWh), indicating that modular chillers can substantially reduce cooling electricity use under part-load-dominated conditions in office buildings.

Keywords
모듈형 냉동기
부분부하율
성능계수(COP)
에너지 절감
키워드
Modular chiller
Part-load ratio
coefficient of performance (COP)
Energy saving
References
1

Lee, W.-J., Kang, E.-C., Lee, E.-J., Oh, B.-C., Shin, U.-C. (2013). EA Study on the Operation Performance of Central Plant Equipment According to Part Load Characteristics. Korea Journal of Air-Conditioning and Refrigeration Engineering, 25(7), 392-397.

10.6110/KJACR.2013.25.7.392
2

Santamouris, M. (2016). Cooling the buildings – past, present and future. Energy and Buildings, 128, 617-638.

10.1016/j.enbuild.2016.07.034
3

Seo, B.M., Lee, K.H. (2016). Detailed analysis on part load ratio characteristics and cooling energy saving of chiller staging in an office building. Energy and Buildings, 119, 309-322.

10.1016/j.enbuild.2016.03.067
4

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5

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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 :1
  • Pages :38-49
  • Received Date : 2025-12-10
  • Revised Date : 2026-01-30
  • Accepted Date : 2026-02-02
  • DOI :https://doi.org/10.22696/jkiaebs.20260004
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