Energy-cost analysis of HVAC system for office buildings: Development of a multiple prediction methodology for HVAC system cost estimation

Cho, Jinkyun,Kim, Yundeok,Koo, Junemo,Park, Woopyeng Elsevier 2018 Energy and buildings Vol.173 No.-

<P><B>Abstract</B></P> <P>Buildings targeted at high energy performance levels have been proven to be technically feasible, but are relatively expensive. This research examined the cost relationship between sub-systems of HVAC (Heating, Ventilation and Air Conditioning) for energy efficient buildings. <I>Because of</I> inadequate information to estimate investment cost of HVAC systems in the early stage of building projects, this study was carried out the cost analysis method in the process of formulating predictive models for cost of HVAC systems. The relationship between the variables in the cost estimation was examined with the use of descriptive statistics and multiple correlation analysis. One of the major findings of the research was that the cost of HVAC systems of any given office building project can be assessed from the same building conditions with <I>high</I> confidence limits using multiple matrix models of HVAC sub-systems and this provided a basis for developing 960 cost models. There is potentially large variability in the range −26–460% with an average at 179% in investment costs for the sub-systems. The cost of a HVAC system has a range of about 125–335 unit rate, which represents a variety of system combinations. Decision tree analysis of energy performance and investment cost of HVAC systems were obtained, yielding information on optimal combination HVAC sets in the office buildings.</P> <P><B>Highlights</B></P> <P> <UL> <LI> We examined the cost relationship between sub-systems of HVAC for energy efficient buildings. </LI> <LI> The method for predicting the investment cost of the possible 960 combinations of HVAC system was suggested. </LI> <LI> The design rules to optimize the energy-cost level for HVAC system were investigated. </LI> <LI> The effects of the HVAC design factors of investment cost on the energy performance were analyzed quantitatively. </LI> <LI> The air conditioning system, sub-system of HVAC was found to be the most significant design factor. </LI> </UL> </P>

스마트시티 데이터허브를 활용한 공조시스템용 에너지소비량 절감 알고리즘 개발

김성중(Sung Joong Kim),추연욱(Yeon Ouk Choo),송영국(Youngkook Song),윤용태(Yong-tae Yoon),김경훈(Kyoung-hoon Kim) 한국콘텐츠학회 2023 한국콘텐츠학회논문지 Vol.23 No.3

공기조화시스템은 건물 내 공기의 질을 이용자들의 활동에 쾌적하도록 유지해주는 기술 일체를 뜻한다. 대형 건축물의 중앙식 공조시스템은 미리 설계된 매뉴얼에 맞추어 단순하게 운영되기에, 건물에너지의 낭비를 초래하고, 실내 공기질 개선 등 이용자의 요구사항 반영에도 난점을 지닌다. 다양한 도시 데이터를 바탕으로 시민 삶의 질 향상을 목표로 하는 스마트시티와 데이터허브의 도입은 기존 공기조화시스템 개선의 동력이 될 수 있다. 본 논문은 페르소나 기법을 활용하여 테스트 건물인 서울대학교 시흥캠퍼스 교육협력동 이용자들의 니즈를 파악하고, 스마트시티 데이터허브의 데이터를 활용하는 공조시스템 실시간 운영 알고리즘을 제시한다. 알고리즘은 건물 내외 이산화탄소 농도, 미세먼지 농도, 온습도를 비교하여 공조시스템의 댐퍼 개도를 실시간으로 조절한다. 새로운 알고리즘은 공조시스템의 연간 에너지소비량을 기존 대비 32% 절감하고, 실내 미세먼지 및 이산화탄소 농도 또한 이용객의 쾌적 활동범위에서 유지한다. The HVAC system maintains the quality of air in the building to be comfortable for the inhabitants. As the HVAC system for large buildings has usually been operated manually, it has weaknesses in efficient use of energy and reflecting inhabitants’ needs such as air quality improvement. Development of smart city and data hubs, aimed at improving the quality of life of citizens based on various city data, can become a driving force in improving the conventional HVAC system. By using the persona technique, this paper identifies the needs of inhabitants of the test-bed building in Seoul National University and suggests algorithm that run the HVAC system in real-time using data collected through the smart city data hub. The algorithm is designed to adjust the damper position of the HVAC system real-time by comparing the levels of carbon dioxide, fine dust, and temperature and humidity inside and outside the building. Simulation results show that the new HVAC system saves 32% in annual energy consumption compared to the previous system and maintains the concentration of fine dust and carbon dioxide within the range of conditions that allow occupants to comfortably carry out activities.

제로에너지건축물(ZEB/H) 설비시스템 기술로드맵 수립을 위한 선행연구 분석: 최근 10년 해외연구사례

장승민,장아민,도성록,조진균,김철 대한설비공학회 2023 설비공학 논문집 Vol.35 No.9

The concept and technology of zero energy building/house (ZEB/H) has been developed as an effective solution to reduce greenhouse gas (GHG) emissions and energy consumption in buildings. This paper analyzes ZEB/H research done for the past decade to provide insights and accelerate its implementation in the active system sector. It investigates key research areas in heating, ventilation, air conditioning and refrigeration (HVAC&R) systems, identifies enabling technologies and proposes a technical direction and roadmap for achieving ZEB/H. The study focuses on energy-efficient heating/cooling, ventilation, renewable energy, and design strategy of HVAC&R systems. The analysis also highlights the significance of domestic hot water (DHW) systems in ZEB/H implementation, covering topics such as DHW profiles, demand forecasting, control, and system design. It emphasizes that residential and nonresidential buildings require different research approaches, with nonresidential focusing on HVAC&R and residential emphasizing domestic hot water and ventilation. The future development of ZEB/H active systems should incorporate digital technology in HVAC&R, integrate renewable energy and optimal operation technology, establish regional heat networks and integrate building and active systems. 본 논문은 ZEB/H에 대한 최근 10년간 연구를 분석하여 기술적 통찰력을 제공하고, 설비 분야에서 ZEB/H 구현을 가속화하기 위한 목적으로 연구를 수행하였다. 이를 위해서 설비시스템의 주요 연구 분야를 조사하고, 요소 기술을 파악하여 ZEB/H 달성을 위한 기술 방향과 로드맵을 제시하는 것을 목표로 한다. 연구 내용은 다음과 같이 요약이 가능하다. ∙HVAC&R 시스템은 건물의 에너지 소비를 줄이고 에너지 효율성을 향상시키는 역할을 한다. HVAC&R 시스템의 냉난방, 환기, 신재생에너지 및 최적화 설계를 중심으로 대해 조사되었다. ∙DHW(급탕) 시스템은 ZEH 구현에 중요한 역할을 하며, 급탕 프로파일, 급탕량 예측 및 제어, 최적화 시스템 설계 등을 연구의 대상으로 상세 분석을 수행하였다. ∙분석 결과, 주거용 건물과 비주거용 건물은 HVAC&R 및 급탕 시스템에 대한 연구 접근 방식이 다르다. 비주거용 ZEB은 HVAC&R, 주거용 ZEH는 급탕 및 환기에 중점을 두고 연구가 진행되었다. ∙ZEB/H 설비시스템의 고도화를 위한 기술개발 방향은 HVAC&R에 디지털 기술 접목, 신재생에너지와 최적운전 기술 결합, 지역단위 열 네트워크 구축, 건축과 설비시스템 통합 등으로 확장할 수 있다. ZEB/H는 오랜 기간 준비해 온 중요한 국가 프로젝트이다. 기술적 균형 측면에서 이제는 설비시스템의 고도화를 통하여 건축시스템과 융합된 실현 가능한 ZEB/H를 구현하는 것이 현시점에서 최선의 대응일 것으로 판단된다. 본 논문의 내용이 향후 설비기술의 로드맵을 설정하는 기초자료로 활용 가능할 것으로 사료된다.

Adaptive Fuzzy Output Feedback Control based on Observer for Nonlinear Heating, Ventilating and Air Conditioning System

Jaeho Baek,Eun-ju Hwang,Euntai Kim,Mignon Park 한국지능시스템학회 2009 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.9 No.2

A Heating, Ventilating and Air Conditioning (HVAC) system is a nonlinear multi-input multi-output (MIMO) system. This system is very difficult to control the temperature and the humidity ratio of a thermal space because of complex nonlinear characteristics. This paper proposes an adaptive fuzzy output feedback control based on observer for the nonlinear HVAC system. The nonlinear HVAC system is linearized through dynamic extension. State observers are designed for estimating state variables of the HVAC system. Fuzzy systems are employed to approximate uncertain nonlinear functions of the HVAC system with unavailable state variables. The obtained controller compares with an adaptive feedback controller. Simulation is given to demonstrate the effectiveness of our proposed adaptive fuzzy method.

선박용 통합 HVAC 소음해석 프로그램 개발

한주범(Ju-Bum Han),홍석윤(Suk-Yoon Hong),송지훈(Jee-Hun Song),김노성(Nho-Seong Kim),천승현(Seung-Hyun Chun) 한국소음진동공학회 2011 한국소음진동공학회 학술대회논문집 Vol.2011 No.4

The Main design parameters of ship HVAC systems are pressure drop and noise analysis of ducts. The Noise prediction for HVAC(Heating, Ventilating and Air Conditioning) systems are normally performed by empirical method suggested by NEBB(National Environmental Balancing Bureau, 1994), but NEBB’s method is not suitable for the ship HVAC systems. In this paper, numerical analysis methods are used to develop a noise prediction method for the ship HVAC systems, especially for large ducts. To develop regression formula of attenuation of sound pressure level in large duct, Boundary Element Method(BEM) is used. Using dynamic loss coefficient which is suggested by ASHRAE fitting data base and numerical methods of HVAC noise analysis, integrated HVAC noise analysis of Program is developed. The developed program can present pressure drop and noise analysis of the ship HVAC systems. To verify the accuracy and convenience of the developed program, prediction of HVAC system for Semi-Submersible Drilling RIG is carried out and the results are compared with measurement of noise level during sea trial.

초고층, 대규모 건물의 에너지 절약적 공조방식 선정을 위한 설계접근 방안에 대한 연구

조진균(Cho Jin-Kyun),정차수(Jeong Cha-Su),김병선(Kim Byung-Seon) 대한건축학회 2008 대한건축학회논문집 Vol.24 No.6

More than 60% of people all over the world are living in urban areas, and the people and buildings keep spending energy, and it makes excessive problems of global energy system. Currently, lots of attention is being paid for how to design HVAC(heating ventilating air conditioning) system in large-scale and high-rise buildings. Increasing awareness of energy use is main point of this research. HVAC systems' energy characteristics are not clearly identified and understood, so the optimal design of HVAC system is very important. Despite the fact that cold air distribution system, displacement air conditioning system, UFAD(under floor air distribution) system, cooling/heating radiation system, chilled beam system and DOAS(dedicated outdoor air system) have many energy conservational benefits and are being applied in the field in increasing numbers, there is need for fundamental understandings of several energy consumption factor of these HVAC systems. This study investigates the energy parameters of HVAC design that are system input energy, water/air moving equipments(pumps/fans) energy and outdoor air conditioning energy for IAQ. The purpose of this study is to provide the basic data for energy conservation strategies and it is a main target in the development of HVAC system selection/design guideline.

Development and Application of Engineering Integration Program for HVAC System of Offshore Facility

Sung-Ju Lee,Yong-hwan Park,Hee-sung Lee 대한설비공학회 2022 대한설비공학회 학술발표대회논문집 Vol.2022 No.6

In case of the HVAC system of offshore facilities, the system is very large and complex because it is densely arranged with other equipment systems in a limited space. In general, engineering for HVAC systems uses a simple method for time and cost efficiency. However, the simple method is not suitable for such a complex system like those of offshore facility. It is because of large error occurs in the simplification process. In addition, the HVAC system is connected each other so that a change in one design variable affects the entire system. Therefore, as the system becomes more complex, there is a need for an engineering platform that can integrate and control engineering data for all design stages. In order to overcome the limitations of currently applied method and to perform efficient and accurate analysis for complex systems, new engineering integration program for HVAC system was developed and the effect was verified by applying the program in actual project.

Design of Supervisory Model Predictive Control for Building HVAC System with Time-Varying Coefficient of Performance

Chanthawit Anuntasethakul,Kantapong Leungrungwason,David Banjerdpongchai 제어로봇시스템학회 2021 제어로봇시스템학회 국제학술대회 논문집 Vol.2021 No.10

This paper presents a design of supervisory model predictive control (SMPC) for a building heating-ventilation-air-conditioning (HVAC) system. The control objectives are to minimize the total operating cost (TOC) and the thermal comfort cost (TCC). According to practical realization, a coefficient of performance (COP) is a time-varying parameter of HVAC system and depends on environment conditions. Therefore, we employ an artificial neural network (ANN) with k-means clustering to predict the COP. We design the SMPC to determine the optimal set-point temperature for the HVAC system which serves our control objectives. We utilize the predicted mean vote (PMV) to handle thermal comfort of occupants and to indicate an acceptable bound of the optimal set-point temperature. We formulate the SMPC with the predicted COP integration as two quadratic programs. The first quadratic program is a supervisory control problem for optimal set-point searching problem and the other is an MPC problem for optimal control input searching problem. Our results reveal that the root-mean-square error (RMSE) of the predicted COP is reduced by 34% using the clustered-ANN. When the SMPC is applied to the time-varying HVAC system, the TOC decreases by 14.53% compared to that of the nominal operation. Moreover, the maximum electrical power of the HVAC system is reduced by 15.66% resulting from smoothly shaved electrical power profile.

Adaptive Fuzzy Output Feedback Control based on Observer for Nonlinear Heating, Ventilating and Air Conditioning System

백재호,황은주,김은태,박민용 한국지능시스템학회 2009 INTERNATIONAL JOURNAL of FUZZY LOGIC and INTELLIGE Vol.9 No.2

A Heating, Ventilating and Air Conditioning (HVAC) system is a nonlinear multi-input multi-output (MIMO) system. This system is very difficult to control the temperature and the humidity ratio of a thermal space because of complex nonlinear characteristics. This paper proposes an adaptive fuzzy output feedback control based on observer for the nonlinear HVAC system. The nonlinear HVAC system is linearized through dynamic extension. State observers are designed for estimating state variables of the HVAC system. Fuzzy systems are employed to approximate uncertain nonlinear functions of the HVAC system with unavailable state variables. The obtained controller compares with an adaptive feedback controller. Simulation is given to demonstrate the effectiveness of our proposed adaptive fuzzy method.

건물의 냉, 난방 부하비율과 HVAC&R 시스템 1차 에너지 소비량의 상관관계분석 및 합리적 설계방안 연구

조진균(Jinkyun Cho),김진호(Jinho Kim),이성재(Suengjae Lee),강호석(Hosuk Kang) 대한설비공학회 2015 설비공학 논문집 Vol.27 No.3

HVAC&R systems account for more than 50% of the energy consumption of buildings. The purpose of this study is to propose an optimal design method for the HVAC&R system and to examine the possibility for the energy conservation of a selected system. The energy demand for cooling and heating is determined by using TRNSYS and HEET. By an interaction between total system efficiency and cooling-to-heating load ratio, the optimal HVAC&R systems will be decided. The results showed that this proposed method is significantly capable of determining optimal system and building design for saving energy.