Model calibration for building energy efficiency simulation

International Nuclear Information System (INIS)

Mustafaraj, Giorgio; Marini, Dashamir; Costa, Andrea; Keane, Marcus

2014-01-01

Highlights: • Developing a 3D model relating to building architecture, occupancy and HVAC operation. • Two calibration stages developed, final model providing accurate results. • Using an onsite weather station for generating the weather data file in EnergyPlus. • Predicting thermal behaviour of underfloor heating, heat pump and natural ventilation. • Monthly energy saving opportunities related to heat pump of 20–27% was identified. - Abstract: This research work deals with an Environmental Research Institute (ERI) building where an underfloor heating system and natural ventilation are the main systems used to maintain comfort condition throughout 80% of the building areas. Firstly, this work involved developing a 3D model relating to building architecture, occupancy and HVAC operation. Secondly, the calibration methodology, which consists of two levels, was then applied in order to insure accuracy and reduce the likelihood of errors. To further improve the accuracy of calibration a historical weather data file related to year 2011, was created from the on-site local weather station of ERI building. After applying the second level of calibration process, the values of Mean bias Error (MBE) and Cumulative Variation of Root Mean Squared Error (CV(RMSE)) on hourly based analysis for heat pump electricity consumption varied within the following ranges: (MBE) hourly from −5.6% to 7.5% and CV(RMSE) hourly from 7.3% to 25.1%. Finally, the building was simulated with EnergyPlus to identify further possibilities of energy savings supplied by a water to water heat pump to underfloor heating system. It found that electricity consumption savings from the heat pump can vary between 20% and 27% on monthly bases

Building Performance Simulation for Sustainable Energy Use in Buildings

NARCIS (Netherlands)

Hensen, J.L.M.

2010-01-01

This paper aims to provide a general view of the background and current state of building performance simulation, which has the potential to deliver, directly or indirectly, substantial benefits to building stakeholders and to the environment. However the building simulation community faces many

A SOFTWARE TOOL TO COMPARE MEASURED AND SIMULATED BUILDING ENERGY PERFORMANCE DATA

Energy Technology Data Exchange (ETDEWEB)

Maile, Tobias; Bazjanac, Vladimir; O' Donnell, James; Garr, Matthew

2011-11-01

Building energy performance is often inadequate when compared to design goals. To link design goals to actual operation one can compare measured with simulated energy performance data. Our previously developed comparison approach is the Energy Performance Comparison Methodology (EPCM), which enables the identification of performance problems based on a comparison of measured and simulated performance data. In context of this method, we developed a software tool that provides graphing and data processing capabilities of the two performance data sets. The software tool called SEE IT (Stanford Energy Efficiency Information Tool) eliminates the need for manual generation of data plots and data reformatting. SEE IT makes the generation of time series, scatter and carpet plots independent of the source of data (measured or simulated) and provides a valuable tool for comparing measurements with simulation results. SEE IT also allows assigning data points on a predefined building object hierarchy and supports different versions of simulated performance data. This paper briefly introduces the EPCM, describes the SEE IT tool and illustrates its use in the context of a building case study.

Low-energy office buildings using existing technology. Simulations with low internal heat gains

Energy Technology Data Exchange (ETDEWEB)

Flodberg, Kajsa; Blomsterberg, Aake; Dubois, Marie-Claude [Lund Univ. (Sweden). Div. of Energy and Building Design

2012-11-01

Although low-energy and nearly zero-energy residential houses have been built in Sweden in the past decade, there are very few examples of low-energy office buildings. This paper investigates the design features affecting energy use in office buildings and suggests the optimal low-energy design from a Swedish perspective. Dynamic simulations have been carried out with IDA ICE 4 on a typical narrow office building with perimeter cell rooms. The results from the parametric study reveal that the most important design features for energy saving are demand-controlled ventilation as well as limited glazing on the facade. Further energy-saving features are efficient lighting and office equipment which strongly reduce user-related electricity and cooling energy. Together, the simulation results suggest that about 48% energy can be saved compared to a new office building built according to the Swedish building code. Thus, it is possible, using a combination of simple and well-known building technologies and configurations, to have very low energy use in new office buildings. If renewable energy sources, such as solar energy and wind power, are added, there is a potential for the annual energy production to exceed the annual energy consumption and a net zero-energy building can be reached. One aspect of the results concerns user-related electricity, which becomes a major energy post in very low-energy offices and which is rarely regulated in building codes today. This results not only in high electricity use, but also in large internal heat gains and unnecessary high cooling loads given the high latitude and cold climate. (orig.)

Influence of simulation assumptions and input parameters on energy balance calculations of residential buildings

International Nuclear Information System (INIS)

Dodoo, Ambrose; Tettey, Uniben Yao Ayikoe; Gustavsson, Leif

2017-01-01

In this study, we modelled the influence of different simulation assumptions on energy balances of two variants of a residential building, comprising the building in its existing state and with energy-efficient improvements. We explored how selected parameter combinations and variations affect the energy balances of the building configurations. The selected parameters encompass outdoor microclimate, building thermal envelope and household electrical equipment including technical installations. Our modelling takes into account hourly as well as seasonal profiles of different internal heat gains. The results suggest that the impact of parameter interactions on calculated space heating of buildings is somewhat small and relatively more noticeable for an energy-efficient building in contrast to a conventional building. We find that the influence of parameters combinations is more apparent as more individual parameters are varied. The simulations show that a building's calculated space heating demand is significantly influenced by how heat gains from electrical equipment are modelled. For the analyzed building versions, calculated final energy for space heating differs by 9–14 kWh/m"2 depending on the assumed energy efficiency level for electrical equipment. The influence of electrical equipment on calculated final space heating is proportionally more significant for an energy-efficient building compared to a conventional building. This study shows the influence of different simulation assumptions and parameter combinations when varied simultaneously. - Highlights: • Energy balances are modelled for conventional and efficient variants of a building. • Influence of assumptions and parameter combinations and variations are explored. • Parameter interactions influence is apparent as more single parameters are varied. • Calculated space heating demand is notably affected by how heat gains are modelled.

Using the building energy simulation test (BESTEST) to evaluate CHENATH, the Nationwide House Energy Rating Scheme Simulation Engine

Energy Technology Data Exchange (ETDEWEB)

Delsante, A.E. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), Highett, VIC (Australia). Div. of Building Construction and Engineering

1995-12-31

The Nationwide House Energy Rating Scheme (NatHERS) uses a simulation program as its reference tool to evaluate the energy demand of buildings. The Commonwealth Scientific Industrial Research Organisation (CSIRO) developed software called CHENATH, is a significantly enhanced version of the CHEETAH simulation program. As part of the NatHERS development process, it was considered important to subject CHENATH to further testing. Two separate evaluation projects were undertaken. This paper describes one of these projects. CHENATH was compared with a reference set of eight internationally recognized simulation programs using the BESTEST methodology. Annual heating and cooling energy requirements were compared for a specified set of variations on a simple double-glazed building. Annual incident and transmitted solar radiation was also compared, for which CHENATH agreed very well with the reference set. It also agreed well for heating energy, but tended to over-predict cooling energy. This is largely because it controls an environmental temperature rather than the required air temperature. For the same reason CHENATH over-predicted heating and cooling demands. No major discrepancies were found that would suggest bugs in the program. (author). 4 tabs., 10 figs., 4 refs.

Methodology for Validating Building Energy Analysis Simulations

Energy Technology Data Exchange (ETDEWEB)

Judkoff, R.; Wortman, D.; O' Doherty, B.; Burch, J.

2008-04-01

The objective of this report was to develop a validation methodology for building energy analysis simulations, collect high-quality, unambiguous empirical data for validation, and apply the validation methodology to the DOE-2.1, BLAST-2MRT, BLAST-3.0, DEROB-3, DEROB-4, and SUNCAT 2.4 computer programs. This report covers background information, literature survey, validation methodology, comparative studies, analytical verification, empirical validation, comparative evaluation of codes, and conclusions.

Thermal dynamic simulation of wall for building energy efficiency under varied climate environment

Science.gov (United States)

Wang, Xuejin; Zhang, Yujin; Hong, Jing

2017-08-01

Aiming at different kind of walls in five cities of different zoning for thermal design, using thermal instantaneous response factors method, the author develops software to calculation air conditioning cooling load temperature, thermal response factors, and periodic response factors. On the basis of the data, the author gives the net work analysis about the influence of dynamic thermal of wall on air-conditioning load and thermal environment in building of different zoning for thermal design regional, and put forward the strategy how to design thermal insulation and heat preservation wall base on dynamic thermal characteristic of wall under different zoning for thermal design regional. And then provide the theory basis and the technical references for the further study on the heat preservation with the insulation are in the service of energy saving wall design. All-year thermal dynamic load simulating and energy consumption analysis for new energy-saving building is very important in building environment. This software will provide the referable scientific foundation for all-year new thermal dynamic load simulation, energy consumption analysis, building environment systems control, carrying through farther research on thermal particularity and general particularity evaluation for new energy -saving walls building. Based on which, we will not only expediently design system of building energy, but also analyze building energy consumption and carry through scientific energy management. The study will provide the referable scientific foundation for carrying through farther research on thermal particularity and general particularity evaluation for new energy saving walls building.

Thermal comfort in residential buildings: Comfort values and scales for building energy simulation

NARCIS (Netherlands)

Peeters, L.F.R.; Dear, de R.; Hensen, J.L.M.; D'Haeseleer, W.

2009-01-01

Building Energy Simulation (BES) programmes often use conventional thermal comfort theories to make decisions, whilst recent research in the field of thermal comfort clearly shows that important effects are not incorporated. The conventional theories of thermal comfort were set up based on steady

MALAYSIAN WEATHER DATA (TRY) FOR ENERGY SIMULATIONS IN BUILDINGS

DEFF Research Database (Denmark)

Reimann, Gregers Peter

2001-01-01

Detailed energy simulations for buildings in Malaysia have become possible after the recent construction of a Malaysian TRY (Test Reference Year) based on 21 years of hourly weather data from Subang Meteorological Station. The climatic parameters contained in the TRY are dry bulb temperature, wet...

Modeling and simulation of the energy use in an occupied residential building in cold climate

International Nuclear Information System (INIS)

Olofsson, Thomas; Mahlia, T.M.I.

2012-01-01

Highlights: ► An overview of the energy-characteristics based on illustrations in graphical figures. ► Figures to support identification and validation energy refurbishment measures. ► Emphasizing energy efficiency measures in early stage of building design. -- Abstract: In order to reduce the energy use in the building sector there is a demand for tools that can identify significant building energy performance parameters. In the work introduced in this paper presents a methodology, based on a simulation module and graphical figures, for interactive investigations of the building energy performance. The building energy use simulation program is called TEKLA and is using EN832 with an improved procedure in calculating the heat loss through the floor and the solar heat gain. The graphical figures are simple and are illustrating the savings based on retrofit measures and climate conditions. The accuracy of the TEKLA simulation was investigated on a typical single-family building in Sweden for a period of time in a space heating demand of relatively cold and mild climate. The model was found applicable for relative investigations. Further, the methodology was applied on a typical single family reference building. The climate data from three locations in Sweden were collected and a set of relevant measures were studied. The investigated examples illustrate how decisions in the early stages of the building design process can have decisive importance on the final building energy performance.

Advancement of DOE's EnergyPlus Building Energy Simulation Payment

Energy Technology Data Exchange (ETDEWEB)

Gu, Lixing [Florida Solar Energy Center, Cocoa, FL (United States); Shirey, Don [Florida Solar Energy Center, Cocoa, FL (United States); Raustad, Richard [Florida Solar Energy Center, Cocoa, FL (United States); Nigusse, Bereket [Florida Solar Energy Center, Cocoa, FL (United States); Sharma, Chandan [Florida Solar Energy Center, Cocoa, FL (United States); Lawrie, Linda [DHL Consulting, Bonn (Germany); Strand, Rick [Univ. of Illinois, Champaign, IL (United States); Pedersen, Curt [COPA, Panama City (Panama); Fisher, Dan [Oklahoma State Univ., Stillwater, OK (United States); Lee, Edwin [Oklahoma State Univ., Stillwater, OK (United States); Witte, Mike [GARD Analytics, Arlington Heights, IL (United States); Glazer, Jason [GARD Analytics, Arlington Heights, IL (United States); Barnaby, Chip [Wrightsoft, Lexington, MA (United States)

2011-09-30

EnergyPlus{sup TM} is a new generation computer software analysis tool that has been developed, tested, and commercialized to support DOE's Building Technologies (BT) Program in terms of whole-building, component, and systems R&D (http://www.energyplus.gov). It is also being used to support evaluation and decision making of zero energy building (ZEB) energy efficiency and supply technologies during new building design and existing building retrofits. The 5-year project was managed by the National Energy Technology Laboratory and was divided into 5 budget period between 2006 and 2011. During the project period, 11 versions of EnergyPlus were released. This report summarizes work performed by an EnergyPlus development team led by the University of Central Florida's Florida Solar Energy Center (UCF/FSEC). The team members consist of DHL Consulting, C. O. Pedersen Associates, University of Illinois at Urbana-Champaign, Oklahoma State University, GARD Analytics, Inc., and WrightSoft Corporation. The project tasks involved new feature development, testing and validation, user support and training, and general EnergyPlus support. The team developed 146 new features during the 5-year period to advance the EnergyPlus capabilities. Annual contributions of new features are 7 in budget period 1, 19 in period 2, 36 in period 3, 41 in period 4, and 43 in period 5, respectively. The testing and validation task focused on running test suite and publishing report, developing new IEA test suite cases, testing and validating new source code, addressing change requests, and creating and testing installation package. The user support and training task provided support for users and interface developers, and organized and taught workshops. The general support task involved upgrading StarTeam (team sharing) software and updating existing utility software. The project met the DOE objectives and completed all tasks successfully. Although the EnergyPlus software was enhanced

Effective Energy Simulation and Optimal Design of Side-lit Buildings with Venetian Blinds

Science.gov (United States)

Cheng, Tian

Venetian blinds are popularly used in buildings to control the amount of incoming daylight for improving visual comfort and reducing heat gains in air-conditioning systems. Studies have shown that the proper design and operation of window systems could result in significant energy savings in both lighting and cooling. However, there is no convenient computer tool that allows effective and efficient optimization of the envelope of side-lit buildings with blinds now. Three computer tools, Adeline, DOE2 and EnergyPlus widely used for the above-mentioned purpose have been experimentally examined in this study. Results indicate that the two former tools give unacceptable accuracy due to unrealistic assumptions adopted while the last one may generate large errors in certain conditions. Moreover, current computer tools have to conduct hourly energy simulations, which are not necessary for life-cycle energy analysis and optimal design, to provide annual cooling loads. This is not computationally efficient, particularly not suitable for optimal designing a building at initial stage because the impacts of many design variations and optional features have to be evaluated. A methodology is therefore developed for efficient and effective thermal and daylighting simulations and optimal design of buildings with blinds. Based on geometric optics and radiosity method, a mathematical model is developed to reasonably simulate the daylighting behaviors of venetian blinds. Indoor illuminance at any reference point can be directly and efficiently computed. They have been validated with both experiments and simulations with Radiance. Validation results show that indoor illuminances computed by the new models agree well with the measured data, and the accuracy provided by them is equivalent to that of Radiance. The computational efficiency of the new models is much higher than that of Radiance as well as EnergyPlus. Two new methods are developed for the thermal simulation of buildings. A

Simulation of energy- efficient building prototype using different insulating materials

Science.gov (United States)

Ouhaibi, Salma; Belouaggadia, Naoual; Lbibb, Rachid; Ezzine, Mohammed

2018-05-01

The objective of this work is to analyze the energetic efficiency of an individual building including an area of 130 m2 multi-zone, located in the region of FEZ which is characterized by a very hot and dry climate in summer and a quite cold one in winter, by incorporating insulating materials. This study was performed using TRNSYS V16 simulation software during a typical year of the FEZ region. Our simulation consists in developing a comparative study of two types of polystyrene and silica-aerogel insulation materials, in order to determine the best thermal performance. The results show that the thermal insulation of the building envelope is among the most effective solutions that give a significant reduction in energy requirements. Similarly, the use of silica-aerogels gives a good thermal performance, and therefore a good energy gain.

Thermal comfort in residential buildings: Comfort values and scales for building energy simulation

Energy Technology Data Exchange (ETDEWEB)

Peeters, Leen; D' haeseleer, William [Division of Applied Mechanics and Energy Conversion, University of Leuven (K.U.Leuven), Celestijnenlaan 300 A, B-3001 Leuven (Belgium); Dear, Richard de [Division of Environmental and Life Sciences, Macquarie University, Sydney (Australia); Hensen, Jan [Faculty of Architecture, Building and Planning, Technische Universiteit Eindhoven, Vertigo 6.18, P.O. Box 513, 5600 MB Eindhoven (Netherlands)

2009-05-15

Building Energy Simulation (BES) programmes often use conventional thermal comfort theories to make decisions, whilst recent research in the field of thermal comfort clearly shows that important effects are not incorporated. The conventional theories of thermal comfort were set up based on steady state laboratory experiments. This, however, is not representing the real situation in buildings, especially not when focusing on residential buildings. Therefore, in present analysis, recent reviews and adaptations are considered to extract acceptable temperature ranges and comfort scales. They will be defined in an algorithm, easily implementable in any BES code. The focus is on comfortable temperature levels in the room, more than on the detailed temperature distribution within that room. (author)

Co-Simulation of Building Energy and Control Systems with the Building Controls Virtual Test Bed

Energy Technology Data Exchange (ETDEWEB)

Wetter, Michael

2010-08-22

This article describes the implementation of the Building Controls Virtual Test Bed (BCVTB). The BCVTB is a software environment that allows connecting different simulation programs to exchange data during the time integration, and that allows conducting hardware in the loop simulation. The software architecture is a modular design based on Ptolemy II, a software environment for design and analysis of heterogeneous systems. Ptolemy II provides a graphical model building environment, synchronizes the exchanged data and visualizes the system evolution during run-time. The BCVTB provides additions to Ptolemy II that allow the run-time coupling of different simulation programs for data exchange, including EnergyPlus, MATLAB, Simulink and the Modelica modelling and simulation environment Dymola. The additions also allow executing system commands, such as a script that executes a Radiance simulation. In this article, the software architecture is presented and the mathematical model used to implement the co-simulation is discussed. The simulation program interface that the BCVTB provides is explained. The article concludes by presenting applications in which different state of the art simulation programs are linked for run-time data exchange. This link allows the use of the simulation program that is best suited for the particular problem to model building heat transfer, HVAC system dynamics and control algorithms, and to compute a solution to the coupled problem using co-simulation.

Energy simulation in building design

NARCIS (Netherlands)

Hensen, J.L.M.

1992-01-01

Design decision support related to building energy consumption and / or indoor climate, should be based on an integral approach of environment, building, heating, ventilating and airconditioning (HVAC) system and occupants. The tools to achieve this are now available in the form of computer

Simulation of building energy and indoor environmental quality - some weather data issues

NARCIS (Netherlands)

Hensen, J.L.M.

1999-01-01

After elaborating that a building is a rather complicated dynamic system where many of the governing energy and mass transfer relationships are highly non-linear, this paper focuses on weather data as needed for computer simulation of buildings. The paper does not aim for completeness but rather to

Solar energy in buildings solved by building information modeling

Science.gov (United States)

Chudikova, B.; Faltejsek, M.

2018-03-01

Building lead us to use renewable energy sources for all types of buildings. The use of solar energy is the alternatives that can be applied in a good ratio of space, price, and resultant benefits. Building Information Modelling is a modern and effective way of dealing with buildings with regard to all aspects of the life cycle. The basis is careful planning and simulation in the pre-investment phase, where it is possible to determine the effective result and influence the lifetime of the building and the cost of its operation. By simulating, analysing and insert a building model into its future environment where climate conditions and surrounding buildings play a role, it is possible to predict the usability of the solar energy and establish an ideal model. Solar systems also very affect the internal layout of buildings. Pre-investment phase analysis, with a view to future aspects, will ensure that the resulting building will be both low-energy and environmentally friendly.

Stochastic Modeling of Overtime Occupancy and Its Application in Building Energy Simulation and Calibration

Energy Technology Data Exchange (ETDEWEB)

Sun, Kaiyu; Yan, Da; Hong, Tianzhen; Guo, Siyue

2014-02-28

Overtime is a common phenomenon around the world. Overtime drives both internal heat gains from occupants, lighting and plug-loads, and HVAC operation during overtime periods. Overtime leads to longer occupancy hours and extended operation of building services systems beyond normal working hours, thus overtime impacts total building energy use. Current literature lacks methods to model overtime occupancy because overtime is stochastic in nature and varies by individual occupants and by time. To address this gap in the literature, this study aims to develop a new stochastic model based on the statistical analysis of measured overtime occupancy data from an office building. A binomial distribution is used to represent the total number of occupants working overtime, while an exponential distribution is used to represent the duration of overtime periods. The overtime model is used to generate overtime occupancy schedules as an input to the energy model of a second office building. The measured and simulated cooling energy use during the overtime period is compared in order to validate the overtime model. A hybrid approach to energy model calibration is proposed and tested, which combines ASHRAE Guideline 14 for the calibration of the energy model during normal working hours, and a proposed KS test for the calibration of the energy model during overtime. The developed stochastic overtime model and the hybrid calibration approach can be used in building energy simulations to improve the accuracy of results, and better understand the characteristics of overtime in office buildings.

Relative significance of heat transfer processes to quantify tradeoffs between complexity and accuracy of energy simulations with a building energy use patterns classification

Science.gov (United States)

Heidarinejad, Mohammad

This dissertation develops rapid and accurate building energy simulations based on a building classification that identifies and focuses modeling efforts on most significant heat transfer processes. The building classification identifies energy use patterns and their contributing parameters for a portfolio of buildings. The dissertation hypothesis is "Building classification can provide minimal required inputs for rapid and accurate energy simulations for a large number of buildings". The critical literature review indicated there is lack of studies to (1) Consider synoptic point of view rather than the case study approach, (2) Analyze influence of different granularities of energy use, (3) Identify key variables based on the heat transfer processes, and (4) Automate the procedure to quantify model complexity with accuracy. Therefore, three dissertation objectives are designed to test out the dissertation hypothesis: (1) Develop different classes of buildings based on their energy use patterns, (2) Develop different building energy simulation approaches for the identified classes of buildings to quantify tradeoffs between model accuracy and complexity, (3) Demonstrate building simulation approaches for case studies. Penn State's and Harvard's campus buildings as well as high performance LEED NC office buildings are test beds for this study to develop different classes of buildings. The campus buildings include detailed chilled water, electricity, and steam data, enabling to classify buildings into externally-load, internally-load, or mixed-load dominated. The energy use of the internally-load buildings is primarily a function of the internal loads and their schedules. Externally-load dominated buildings tend to have an energy use pattern that is a function of building construction materials and outdoor weather conditions. However, most of the commercial medium-sized office buildings have a mixed-load pattern, meaning the HVAC system and operation schedule dictate

Empirical Validation of Building Simulation Software

DEFF Research Database (Denmark)

Kalyanova, Olena; Heiselberg, Per

The work described in this report is the result of a collaborative effort of members of the International Energy Agency (IEA), Task 34/43: Testing and validation of building energy simulation tools experts group.......The work described in this report is the result of a collaborative effort of members of the International Energy Agency (IEA), Task 34/43: Testing and validation of building energy simulation tools experts group....

ExRET-Opt: An automated exergy/exergoeconomic simulation framework for building energy retrofit analysis and design optimisation

International Nuclear Information System (INIS)

García Kerdan, Iván; Raslan, Rokia; Ruyssevelt, Paul; Morillón Gálvez, David

2017-01-01

Highlights: • Development of a building retrofit-oriented exergoeconomic-based optimisation tool. • A new exergoeconomic cost-benefit indicator is developed for design comparison. • Thermodynamic and thermal comfort variables used as constraints and/or objectives. • Irreversibilities and exergetic cost for end-use processes are substantially reduced. • Robust methodology that should be pursued in everyday building retrofit practice. - Abstract: Energy simulation tools have a major role in the assessment of building energy retrofit (BER) measures. Exergoeconomic analysis and optimisation is a common practice in sectors such as the power generation and chemical processes, aiding engineers to obtain more energy-efficient and cost-effective energy systems designs. ExRET-Opt, a retrofit-oriented modular-based dynamic simulation framework has been developed by embedding a comprehensive exergy/exergoeconomic calculation method into a typical open-source building energy simulation tool (EnergyPlus). The aim of this paper is to show the decomposition of ExRET-Opt by presenting modules, submodules and subroutines used for the framework’s development as well as verify the outputs with existing research data. In addition, the possibility to perform multi-objective optimisation analysis based on genetic-algorithms combined with multi-criteria decision making methods was included within the simulation framework. This addition could potentiate BER design teams to perform quick exergy/exergoeconomic optimisation, in order to find opportunities for thermodynamic improvements along the building’s active and passive energy systems. The enhanced simulation framework is tested using a primary school building as a case study. Results demonstrate that the proposed simulation framework provide users with thermodynamic efficient and cost-effective designs, even under tight thermodynamic and economic constraints, suggesting its use in everyday BER practice.

Building energy simulation using multi-years and typical meteorological years in different climates

International Nuclear Information System (INIS)

Yang Liu; Lam, Joseph C.; Liu Jiaping; Tsang, C.L.

2008-01-01

Detailed hourly energy simulation was conducted for office buildings in the five major climate zones - severe cold, cold, hot summer and cold winter, mild and hot summer and warm winter - in China using multi-year (1971-2000) weather databases as well as typical meteorological years (TMY). The primary aim was to compare the energy simulation results from the TMY with those from individual years and their long term means. A total of 154 simulation runs were performed. Building heating and cooling loads, their components and energy use for heating, ventilation and air-conditioning were analysed. Predicted monthly load and energy consumption profiles from the TMY tended to follow the long term mean quite closely. Mean bias errors ranged from -4.3% in Guangzhou to 0% in Beijing and root-mean-square errors from 3% in Harbin to 5.4% in Guangzhou. These percentages were not always the smallest compared with the 30 individual years, however, they are at the lower end of the percentage error ranges. This paper presents the work and its findings

Validation studies of the DOE-2 Building Energy Simulation Program. Final Report

Energy Technology Data Exchange (ETDEWEB)

Sullivan, R.; Winkelmann, F.

1998-06-01

This report documents many of the validation studies (Table 1) of the DOE-2 building energy analysis simulation program that have taken place since 1981. Results for several versions of the program are presented with the most recent study conducted in 1996 on version DOE-2.1E and the most distant study conducted in 1981 on version DOE-1.3. This work is part of an effort related to continued development of DOE-2, particularly in its use as a simulation engine for new specialized versions of the program such as the recently released RESFEN 3.1. RESFEN 3.1 is a program specifically dealing with analyzing the energy performance of windows in residential buildings. The intent in providing the results of these validation studies is to give potential users of the program a high degree of confidence in the calculated results. Validation studies in which calculated simulation data is compared to measured data have been conducted throughout the development of the DOE-2 program. Discrepancies discovered during the course of such work has resulted in improvements in the simulation algorithms. Table 2 provides a listing of additions and modifications that have been made to various versions of the program since version DOE-2.1A. One of the most significant recent changes in the program occurred with version DOE-2.1E. An improved algorithm for calculating the outside surface film coefficient was implemented. In addition, integration of the WINDOW 4 program was accomplished resulting in improved ability in analyzing window energy performance. Validation and verification of a program as sophisticated as DOE-2 must necessarily be limited because of the approximations inherent in the program. For example, the most accurate model of the heat transfer processes in a building would include a three-dimensional analysis. To justify such detailed algorithmic procedures would correspondingly require detailed information describing the building and/or HVAC system and energy plant parameters

Analysis and Optimization of Building Energy Consumption

Science.gov (United States)

Chuah, Jun Wei

Energy is one of the most important resources required by modern human society. In 2010, energy expenditures represented 10% of global gross domestic product (GDP). By 2035, global energy consumption is expected to increase by more than 50% from current levels. The increased pace of global energy consumption leads to significant environmental and socioeconomic issues: (i) carbon emissions, from the burning of fossil fuels for energy, contribute to global warming, and (ii) increased energy expenditures lead to reduced standard of living. Efficient use of energy, through energy conservation measures, is an important step toward mitigating these effects. Residential and commercial buildings represent a prime target for energy conservation, comprising 21% of global energy consumption and 40% of the total energy consumption in the United States. This thesis describes techniques for the analysis and optimization of building energy consumption. The thesis focuses on building retrofits and building energy simulation as key areas in building energy optimization and analysis. The thesis first discusses and evaluates building-level renewable energy generation as a solution toward building energy optimization. The thesis next describes a novel heating system, called localized heating. Under localized heating, building occupants are heated individually by directed radiant heaters, resulting in a considerably reduced heated space and significant heating energy savings. To support localized heating, a minimally-intrusive indoor occupant positioning system is described. The thesis then discusses occupant-level sensing (OLS) as the next frontier in building energy optimization. OLS captures the exact environmental conditions faced by each building occupant, using sensors that are carried by all building occupants. The information provided by OLS enables fine-grained optimization for unprecedented levels of energy efficiency and occupant comfort. The thesis also describes a retrofit

A hybrid Genetic Algorithm and Monte Carlo simulation approach to predict hourly energy consumption and generation by a cluster of Net Zero Energy Buildings

International Nuclear Information System (INIS)

Garshasbi, Samira; Kurnitski, Jarek; Mohammadi, Yousef

2016-01-01

Graphical abstract: The energy consumption and renewable generation in a cluster of NZEBs are modeled by a novel hybrid Genetic Algorithm and Monte Carlo simulation approach and used for the prediction of instantaneous and cumulative net energy balances and hourly amount of energy taken from and supplied to the central energy grid. - Highlights: • Hourly energy consumption and generation by a cluster of NZEBs was simulated. • Genetic Algorithm and Monte Carlo simulation approach were employed. • Dampening effect of energy used by a cluster of buildings was demonstrated. • Hourly amount of energy taken from and supplied to the grid was simulated. • Results showed that NZEB cluster was 63.5% grid dependant on annual bases. - Abstract: Employing a hybrid Genetic Algorithm (GA) and Monte Carlo (MC) simulation approach, energy consumption and renewable energy generation in a cluster of Net Zero Energy Buildings (NZEBs) was thoroughly investigated with hourly simulation. Moreover, the cumulative energy consumption and generation of the whole cluster and each individual building within the simulation space were accurately monitored and reported. The results indicate that the developed simulation algorithm is able to predict the total instantaneous and cumulative amount of energy taken from and supplied to the central energy grid over any time period. During the course of simulation, about 60–100% of total daily generated renewable energy was consumed by NZEBs and up to 40% of that was fed back into the central energy grid as surplus energy. The minimum grid dependency of the cluster was observed in June and July where 11.2% and 9.9% of the required electricity was supplied from the central energy grid, respectively. On the other hand, the NZEB cluster was strongly grid dependant in January and December by importing 70.7% and 76.1% of its required energy demand via the central energy grid, in the order given. Simulation results revealed that the cluster was 63

Implementing Occupant Behaviour in the Simulation of Building Energy Performance and Energy Flexibility: Development of Co-Simulation Framework and Case Study

DEFF Research Database (Denmark)

Li, Rongling; Wei, Feng; Zhao, Yang

2017-01-01

Occupant behaviour has a substantial impact on the prediction of building energy performance. To capture this impact, co-simulation is considered an effective approach. It is still a new method in need of more development. In this study, a co-simulation framework is established to couple Energy......Plus with Java via Functional Mock-up Interface (FMI) using the EnergyPlusToFMU software package. This method is applied to a case study of a single occupant office with control of lighting, plug load and thermostat. Two control scenarios are studied. These are occupancy and occupant behaviour based control (OC...

Assessment of Retrofitting Measures for a Large Historic Research Facility Using a Building Energy Simulation Model

Directory of Open Access Journals (Sweden)

Young Tae Chae

2016-06-01

Full Text Available A calibrated building simulation model was developed to assess the energy performance of a large historic research building. The complexity of space functions and operational conditions with limited availability of energy meters makes it hard to understand the end-used energy consumption in detail and to identify appropriate retrofitting options for reducing energy consumption and greenhouse gas (GHG emissions. An energy simulation model was developed to study the energy usage patterns not only at a building level, but also of the internal thermal zones, and system operations. The model was validated using site measurements of energy usage and a detailed audit of the internal load conditions, system operation, and space programs to minimize the discrepancy between the documented status and actual operational conditions. Based on the results of the calibrated model and end-used energy consumption, the study proposed potential energy conservation measures (ECMs for the building envelope, HVAC system operational methods, and system replacement. It also evaluated each ECM from the perspective of both energy and utility cost saving potentials to help retrofitting plan decision making. The study shows that the energy consumption of the building was highly dominated by the thermal requirements of laboratory spaces. Among other ECMs the demand management option of overriding the setpoint temperature is the most cost effective measure.

Summary of detailed energy audit and building simulation on archetype sustainable house, Woodbridge ON

Energy Technology Data Exchange (ETDEWEB)

Fung, A. [Ryerson Polytechnic Univ., Toronto, ON (Canada). Dept. of Mechanical and Industrial Engineering; Dembo, A.; Zhou, J. [Ryerson Polytechnic Univ., Toronto, ON (Canada). Dept. of Architectural Science

2009-07-01

This paper described energy and audit and building simulations conducted on an archetype sustainable house located in Woodbridge, Ontario. The house formed part of a project to construct low energy, sustainable house designs for mass production. The 2 houses formed a duplex. House A was designed using current best design practices, while house B was equipped with advanced and innovative technologies not commonly used in residential constructions. Natural Resources Canada's (NRCan) HOT2000 residential building simulation program was used to evaluate the performance of both houses in the duplex. The simulation program demonstrated that house B performed more efficiently than house A. However, neither houses met their designed values. Significantly larger space heating and cooling loads were identified. The program showed that additional weather-stripping around doors, and caulking around windows will help to reduce the amount of draft in the houses. Assessments are also needed to measure heat losses from the common wall in the basement. It was concluded that the energy performance of the house can be optimized by using the appropriate sealing techniques throughout the building envelope. 2 refs., 1 tab.

Energy Consumption and Indoor Environment Predicted by a Combination of Computational Fluid Dynamics and Building Energy Performance Simulation

DEFF Research Database (Denmark)

Nielsen, Peter Vilhelm

2003-01-01

An interconnection between a building energy performance simulation program and a Computational Fluid Dynamics program (CFD) for room air distribution is introduced for improvement of the predictions of both the energy consumption and the indoor environment.The article describes a calculation...

On variations of space-heating energy use in office buildings

International Nuclear Information System (INIS)

Lin, Hung-Wen; Hong, Tianzhen

2013-01-01

Highlights: • Space heating is the largest energy end use in the U.S. building sector. • A key design and operational parameters have the most influence on space heating. • Simulated results were benchmarked against actual results to analyze discrepancies. • Yearly weather changes have significant impact on space heating energy use. • Findings enable stakeholders to make better decisions on energy efficiency. - Abstract: Space heating is the largest energy end use, consuming more than seven quintillion joules of site energy annually in the U.S. building sector. A few recent studies showed discrepancies in simulated space-heating energy use among different building energy modeling programs, and the simulated results are suspected to be underpredicting reality. While various uncertainties are associated with building simulations, especially when simulations are performed by different modelers using different simulation programs for buildings with different configurations, it is crucial to identify and evaluate key driving factors to space-heating energy use in order to support the design and operation of low-energy buildings. In this study, 10 design and operation parameters for space-heating systems of two prototypical office buildings in each of three U.S. heating climates are identified and evaluated, using building simulations with EnergyPlus, to determine the most influential parameters and their impacts on variations of space-heating energy use. The influence of annual weather change on space-heating energy is also investigated using 30-year actual weather data. The simulated space-heating energy use is further benchmarked against those from similar actual office buildings in two U.S. commercial-building databases to better understand the discrepancies between simulated and actual energy use. In summary, variations of both the simulated and actual space-heating energy use of office buildings in all three heating climates can be very large. However

Structured building model reduction toward parallel simulation

Energy Technology Data Exchange (ETDEWEB)

Dobbs, Justin R. [Cornell University; Hencey, Brondon M. [Cornell University

2013-08-26

Building energy model reduction exchanges accuracy for improved simulation speed by reducing the number of dynamical equations. Parallel computing aims to improve simulation times without loss of accuracy but is poorly utilized by contemporary simulators and is inherently limited by inter-processor communication. This paper bridges these disparate techniques to implement efficient parallel building thermal simulation. We begin with a survey of three structured reduction approaches that compares their performance to a leading unstructured method. We then use structured model reduction to find thermal clusters in the building energy model and allocate processing resources. Experimental results demonstrate faster simulation and low error without any interprocessor communication.

Guidelines for developing efficient thermal conduction and storage models within building energy simulations

International Nuclear Information System (INIS)

Hillary, Jason; Walsh, Ed; Shah, Amip; Zhou, Rongliang; Walsh, Pat

2017-01-01

Improving building energy efficiency is of paramount importance due to the large proportion of energy consumed by thermal operations. Consequently, simulating a building's environment has gained popularity for assessing thermal comfort and design. The extended timeframes and large physical scales involved necessitate compact modelling approaches. The accuracy of such simulations is of chief concern, yet there is little guidance offered on achieving accurate solutions whilst mitigating prohibitive computational costs. Therefore, the present study addresses this deficit by providing clear guidance on discretisation levels required for achieving accurate but computationally inexpensive models. This is achieved by comparing numerical models of varying discretisation levels to benchmark analytical solutions with prediction accuracy assessed and reported in terms of governing dimensionless parameters, Biot and Fourier numbers, to ensure generality of findings. Furthermore, spatial and temporal discretisation errors are separated and assessed independently. Contour plots are presented to intuitively determine the optimal discretisation levels and time-steps required to achieve accurate thermal response predictions. Simulations derived from these contour plots were tested against various building conditions with excellent agreement observed throughout. Additionally, various scenarios are highlighted where the classical single lumped capacitance model can be applied for Biot numbers much greater than 0.1 without reducing accuracy. - Highlights: • Addressing the problems of inadequate discretisation within building energy models. • Accuracy of numerical models assessed against analytical solutions. • Fourier and Biot numbers used to provide generality of results for any material. • Contour plots offer intuitive way to interpret results for manual discretisation. • Results show proposed technique promising for automation of discretisation process.

Developing a new library of materials and structural elements for the simulative evaluation of buildings' energy performance

Energy Technology Data Exchange (ETDEWEB)

Papadopoulos, Agis M.; Oxizidis, Simos; Papathanasiou, Luciano [Laboratory of Heat Transfer and Environmental Engineering, Department of Mechanical Engineering, Aristotle University Thessaloniki, P.O. Box 483, Thessaloniki 54124 (Greece)

2008-05-15

Contemporary building energy simulation programs are not only used by researchers but also are common tools in the hands of engineers and architects. Most of them are using databases of materials and structural elements, with characteristics originating from the country or the broader region where the specific program was developed. Thus, often the particularities met in other countries are not considered. Such a database of materials and constructions systematically used in the Greek building sector was developed for use with the simulation program EnergyPlus, which has become quite popular over the last years. In order to determine the applicability of the database, the energy behaviour of a typical multistory, multifamily building was simulated, having the exact materials and structural elements and patterns used in Greece. Furthermore, different thicknesses of insulation were simulated, corresponding to local climatic conditions and, even more important, to different dates of the building's construction. The results are presented and discussed in this paper. (author)

Modeling and simulation to determine the potential energy savings by implementing cold thermal energy storage system in office buildings

International Nuclear Information System (INIS)

Rismanchi, B.; Saidur, R.; Masjuki, H.H.; Mahlia, T.M.I.

2013-01-01

Highlights: • Simulating the CTES system behavior based on Malaysian climate. • Almost 65% of power is used for cooling for cooling the office buildings, every day. • The baseline shows an acceptable match with real data from the fieldwork. • Overall, the energy used for full load storage is much than the conventional system. • The load levelling storage strategy has 3.7% lower energy demand. - Abstract: In Malaysia, air conditioning (AC) systems are considered as the major energy consumers in office buildings with almost 57% share. During the past decade, cold thermal energy storage (CTES) systems have been widely used for their significant economic benefits. However, there were always doubts about their energy saving possibilities. The main objective of the present work is to develop a computer model to determine the potential energy savings of implementing CTES systems in Malaysia. A case study building has been selected to determine the energy consumption pattern of an office building. In the first step the building baseline model was developed and validated with the recorded data from the fieldwork. Once the simulation results reach an acceptable accuracy, different CTES system configuration was added to the model to predict their energy consumption pattern. It was found that the overall energy used by the full load storage strategy is considerably more than the conventional system. However, by applying the load leveling storage strategy, and considering its benefits to reduce the air handling unit size and reducing the pumping power, the overall energy usage was almost 4% lower than the non-storage system. Although utilizing CTES systems cannot reduce the total energy consumption considerably, but it has several outstanding benefits such as cost saving, bringing balance in the grid system, reducing the overall fuel consumption in the power plants and consequently reducing to total carbon footprint

Hourly test reference weather data in the changing climate of Finland for building energy simulations

Directory of Open Access Journals (Sweden)

Kirsti Jylhä

2015-09-01

Full Text Available Dynamic building energy simulations need hourly weather data as input. The same high temporal resolution is required for assessments of future heating and cooling energy demand. The data presented in this article concern current typical values and estimated future changes in outdoor air temperature, wind speed, relative humidity and global, diffuse and normal solar radiation components. Simulated annual and seasonal delivered energy consumptions for heating of spaces, heating of ventilation supply air and cooling of spaces in the current and future climatic conditions are also presented for an example house, with district heating and a mechanical space cooling system. We provide details on how the synthetic future weather files were created and utilised as input data for dynamic building energy simulations by the IDA Indoor Climate and Energy program and also for calculations of heating and cooling degree-day sums. The information supplied here is related to the research article titled “Energy demand for the heating and cooling of residential houses in Finland in a changing climate” [1].

Building energy performance analysis by an in-house developed dynamic simulation code: An investigation for different case studies

International Nuclear Information System (INIS)

Buonomano, Annamaria; Palombo, Adolfo

2014-01-01

Highlights: • A new dynamic simulation code for building energy performance analysis is presented. • The thermal behavior of each building element is modeled by a thermal RC network. • The physical models implemented in the code are illustrated. • The code was validated by the BESTEST standard procedure. • We investigate residential buildings, offices and stores in different climates. - Abstract: A novel dynamic simulation model for the building envelope energy performance analysis is presented in this paper. This tool helps the investigation of many new building technologies to increase the system energy efficiency and it can be carried out for scientific research purposes. In addition to the yearly heating and cooling load and energy demand, the obtained output is the dynamic temperature profile of indoor air and surfaces and the dynamic profile of the thermal fluxes through the building elements. The presented simulation model is also validated through the BESTEST standard procedure. Several new case studies are developed for assessing, through the presented code, the energy performance of three different building envelopes with several different weather conditions. In particular, dwelling and commercial buildings are analysed. Light and heavyweight envelopes as well as different glazed surfaces areas have been used for every case study. With the achieved results interesting design and operating guidelines can be obtained. Such data have been also compared vs. those calculated by TRNSYS and EnergyPlus. The detected deviation of the obtained results vs. those of such standard tools are almost always lower than 10%

Building envelope influence on the annual energy performance in office buildings

Directory of Open Access Journals (Sweden)

Harmati Norbert L.

2016-01-01

Full Text Available The objective of the research is to determine the quantitative influence of building envelope on the annual heating and cooling energy demand in office buildings demonstrated on a reference office-tower building located in Novi Sad, Serbia. The investigation intended to find preferable and applicable solutions for energy performance improvement in currently inefficient office buildings. A comparative and evaluative analysis was performed among the heating energy expenses and simulated values from the multi-zone model designed in EnergyPlus engine. The research determines an improved window to wall ratio using dynamic daylight simulation and presents the influence of glazing parameters (U-value, Solar heat gain coefficient - SHGC on the annual energy performance. Findings presented window to wall ratio reduction down to 30% and point out the significance of the SHGC parameter on the overall energy performance of buildings with high internal loads. The calculation of the air-ventilation energy demand according to EN 15251 is included respectively. Results offer effective methods for energy performance improvement in temperate climate conditions.

Comparison of Building Energy Modeling Programs: Building Loads

Energy Technology Data Exchange (ETDEWEB)

Zhu, Dandan [Tsinghua Univ., Beijing (China); Hong, Tianzhen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States); Yan, Da [Tsinghua Univ., Beijing (China); Wang, Chuang [Tsinghua Univ., Beijing (China)

2012-06-01

This technical report presented the methodologies, processes, and results of comparing three Building Energy Modeling Programs (BEMPs) for load calculations: EnergyPlus, DeST and DOE-2.1E. This joint effort, between Lawrence Berkeley National Laboratory, USA and Tsinghua University, China, was part of research projects under the US-China Clean Energy Research Center on Building Energy Efficiency (CERC-BEE). Energy Foundation, an industrial partner of CERC-BEE, was the co-sponsor of this study work. It is widely known that large discrepancies in simulation results can exist between different BEMPs. The result is a lack of confidence in building simulation amongst many users and stakeholders. In the fields of building energy code development and energy labeling programs where building simulation plays a key role, there are also confusing and misleading claims that some BEMPs are better than others. In order to address these problems, it is essential to identify and understand differences between widely-used BEMPs, and the impact of these differences on load simulation results, by detailed comparisons of these BEMPs from source code to results. The primary goal of this work was to research methods and processes that would allow a thorough scientific comparison of the BEMPs. The secondary goal was to provide a list of strengths and weaknesses for each BEMP, based on in-depth understandings of their modeling capabilities, mathematical algorithms, advantages and limitations. This is to guide the use of BEMPs in the design and retrofit of buildings, especially to support China’s building energy standard development and energy labeling program. The research findings could also serve as a good reference to improve the modeling capabilities and applications of the three BEMPs. The methodologies, processes, and analyses employed in the comparison work could also be used to compare other programs. The load calculation method of each program was analyzed and compared to

Energy efficiency evaluation of hospital building office

Science.gov (United States)

Fitriani, Indah; Sangadji, Senot; Kristiawan, S. A.

2017-01-01

One of the strategy employed in building design is reducing energy consumption while maintaining the best comfort zone in building indoor climate. The first step to improve office buildings energy performance by evaluating its existing energy usage using energy consumption intensity (Intensitas Konsumsi Energi, IKE) index. Energy evaluation of office building for hospital dr. Sayidiman at Kabupaten Magetan has been carried out in the initial investigation. The office building is operated with active cooling (air conditioning, AC) and use limited daylighting which consumes 14.61 kWh/m2/month. This IKE value is attributed into a slightly inefficient category. Further investigation was carried out by modeling and simulating thermal energy load and room lighting in every building zone using of Ecotect from Autodesk. Three scenarios of building energy and lighting retrofit have been performed simulating representing energy efficiency using cross ventilation, room openings, and passive cooling. The results of the numerical simulation indicate that the third scenario by employing additional windows, reflector media and skylight exhibit the best result and in accordance with SNI 03-6575-2001 lighting standard. Total thermal load of the existing building which includes fabric gains, indirect solar gains, direct solar gains, ventilation fans, internal gains, inter-zonal gains and cooling load were 162,145.40 kWh. Based on the three scenarios, the thermal load value (kWh) obtained was lowest achieved scenario 2 with the thermal value of 117,539.08 kWh.The final results are interpreted from the total energy emissions evaluated using the Ecotect software, the heating and cooling demand value and specific design of the windows are important factors to determine the energy efficiency of the buildings.

Energy efficiency evaluation of hospital building office

International Nuclear Information System (INIS)

Fitriani, Indah; Sangadji, Senot; Kristiawan, S.A.

2017-01-01

One of the strategy employed in building design is reducing energy consumption while maintaining the best comfort zone in building indoor climate. The first step to improve office buildings energy performance by evaluating its existing energy usage using energy consumption intensity (Intensitas Konsumsi Energi, IKE) index. Energy evaluation of office building for hospital dr. Sayidiman at Kabupaten Magetan has been carried out in the initial investigation. The office building is operated with active cooling (air conditioning, AC) and use limited daylighting which consumes 14.61 kWh/m2/month. This IKE value is attributed into a slightly inefficient category. Further investigation was carried out by modeling and simulating thermal energy load and room lighting in every building zone using of Ecotect from Autodesk. Three scenarios of building energy and lighting retrofit have been performed simulating representing energy efficiency using cross ventilation, room openings, and passive cooling. The results of the numerical simulation indicate that the third scenario by employing additional windows, reflector media and skylight exhibit the best result and in accordance with SNI 03-6575-2001 lighting standard. Total thermal load of the existing building which includes fabric gains, indirect solar gains, direct solar gains, ventilation fans, internal gains, inter-zonal gains and cooling load were 162,145.40 kWh. Based on the three scenarios, the thermal load value (kWh) obtained was lowest achieved scenario 2 with the thermal value of 117,539.08 kWh.The final results are interpreted from the total energy emissions evaluated using the Ecotect software, the heating and cooling demand value and specific design of the windows are important factors to determine the energy efficiency of the buildings. (paper)

Achieving Actionable Results from Available Inputs: Metamodels Take Building Energy Simulations One Step Further

Energy Technology Data Exchange (ETDEWEB)

Horsey, Henry; Fleming, Katherine; Ball, Brian; Long, Nicholas

2016-08-26

Modeling commercial building energy usage can be a difficult and time-consuming task. The increasing prevalence of optimization algorithms provides one path for reducing the time and difficulty. Many use cases remain, however, where information regarding whole-building energy usage is valuable, but the time and expertise required to run and post-process a large number of building energy simulations is intractable. A relatively underutilized option to accurately estimate building energy consumption in real time is to pre-compute large datasets of potential building energy models, and use the set of results to quickly and efficiently provide highly accurate data. This process is called metamodeling. In this paper, two case studies are presented demonstrating the successful applications of metamodeling using the open-source OpenStudio Analysis Framework. The first case study involves the U.S. Department of Energy's Asset Score Tool, specifically the Preview Asset Score Tool, which is designed to give nontechnical users a near-instantaneous estimated range of expected results based on building system-level inputs. The second case study involves estimating the potential demand response capabilities of retail buildings in Colorado. The metamodel developed in this second application not only allows for estimation of a single building's expected performance, but also can be combined with public data to estimate the aggregate DR potential across various geographic (county and state) scales. In both case studies, the unique advantages of pre-computation allow building energy models to take the place of topdown actuarial evaluations. This paper ends by exploring the benefits of using metamodels and then examines the cost-effectiveness of this approach.

Commercial Building Energy Saver: An energy retrofit analysis toolkit

International Nuclear Information System (INIS)

Hong, Tianzhen; Piette, Mary Ann; Chen, Yixing; Lee, Sang Hoon; Taylor-Lange, Sarah C.; Zhang, Rongpeng; Sun, Kaiyu; Price, Phillip

2015-01-01

Highlights: • Commercial Building Energy Saver is a powerful toolkit for energy retrofit analysis. • CBES provides benchmarking, load shape analysis, and model-based retrofit assessment. • CBES covers 7 building types, 6 vintages, 16 climates, and 100 energy measures. • CBES includes a web app, API, and a database of energy efficiency performance. • CBES API can be extended and integrated with third party energy software tools. - Abstract: Small commercial buildings in the United States consume 47% of the total primary energy of the buildings sector. Retrofitting small and medium commercial buildings poses a huge challenge for owners because they usually lack the expertise and resources to identify and evaluate cost-effective energy retrofit strategies. This paper presents the Commercial Building Energy Saver (CBES), an energy retrofit analysis toolkit, which calculates the energy use of a building, identifies and evaluates retrofit measures in terms of energy savings, energy cost savings and payback. The CBES Toolkit includes a web app (APP) for end users and the CBES Application Programming Interface (API) for integrating CBES with other energy software tools. The toolkit provides a rich set of features including: (1) Energy Benchmarking providing an Energy Star score, (2) Load Shape Analysis to identify potential building operation improvements, (3) Preliminary Retrofit Analysis which uses a custom developed pre-simulated database and, (4) Detailed Retrofit Analysis which utilizes real-time EnergyPlus simulations. CBES includes 100 configurable energy conservation measures (ECMs) that encompass IAQ, technical performance and cost data, for assessing 7 different prototype buildings in 16 climate zones in California and 6 vintages. A case study of a small office building demonstrates the use of the toolkit for retrofit analysis. The development of CBES provides a new contribution to the field by providing a straightforward and uncomplicated decision

Building America House Simulation Protocols

Energy Technology Data Exchange (ETDEWEB)

Hendron, Robert [National Renewable Energy Lab. (NREL), Golden, CO (United States); Engebrecht, Cheryn [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2010-09-01

The House Simulation Protocol document was developed to track and manage progress toward Building America's multi-year, average whole-building energy reduction research goals for new construction and existing homes, using a consistent analytical reference point. This report summarizes the guidelines for developing and reporting these analytical results in a consistent and meaningful manner for all home energy uses using standard operating conditions.

Methodology for Modeling Building Energy Performance across the Commercial Sector

Energy Technology Data Exchange (ETDEWEB)

Griffith, B.; Long, N.; Torcellini, P.; Judkoff, R.; Crawley, D.; Ryan, J.

2008-03-01

This report uses EnergyPlus simulations of each building in the 2003 Commercial Buildings Energy Consumption Survey (CBECS) to document and demonstrate bottom-up methods of modeling the entire U.S. commercial buildings sector (EIA 2006). The ability to use a whole-building simulation tool to model the entire sector is of interest because the energy models enable us to answer subsequent 'what-if' questions that involve technologies and practices related to energy. This report documents how the whole-building models were generated from the building characteristics in 2003 CBECS and compares the simulation results to the survey data for energy use.

Computational fluid dynamics simulation of indoor climate in low energy buildings: Computational set up

Directory of Open Access Journals (Sweden)

Risberg Daniel

2017-01-01

Full Text Available In this paper CFD was used for simulation of the indoor climate in a part of a low energy building. The focus of the work was on investigating the computational set up, such as grid size and boundary conditions in order to solve the indoor climate problems in an accurate way. Future work is to model a complete building, with reasonable calculation time and accuracy. A limited number of grid elements and knowledge of boundary settings are therefore essential. An accurate grid edge size of around 0.1 m was enough to predict the climate according to a grid independency study. Different turbulence models were compared with only small differences in the indoor air velocities and temperatures. The models show that radiation between building surfaces has a large impact on the temperature field inside the building, with the largest differences at the floor level. Simplifying the simulations by modelling the radiator as a surface in the outer wall of the room is appropriate for the calculations. The overall indoor climate is finally compared between three different cases for the outdoor air temperature. The results show a good indoor climate for a low energy building all around the year.

An applied artificial intelligence approach towards assessing building performance simulation tools

Energy Technology Data Exchange (ETDEWEB)

Yezioro, Abraham [Faculty of Architecture and Town Planning, Technion IIT (Israel); Dong, Bing [Center for Building Performance and Diagnostics, School of Architecture, Carnegie Mellon University (United States); Leite, Fernanda [Department of Civil and Environmental Engineering, Carnegie Mellon University (United States)

2008-07-01

With the development of modern computer technology, a large amount of building energy simulation tools is available in the market. When choosing which simulation tool to use in a project, the user must consider the tool's accuracy and reliability, considering the building information they have at hand, which will serve as input for the tool. This paper presents an approach towards assessing building performance simulation results to actual measurements, using artificial neural networks (ANN) for predicting building energy performance. Training and testing of the ANN were carried out with energy consumption data acquired for 1 week in the case building called the Solar House. The predicted results show a good fitness with the mathematical model with a mean absolute error of 0.9%. Moreover, four building simulation tools were selected in this study in order to compare their results with the ANN predicted energy consumption: Energy{sub 1}0, Green Building Studio web tool, eQuest and EnergyPlus. The results showed that the more detailed simulation tools have the best simulation performance in terms of heating and cooling electricity consumption within 3% of mean absolute error. (author)

PV (photovoltaics) performance evaluation and simulation-based energy yield prediction for tropical buildings

International Nuclear Information System (INIS)

Saber, Esmail M.; Lee, Siew Eang; Manthapuri, Sumanth; Yi, Wang; Deb, Chirag

2014-01-01

Air pollution and climate change increased the importance of renewable energy resources like solar energy in the last decades. Rack-mounted PhotoVoltaics (PV) and Building Integrated PhotoVoltaics (BIPV) are the most common photovoltaic systems which convert incident solar radiation on façade or surrounding area to electricity. In this paper the performance of different solar cell types is evaluated for the tropical weather of Singapore. As a case study, on-site measured data of PV systems implemented in a zero energy building in Singapore, is analyzed. Different types of PV systems (silicon wafer and thin film) have been installed on rooftop, façade, car park shelter, railing and etc. The impact of different solar cell generations, arrays environmental conditions (no shading, dappled shading, full shading), orientation (South, North, East or West facing) and inclination (between PV module and horizontal direction) is investigated on performance of modules. In the second stage of research, the whole PV systems in the case study are simulated in EnergyPlus energy simulation software with several PV performance models including Simple, Equivalent one-diode and Sandia. The predicted results by different models are compared with measured data and the validated model is used to provide simulation-based energy yield predictions for wide ranges of scenarios. It has been concluded that orientation of low-slope rooftop PV has negligible impact on annual energy yield but in case of PV external sunshade, east façade and panel slope of 30–40° are the most suitable location and inclination. - Highlights: • Characteristics of PV systems in tropics are analyzed in depth. • The ambiguity toward amorphous panel energy yield in tropics is discussed. • Equivalent-one diode and Sandia models can fairly predict the energy yield. • A general guideline is provided to estimate the energy yield of PV systems in tropics

Simulation Speed Analysis and Improvements of Modelica Models for Building Energy Simulation

Energy Technology Data Exchange (ETDEWEB)

Jorissen, Filip; Wetter, Michael; Helsen, Lieve

2015-09-21

This paper presents an approach for speeding up Modelica models. Insight is provided into how Modelica models are solved and what determines the tool’s computational speed. Aspects such as algebraic loops, code efficiency and integrator choice are discussed. This is illustrated using simple building simulation examples and Dymola. The generality of the work is in some cases verified using OpenModelica. Using this approach, a medium sized office building including building envelope, heating ventilation and air conditioning (HVAC) systems and control strategy can be simulated at a speed five hundred times faster than real time.

Description of occupant behaviour in building energy simulation: state-of-art and concepts for improvements

DEFF Research Database (Denmark)

Fabi, Valentina; Andersen, Rune Vinther; Corgnati, Stefano Paolo

2011-01-01

of basic assumptions that affect the results. Therefore, the calculated energy performance may differ significantly from the real energy consumption. One of the key reasons is the current inability to properly model occupant behaviour and to quantify the associated uncertainties in building performance...... predictions. By consequence, a better description of parameters related to occupant behaviour is highly required. In this paper, the state of art in occupant behaviour modelling within energy simulation tools is analysed and some concepts related to possible improvements of simulation tools are proposed...

Accelerating the energy retrofit of commercial buildings using a database of energy efficiency performance

International Nuclear Information System (INIS)

Lee, Sang Hoon; Hong, Tianzhen; Piette, Mary Ann; Sawaya, Geof; Chen, Yixing; Taylor-Lange, Sarah C.

2015-01-01

Small and medium-sized commercial buildings can be retrofitted to significantly reduce their energy use, however it is a huge challenge as owners usually lack of the expertise and resources to conduct detailed on-site energy audit to identify and evaluate cost-effective energy technologies. This study presents a DEEP (database of energy efficiency performance) that provides a direct resource for quick retrofit analysis of commercial buildings. DEEP, compiled from the results of about ten million EnergyPlus simulations, enables an easy screening of ECMs (energy conservation measures) and retrofit analysis. The simulations utilize prototype models representative of small and mid-size offices and retails in California climates. In the formulation of DEEP, large scale EnergyPlus simulations were conducted on high performance computing clusters to evaluate hundreds of individual and packaged ECMs covering envelope, lighting, heating, ventilation, air-conditioning, plug-loads, and service hot water. The architecture and simulation environment to create DEEP is flexible and can expand to cover additional building types, additional climates, and new ECMs. In this study DEEP is integrated into a web-based retrofit toolkit, the Commercial Building Energy Saver, which provides a platform for energy retrofit decision making by querying DEEP and unearthing recommended ECMs, their estimated energy savings and financial payback. - Highlights: • A DEEP (database of energy efficiency performance) supports building retrofit. • DEEP is an SQL database with pre-simulated results from 10 million EnergyPlus runs. • DEEP covers 7 building types, 6 vintages, 16 climates, and 100 energy measures. • DEEP accelerates retrofit of small commercial buildings to save energy use and cost. • DEEP can be expanded and integrated with third-party energy software tools.

A Real-Time Energy Consumption Simulation and Comparison of Buildings in Different Construction Years in the Olympic Central Area in Beijing

Directory of Open Access Journals (Sweden)

Chen Xu

2017-12-01

Full Text Available Energy consumed the in urban sector accounts for a large proportion of total world delivered energy consumption. Residential building energy consumption is an important part of urban energy consumption. However, there are few studies focused on this issue and that have simulated the energy consumption of residential buildings using questionnaire data. In this research, an eQUEST study was conducted for different residential buildings in the Olympic Central Area in Beijing. Real-time meteorological observation data and an actual energy consumption schedule generated by questionnaire data were used to improve the eQUEST model in the absence of actual energy consumption data. The simulated total energy consumption of residential buildings in the case area in 2015 is 21,262.28 tce, and the average annual energy consumption per unit area is 20.09 kgce/(m2·a. Space heating accounted for 45% of the total energy consumption as the highest proportion, and the second highest was household appliances, which accounted for 20%. The results showed that old residential buildings, multi-storey buildings and large-sized apartment buildings consume more energy. The internal units, building height, per capita construction area, the number of occupants and length of power use had significant impact on residential energy consumption. The result of this study will provide practical reference for energy saving reconstruction of residential buildings in Beijing.

Energy Simulation of a Holographic PVT Concentrating System for Building Integration Applications

Directory of Open Access Journals (Sweden)

Julia Marín-Sáez

2016-07-01

Full Text Available A building integrated holographic concentrating photovoltaic-thermal system has been optically and energetically simulated. The system has been designed to be superimposed into a solar shading louvre; in this way the concentrating unit takes profit of the solar altitude tracking, which the shading blinds already have, to increase system performance. A dynamic energy simulation has been conducted in two different locations—Sde Boker (Israel and Avignon (France—both with adequate annual irradiances for solar applications, but with different weather and energy demand characteristics. The simulation engine utilized has been TRNSYS, coupled with MATLAB (where the ray-tracing algorithm to simulate the holographic optical performance has been implemented. The concentrator achieves annual mean optical efficiencies of 30.3% for Sde Boker and 43.0% for the case of Avignon. Regarding the energy production, in both locations the thermal energy produced meets almost 100% of the domestic hot water demand as this has been considered a priority in the system control. On the other hand, the space heating demands are covered by a percentage ranging from 15% (Avignon to 20% (Sde Boker. Finally, the electricity produced in both places covers 7.4% of the electrical demand profile for Sde Boker and 9.1% for Avignon.

Proceedings of eSim 2006 : IBPSA-Canada's 4. biennial building performance simulation conference

International Nuclear Information System (INIS)

Kesik, T.

2006-01-01

This conference was attended by professionals, academics and students interested in promoting the science of building performance simulation in order to optimize design, construction, operation and maintenance of new and existing buildings around the world. This biennial conference and exhibition covered all topics related to computerized simulation of a building's energy performance and energy efficiency. Computerized simulation is widely used to predict the environmental performance of buildings during all stages of a building's life cycle, from the design, commissioning, construction, occupancy and management stages. Newly developed simulation methods for optimal comfort in new and existing buildings were evaluated. The themes of the conference were: recent developments for modelling the physical processes relevant to buildings; algorithms for modelling conventional and innovative HVAC systems; methods for modelling whole-building performance; building simulation software development; the use of building simulation tools in code compliance; moving simulation into practice; validation of building simulation software; architectural design; and optimization approaches in building design. The conference also covered the modeling of energy supply systems with reference to renewable energy sources such as ground source heat pumps or hybrid systems incorporating solar energy. The conference featured 32 presentations, of which 28 have been catalogued separately for inclusion in this database. refs., tabs., figs

First Swiss building and urban simulation conference. Conference proceedings

Energy Technology Data Exchange (ETDEWEB)

Zweifel, G.; Citherlet, S.; Afjei, T.; Pahud, D.; Robinson, D.; Schaelin, A.

2010-07-01

These contributions presented at a conference, held in 2009 in Horw, near Lucerne, Switzerland, deal with the simulation of building technical services. Three contribution blocks dealt with thermal and heating, ventilation and air-conditioning (HVAC) simulation, airflow and stochastic modelling and urban simulation. In the thermal and HVAC simulation session, the potential and limitations of building energy performance simulation is examined from an engineering perspective, a parametric study of an air heat exchanger for the cooling of buildings is presented and a comparison of measured and estimated electric energy use and the impact of assumed occupancy patterns is made. Contributions on standard solutions for energy efficient heating and cooling with heat pumps, the validation and certification of dynamic building simulation tools, standards and tools for the energy performance of buildings with a simple chiller model and the system-simulation of a central solar heating plant with seasonal duct storage in Geneva, Switzerland, are presented. In the airflow and stochastic modelling session, the optimisation of air flow in operating theatres is examined, and air-flow phenomena in flats are explained with illustrations of computational fluid dynamics (CFD). Also, the comparison of test reference years to stochastically generated time series and a comprehensive stochastic model of window usage are discussed. Contributions on the simulation of air-flow patterns and wind loads on facades and the choice of appropriate simulation techniques for the thermal analysis of double skin facades complete the session. In the final Urban Simulation session, a new CFD approach for urban flow and pollution dispersion simulation is presented, a comprehensive micro-simulation of resource flows for sustainable urban planning, multi-scale modelling of the urban climate and the optimisation of urban energy demands using an evolutionary algorithm are discussed.

Building America House Simulation Protocols (Revised)

Energy Technology Data Exchange (ETDEWEB)

Hendron, R.; Engebrecht, C.

2010-10-01

The House Simulation Protocol document was developed to track and manage progress toward Building America's multi-year, average whole-building energy reduction research goals for new construction and existing homes, using a consistent analytical reference point. This report summarizes the guidelines for developing and reporting these analytical results in a consistent and meaningful manner for all home energy uses using standard operating conditions.

Comparing internal and external run-time coupling of CFD and building energy simulation software

NARCIS (Netherlands)

Djunaedy, E.; Hensen, J.L.M.; Loomans, M.G.L.C.

2004-01-01

This paper describes a comparison between internal and external run-time coupling of CFD and building energy simulation software. Internal coupling can be seen as the "traditional" way of developing software, i.e. the capabilities of existing software are expanded by merging codes. With external

Simulated thermal energy demand and actual energy consumption in refurbished and non-refurbished buildings

Science.gov (United States)

Ilie, C. A.; Visa, I.; Duta, A.

2016-08-01

The EU legal frame imposes the Nearly Zero Energy Buildings (nZEB) status to any new public building starting with January 1st, 2019 and for any other new building starting with 2021. Basically, nZEB represents a Low Energy Building (LEB) that covers more than half of the energy demand by using renewable energy systems installed on or close to it. Thus, two steps have to be followed in developing nZEB: (1) reaching the LEB status through state- of-the art architectural and construction solutions (for the new buildings) or through refurbishing for the already existent buildings, followed by (2) implementing renewables; in Romania, over 65% of the energy demand in a building is directly linked to heating, domestic hot water (DHW), and - in certain areas - for cooling. Thus, effort should be directed to reduce the thermal energy demand to be further covered by using clean and affordable systems: solar- thermal systems, heat pumps, biomass, etc. or their hybrid combinations. Obviously this demand is influenced by the onsite climatic profile and by the building performance. An almost worst case scenario is approached in the paper, considering a community implemented in a mountain area, with cold and long winters and mild summers (Odorheiul Secuiesc city, Harghita county, Romania). Three representative types of buildings are analysed: multi-family households (in blocks of flats), single-family houses and administrative buildings. For the first two types, old and refurbished buildings were comparatively discussed.

ImBuild: Impact of building energy efficiency programs

Energy Technology Data Exchange (ETDEWEB)

Scott, M.J.; Hostick, D.J.; Belzer, D.B.

1998-04-01

As part of measuring the impact of government programs on improving the energy efficiency of the Nation`s building stock, the Department of Energy Office of Building Technology, State and Community Programs (BTS) is interested in assessing the economic impacts of its portfolio of programs, specifically the potential impact on national employment and income. The special-purpose version of the IMPLAN model used in this study is called ImBuild. In comparison with simple economic multiplier approaches, such as Department of Commerce RIMS 2 system, ImBuild allows for more complete and automated analysis of the economic impacts of energy efficiency investments in buildings. ImBuild is also easier to use than existing macroeconomic simulation models. The authors conducted an analysis of three sample BTS energy programs: the residential generator-absorber heat exchange gas heat pump (GAX heat pump), the low power sulfur lamp (LPSL) in residential and commercial applications, and the Building America program. The GAX heat pump would address the market for the high-efficiency residential combined heating and cooling systems. The LPSL would replace some highly efficient fluorescent commercial lighting. Building America seeks to improve the energy efficiency of new factory-built, modular, manufactured, and small-volume, site-built homes through use of systems engineering concepts and early incorporation of new products and processes, and by increasing the demand for more energy-efficient homes. The authors analyze a scenario for market penetration of each of these technologies devised for BTS programs reported in the BTS GPRA Metrics Estimates, FY99 Budget Request, December 19, 1997. 46 figs., 4 tabs.

A View on Future Building System Modeling and Simulation

Energy Technology Data Exchange (ETDEWEB)

Wetter, Michael

2011-04-01

This chapter presents what a future environment for building system modeling and simulation may look like. As buildings continue to require increased performance and better comfort, their energy and control systems are becoming more integrated and complex. We therefore focus in this chapter on the modeling, simulation and analysis of building energy and control systems. Such systems can be classified as heterogeneous systems because they involve multiple domains, such as thermodynamics, fluid dynamics, heat and mass transfer, electrical systems, control systems and communication systems. Also, they typically involve multiple temporal and spatial scales, and their evolution can be described by coupled differential equations, discrete equations and events. Modeling and simulating such systems requires a higher level of abstraction and modularisation to manage the increased complexity compared to what is used in today's building simulation programs. Therefore, the trend towards more integrated building systems is likely to be a driving force for changing the status quo of today's building simulation programs. Thischapter discusses evolving modeling requirements and outlines a path toward a future environment for modeling and simulation of heterogeneous building systems.A range of topics that would require many additional pages of discussion has been omitted. Examples include computational fluid dynamics for air and particle flow in and around buildings, people movement, daylight simulation, uncertainty propagation and optimisation methods for building design and controls. For different discussions and perspectives on the future of building modeling and simulation, we refer to Sahlin (2000), Augenbroe (2001) and Malkawi and Augenbroe (2004).

Predicting energy performance of a net-zero energy building: A statistical approach

International Nuclear Information System (INIS)

Kneifel, Joshua; Webb, David

2016-01-01

Highlights: • A regression model is applied to actual energy data from a net-zero energy building. • The model is validated through a rigorous statistical analysis. • Comparisons are made between model predictions and those of a physics-based model. • The model is a viable baseline for evaluating future models from the energy data. - Abstract: Performance-based building requirements have become more prevalent because it gives freedom in building design while still maintaining or exceeding the energy performance required by prescriptive-based requirements. In order to determine if building designs reach target energy efficiency improvements, it is necessary to estimate the energy performance of a building using predictive models and different weather conditions. Physics-based whole building energy simulation modeling is the most common approach. However, these physics-based models include underlying assumptions and require significant amounts of information in order to specify the input parameter values. An alternative approach to test the performance of a building is to develop a statistically derived predictive regression model using post-occupancy data that can accurately predict energy consumption and production based on a few common weather-based factors, thus requiring less information than simulation models. A regression model based on measured data should be able to predict energy performance of a building for a given day as long as the weather conditions are similar to those during the data collection time frame. This article uses data from the National Institute of Standards and Technology (NIST) Net-Zero Energy Residential Test Facility (NZERTF) to develop and validate a regression model to predict the energy performance of the NZERTF using two weather variables aggregated to the daily level, applies the model to estimate the energy performance of hypothetical NZERTFs located in different cities in the Mixed-Humid Climate Zone, and compares these

Simulation of an active solar energy system integrated in a passive building in order to obtain system efficiency

Science.gov (United States)

Ceacaru, Mihai C.

2012-11-01

In this work we present a simulation of an active solar energy system. This system belongs to the first passive office building (2086 square meters) in Romania and it is used for water heating consumption. This office building was opened in February 2009 and was built based on passive house design solutions. For this simulation, we use Solar Water Heating module, which belongs to the software RETSCREEN and this simulation is done for several cities in Romania. Results obtained will be compared graphically.

Modelica-based Modeling and Simulation to Support Research and Development in Building Energy and Control Systems

Energy Technology Data Exchange (ETDEWEB)

Wetter, Michael

2009-02-12

Traditional building simulation programs possess attributes that make them difficult to use for the design and analysis of building energy and control systems and for the support of model-based research and development of systems that may not already be implemented in these programs. This article presents characteristic features of such applications, and it shows how equation-based object-oriented modelling can meet requirements that arise in such applications. Next, the implementation of an open-source component model library for building energy systems is presented. The library has been developed using the equation-based object-oriented Modelica modelling language. Technical challenges of modelling and simulating such systems are discussed. Research needs are presented to make this technology accessible to user groups that have more stringent requirements with respect to the numerical robustness of simulation than a research community may have. Two examples are presented in which models from the here described library were used. The first example describes the design of a controller for a nonlinear model of a heating coil using model reduction and frequency domain analysis. The second example describes the tuning of control parameters for a static pressure reset controller of a variable air volume flow system. The tuning has been done by solving a non-convex optimization problem that minimizes fan energy subject to state constraints.

External shading devices for energy efficient building

Science.gov (United States)

Shahdan, M. S.; Ahmad, S. S.; Hussin, M. A.

2018-02-01

External shading devices on a building façade is an important passive design strategy as they reduce solar radiation. Although studies have proven the benefits of external shading devices, many are designed solely for aesthetic purposes without fully considering its high potential to reduce solar radiation and glare. Furthermore, explorations into shading devices by the design team are mostly left too late in the design development phases. Hence, the paper looks into the effectiveness of external shading devices on a building towards more energy efficient building. The study aims to analyse the effects of various configurations of external shading devices towards the energy consumption of a case study building based on computer simulations. This study uses Building Information Modelling (BIM) through Autodesk Revit software as simulation tool. The constant variables for the simulation are the orientation of the building, types of glazing used by the building and the internal loads of the building. Whereas, the manipulated variable is the types of shading device used. The data were sorted according to the categories and translated into a chart. Analysis of the findings indicate that shading devices with different configurations show significant results in the energy consumption and the best configuration is the egg-crate shading devices. The study recommends that the consideration for shading device as a passive design strategy needs to be developed at the early stage of the building design.

Empirical Validation of Building Simulation Software : Modeling of Double Facades

DEFF Research Database (Denmark)

Kalyanova, Olena; Heiselberg, Per

The work described in this report is the result of a collaborative effort of members of the International Energy Agency (IEA), Task 34/43: Testing and validation of building energy simulation tools experts group.......The work described in this report is the result of a collaborative effort of members of the International Energy Agency (IEA), Task 34/43: Testing and validation of building energy simulation tools experts group....

Modelling, experimentation and simulation of a reversible HP/ORC unit to get a Positive Energy Building

DEFF Research Database (Denmark)

Dumont, Olivier; Carmo, Carolina; Quoilin, Sylvain

2015-01-01

This paper presents an innovative building comprising a heat pump connected to a solar roof and a geothermal heat exchanger. This unit is able to invert its cycle and operate as an Organic Rankine Cycle (ORC). The solar roof is producing large amount of heat throughout the year. This allows...... and fluid R134a shows promising performance with a net electrical energy produced over one year reaching 4030 kWh. Following that, a prototype has been built and has proven the feasibility of the technology. Finally, a simulation code including the building, the ground heat exchanger, the thermal energy...... storage, the solar roof and the reversible HP/ORC unit is developed and allows to perform a sensivity analysis. Annual results show that this technology leads to a Positive Energy Building....

Optimizing Existing Multistory Building Designs towards Net-Zero Energy

Directory of Open Access Journals (Sweden)

Mohammad Y. AbuGrain

2017-03-01

Full Text Available Recent global developments in awareness and concerns about environmental problems have led to reconsidering built environment approaches and construction techniques. One of the alternatives is the principle of low/zero-energy buildings. This study investigates the potentials of energy savings in an existing multi-story building in the Mediterranean region in order to achieve net-zero energy as a solution to increasing fossil fuel prices. The Colored building at the Faculty of Architecture, Eastern Mediterranean University, Cyprus was chosen as a target of this study to be investigated and analyzed in order to know how energy efficiency strategies could be applied to the building to reduce annual energy consumption. Since this research objective is to develop a strategy to achieve net-zero energy in existing buildings, case study and problem solving methodologies were applied in this research in order to evaluate the building design in a qualitative manner through observations, in addition to a quantitative method through an energy modeling simulation to achieve desirable results which address the problems. After optimizing the building energy performance, an alternative energy simulation was made of the building in order to make an energy comparison analysis, which leads to reliable conclusions. These methodologies and the strategies used in this research can be applied to similar buildings in order to achieve net-zero energy goals.

Net-zero Building Cluster Simulations and On-line Energy Forecasting for Adaptive and Real-Time Control and Decisions

Science.gov (United States)

Li, Xiwang

Buildings consume about 41.1% of primary energy and 74% of the electricity in the U.S. Moreover, it is estimated by the National Energy Technology Laboratory that more than 1/4 of the 713 GW of U.S. electricity demand in 2010 could be dispatchable if only buildings could respond to that dispatch through advanced building energy control and operation strategies and smart grid infrastructure. In this study, it is envisioned that neighboring buildings will have the tendency to form a cluster, an open cyber-physical system to exploit the economic opportunities provided by a smart grid, distributed power generation, and storage devices. Through optimized demand management, these building clusters will then reduce overall primary energy consumption and peak time electricity consumption, and be more resilient to power disruptions. Therefore, this project seeks to develop a Net-zero building cluster simulation testbed and high fidelity energy forecasting models for adaptive and real-time control and decision making strategy development that can be used in a Net-zero building cluster. The following research activities are summarized in this thesis: 1) Development of a building cluster emulator for building cluster control and operation strategy assessment. 2) Development of a novel building energy forecasting methodology using active system identification and data fusion techniques. In this methodology, a systematic approach for building energy system characteristic evaluation, system excitation and model adaptation is included. The developed methodology is compared with other literature-reported building energy forecasting methods; 3) Development of the high fidelity on-line building cluster energy forecasting models, which includes energy forecasting models for buildings, PV panels, batteries and ice tank thermal storage systems 4) Small scale real building validation study to verify the performance of the developed building energy forecasting methodology. The outcomes of

2014 Building America House Simulation Protocols

Energy Technology Data Exchange (ETDEWEB)

Wilson, E. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Engebrecht, C. Metzger [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Horowitz, S. [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Hendron, R. [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

2014-03-01

As Building America has grown to include a large and diverse cross-section of the home building and retrofit industries, it has become more important to develop accurate, consistent analysis techniques to measure progress towards the program's goals. The House Simulation Protocol (HSP) document provides guidance to program partners and managers so they can compare energy savings for new construction and retrofit projects. The HSP provides the program with analysis methods that are proven to be effective and reliable in investigating the energy use of advanced energy systems and of entire houses.

Simulation-based support for integrated design of new low-energy office buildings

DEFF Research Database (Denmark)

Petersen, Steffen

. The method uses the energy frame concept to express the constraints of the optimisation problem, which is then solved by minimising the costs of conserving energy in all the individual energy-saving measures. A case example illustrates how the method enables designers to establish a qualified estimate...... a method for making informed decisions in the early stages of building design to fulfil performance requirements with regard to energy consumption and indoor environment. The method is operationalised in a program that utilises a simple simulation program to make performance predictions of user......-defined parameter variations. The program then presents the output in a way that enables designers to make informed decisions. The method and the program reduce the need for design iterations, reducing time consumption and construction costs, to obtain the intended energy performance and indoor environment. Paper...

Simulation of energy use in buildings with multiple micro generators

International Nuclear Information System (INIS)

Karmacharya, S.; Putrus, G.; Underwood, C.P.; Mahkamov, K.; McDonald, S.; Alexakis, A.

2014-01-01

This paper focuses on the detailed modelling of micro combined heat and power (mCHP) modules and their interaction with other renewable micro generators in domestic applications based on an integrated modular modelling approach. The simulation model has been developed using Matlab/Simulink and incorporates a Stirling engine mCHP module embedded in a lumped-parameter domestic energy model, together with contributions from micro wind and photovoltaic modules. The Stirling cycle component model is based on experimental identification of a domestic-scale system which includes start up and shut down characteristics. The integrated model is used to explore the interactions between the various energy supply technologies and results are presented showing the most favourable operating conditions that can be used to inform the design of advanced energy control strategies in building. The integrated model offers an improvement on previous models of this kind in that a fully-dynamic approach is adopted for the equipment and plant enabling fast changing load events such as switching on/off domestic loads and hot water, to be accurately captured at a minimum interval of 1 min. The model is applied to two typical 3- and 4-bedroom UK house types equipped with a mCHP module and two other renewable energy technologies for a whole year. Results of the two cases show that the electrical contribution of a Stirling engine type mCHP heavily depends on the thermal demand of the building and that up to 19% of the locally-generated electricity is exported whilst meeting a similar percentage of the overall annual electricity demand. Results also show that the increased number of switching of mCHP module has an impact on seasonal module efficiency and overall fuel utilisation. The results demonstrate the need for the analysis of equipment design and optimal sizing of thermal and electrical energy storage. -- Highlights: • Dynamic modelling of a building along with its space heating and hot

Building Energy Consumption Pattern Analysis of Detached Housing for the Policy Decision Simulator

Science.gov (United States)

Lim, Jiyoun; Lee, Seung-Eon

2018-03-01

The Korean government announced its plan to raise the previous reduction goal of greenhouse gas emission from buildings by 26.9% until 2020 on July 2015. Therefore, policies regarding efficiency in the building energy are implemented fast, but the level of building owners and market understanding is low in general, and the government service system which supports decision making for implementing low-energy buildings has not been provided yet. The purpose of this study is to present the design direction for establishing user customized building energy database to perform a role to provide autonomous ecosystem of low-energy buildings. In order to reduce energy consumption in buildings, it is necessary to carry out the energy performance analysis based on the characteristics of target building. By analysing about 20-thousand cases of the amount of housing energy consumption in Korea, this study suggested the real energy consumption pattern by building types. Also, the energy performance of a building could be determined by energy consumption, but previous building energy consumption analysis programs required expert knowledge and experience in program usage, so it was difficult for normal building users to use such programs. Therefore, a measure to provide proper default using the level of data which general users with no expert knowledge regarding building energy could enter easily was suggested in this study.

Estimating building energy consumption using extreme learning machine method

International Nuclear Information System (INIS)

Naji, Sareh; Keivani, Afram; Shamshirband, Shahaboddin; Alengaram, U. Johnson; Jumaat, Mohd Zamin; Mansor, Zulkefli; Lee, Malrey

2016-01-01

The current energy requirements of buildings comprise a large percentage of the total energy consumed around the world. The demand of energy, as well as the construction materials used in buildings, are becoming increasingly problematic for the earth's sustainable future, and thus have led to alarming concern. The energy efficiency of buildings can be improved, and in order to do so, their operational energy usage should be estimated early in the design phase, so that buildings are as sustainable as possible. An early energy estimate can greatly help architects and engineers create sustainable structures. This study proposes a novel method to estimate building energy consumption based on the ELM (Extreme Learning Machine) method. This method is applied to building material thicknesses and their thermal insulation capability (K-value). For this purpose up to 180 simulations are carried out for different material thicknesses and insulation properties, using the EnergyPlus software application. The estimation and prediction obtained by the ELM model are compared with GP (genetic programming) and ANNs (artificial neural network) models for accuracy. The simulation results indicate that an improvement in predictive accuracy is achievable with the ELM approach in comparison with GP and ANN. - Highlights: • Buildings consume huge amounts of energy for operation. • Envelope materials and insulation influence building energy consumption. • Extreme learning machine is used to estimate energy usage of a sample building. • The key effective factors in this study are insulation thickness and K-value.

Early decision support for net zero energy buildings design using building performance simulation

NARCIS (Netherlands)

Attia, S.G.; Gratia, E.; De Herde, A.; Hensen, J.L.M.

2013-01-01

This paper aims to investigate the use of building performance simulation tools as a method of informing the design decision of NZEBs. The aim of this study is to evaluate the effect of a simulation-based decision aid, ZEBO, on informed decision-making using sensitivity analysis. The objective is to

A technical framework to describe occupant behavior for building energy simulations

Energy Technology Data Exchange (ETDEWEB)

Turner, William; Hong, Tianzhen

2013-12-20

Green buildings that fail to meet expected design performance criteria indicate that technology alone does not guarantee high performance. Human influences are quite often simplified and ignored in the design, construction, and operation of buildings. Energy-conscious human behavior has been demonstrated to be a significant positive factor for improving the indoor environment while reducing the energy use of buildings. In our study we developed a new technical framework to describe energy-related human behavior in buildings. The energy-related behavior includes accounting for individuals and groups of occupants and their interactions with building energy services systems, appliances and facilities. The technical framework consists of four key components: i. the drivers behind energy-related occupant behavior, which are biological, societal, environmental, physical, and economical in nature ii. the needs of the occupants are based on satisfying criteria that are either physical (e.g. thermal, visual and acoustic comfort) or non-physical (e.g. entertainment, privacy, and social reward) iii. the actions that building occupants perform when their needs are not fulfilled iv. the systems with which an occupant can interact to satisfy their needs The technical framework aims to provide a standardized description of a complete set of human energy-related behaviors in the form of an XML schema. For each type of behavior (e.g., occupants opening/closing windows, switching on/off lights etc.) we identify a set of common behaviors based on a literature review, survey data, and our own field study and analysis. Stochastic models are adopted or developed for each type of behavior to enable the evaluation of the impact of human behavior on energy use in buildings, during either the design or operation phase. We will also demonstrate the use of the technical framework in assessing the impact of occupancy behavior on energy saving technologies. The technical framework presented is

Building performance simulation for sustainable buildings

NARCIS (Netherlands)

Hensen, J.L.M.

2010-01-01

This paper aims to provide a general view of the background and current state of building performance simulation, which has the potential to deliver, directly or indirectly, substantial benefits to building stakeholders and to the environment. However the building simulation community faces many

Building energy efficiency in different climates

International Nuclear Information System (INIS)

Lam, Joseph C.; Wan, Kevin K.W.; Tsang, C.L.; Yang Liu

2008-01-01

Energy simulation was conducted for office buildings in the five major climate zones - severe cold, cold, hot summer and cold winter, mild, and hot summer and warm winter - in China using DOE-2.1E. The primary aim was to investigate the thermal and energy performance of office buildings with centralised heating, ventilation and air conditioning plants in the major climatic zones in China. The computed results were analysed in three aspects - heating load, cooling load and the corresponding building energy consumption. The building peak monthly heating load varied from 142 MW h (1033 MW h cooling) in Hong Kong to 447 MW h (832 MW h cooling) in Harbin. It was also found that passive solar designs could have large energy savings potential in the severe cold and cold climates. In Harbin, the window solar component helped lower the annual building heating load by 650 MW h. Internal loads (lighting and office equipment) and part load operations of fans and pumps also played a significant role in the overall building energy efficiency. This paper presents the work, its findings and energy efficiency implications

Validation Methodology to Allow Simulated Peak Reduction and Energy Performance Analysis of Residential Building Envelope with Phase Change Materials: Preprint

Energy Technology Data Exchange (ETDEWEB)

Tabares-Velasco, P. C.; Christensen, C.; Bianchi, M.

2012-08-01

Phase change materials (PCM) represent a potential technology to reduce peak loads and HVAC energy consumption in residential buildings. This paper summarizes NREL efforts to obtain accurate energy simulations when PCMs are modeled in residential buildings: the overall methodology to verify and validate Conduction Finite Difference (CondFD) and PCM algorithms in EnergyPlus is presented in this study. It also shows preliminary results of three residential building enclosure technologies containing PCM: PCM-enhanced insulation, PCM impregnated drywall and thin PCM layers. The results are compared based on predicted peak reduction and energy savings using two algorithms in EnergyPlus: the PCM and Conduction Finite Difference (CondFD) algorithms.

EVALUATION OF ENERGY PERFORMANCE USING DOE-2 ENERGY SIMULATION PROGRAM IN SINGAPORE

Directory of Open Access Journals (Sweden)

Po Seng Kian

2000-01-01

Full Text Available Recently, due to worldwide energy cost rising significantly, there has been an essential need to minimize the energy consumption. This global warning address many countries including Singapore realizing the important of energy efficiency in industries and buildings. This paper deals with analyzing the energy consumption of an 11-storey commercial building in Singapore using DOE-2 Energy Simulation Program. A study is made on the benefits derived from modifying the building envelope, space system setting, air-conditioning plant, and lighting. This encompasses a description of its quantitative impact on cooling load, energy consumption and energy saving achieved as compared with the original building. Following this, a life cycle costing is done to determine the economic benefits attained from this modification. This study shows that some alternative solutions can be achieved using energy simulation program to conserve the energy consumption.

Translating building information modeling to building energy modeling using model view definition.

Science.gov (United States)

Jeong, WoonSeong; Kim, Jong Bum; Clayton, Mark J; Haberl, Jeff S; Yan, Wei

2014-01-01

This paper presents a new approach to translate between Building Information Modeling (BIM) and Building Energy Modeling (BEM) that uses Modelica, an object-oriented declarative, equation-based simulation environment. The approach (BIM2BEM) has been developed using a data modeling method to enable seamless model translations of building geometry, materials, and topology. Using data modeling, we created a Model View Definition (MVD) consisting of a process model and a class diagram. The process model demonstrates object-mapping between BIM and Modelica-based BEM (ModelicaBEM) and facilitates the definition of required information during model translations. The class diagram represents the information and object relationships to produce a class package intermediate between the BIM and BEM. The implementation of the intermediate class package enables system interface (Revit2Modelica) development for automatic BIM data translation into ModelicaBEM. In order to demonstrate and validate our approach, simulation result comparisons have been conducted via three test cases using (1) the BIM-based Modelica models generated from Revit2Modelica and (2) BEM models manually created using LBNL Modelica Buildings library. Our implementation shows that BIM2BEM (1) enables BIM models to be translated into ModelicaBEM models, (2) enables system interface development based on the MVD for thermal simulation, and (3) facilitates the reuse of original BIM data into building energy simulation without an import/export process.

Translating Building Information Modeling to Building Energy Modeling Using Model View Definition

Directory of Open Access Journals (Sweden)

WoonSeong Jeong

2014-01-01

Full Text Available This paper presents a new approach to translate between Building Information Modeling (BIM and Building Energy Modeling (BEM that uses Modelica, an object-oriented declarative, equation-based simulation environment. The approach (BIM2BEM has been developed using a data modeling method to enable seamless model translations of building geometry, materials, and topology. Using data modeling, we created a Model View Definition (MVD consisting of a process model and a class diagram. The process model demonstrates object-mapping between BIM and Modelica-based BEM (ModelicaBEM and facilitates the definition of required information during model translations. The class diagram represents the information and object relationships to produce a class package intermediate between the BIM and BEM. The implementation of the intermediate class package enables system interface (Revit2Modelica development for automatic BIM data translation into ModelicaBEM. In order to demonstrate and validate our approach, simulation result comparisons have been conducted via three test cases using (1 the BIM-based Modelica models generated from Revit2Modelica and (2 BEM models manually created using LBNL Modelica Buildings library. Our implementation shows that BIM2BEM (1 enables BIM models to be translated into ModelicaBEM models, (2 enables system interface development based on the MVD for thermal simulation, and (3 facilitates the reuse of original BIM data into building energy simulation without an import/export process.

Energy Signal Tool for Decision Support in Building Energy Systems

Energy Technology Data Exchange (ETDEWEB)

Henze, G. P.; Pavlak, G. S.; Florita, A. R.; Dodier, R. H.; Hirsch, A. I.

2014-12-01

A prototype energy signal tool is demonstrated for operational whole-building and system-level energy use evaluation. The purpose of the tool is to give a summary of building energy use which allows a building operator to quickly distinguish normal and abnormal energy use. Toward that end, energy use status is displayed as a traffic light, which is a visual metaphor for energy use that is either substantially different from expected (red and yellow lights) or approximately the same as expected (green light). Which light to display for a given energy end use is determined by comparing expected to actual energy use. As expected, energy use is necessarily uncertain; we cannot choose the appropriate light with certainty. Instead, the energy signal tool chooses the light by minimizing the expected cost of displaying the wrong light. The expected energy use is represented by a probability distribution. Energy use is modeled by a low-order lumped parameter model. Uncertainty in energy use is quantified by a Monte Carlo exploration of the influence of model parameters on energy use. Distributions over model parameters are updated over time via Bayes' theorem. The simulation study was devised to assess whole-building energy signal accuracy in the presence of uncertainty and faults at the submetered level, which may lead to tradeoffs at the whole-building level that are not detectable without submetering.

Simulation of energy use, human thermal comfort and office work performance in buildings with moderately drifting operative temperatures

DEFF Research Database (Denmark)

Kolarik, Jakub; Toftum, Jørn; Olesen, Bjarne W.

2011-01-01

Annual primary energy use in a central module of an office building consisting of two offices separated with a corridor was estimated by means of dynamic computer simulations. The simulations were conducted for conventional all-air VAV ventilation system and thermo active building system (TABS) s....... The TABS working in a moderate climate kept the predicted percentage of dissatisfied (PPD) 10%; 1.4% in comparison to 17.5% h/yr. The highest estimated loss of occupants’ productivity related to their thermal sensation hasn’t exceeded 1% in whole year average....

Analysis of Energy Demand for Low-Energy Multi-Dwelling Buildings of Different Configuration

Directory of Open Access Journals (Sweden)

Giedrė Streckienė

2014-10-01

Full Text Available To meet the goals established by Directive 2010/31/EU of the European Parliament and of the Council on the energy performance of buildings, the topics of energy efficiency in new and old buildings must be solved. Research and development of new energy solutions and technology are necessary for increasing energy performance of buildings. Three low-energy multi-dwelling buildings have been modelled and analyzed in the presented study. All multi-dwelling houses are made of similar single-family house cells. However, multi-dwelling buildings are of different geometry, flat number and height. DesignBuilder software was used for simulating and determining heating, cooling and electricity demand for buildings. Three different materials (silicate, ceramic and clay concrete blocks as bearing constructions of external walls have been analyzed. To decrease cooling demand for buildings, the possibility of mounting internal or external louvers has been considered. Primary energy savings for multi-dwelling buildings using passive solar measures have been determined.

Co-simulation of innovative integrated HVAC systems in buildings

Energy Technology Data Exchange (ETDEWEB)

Trcka, Marija; Hensena, Jan L.M.; Wetter, Michael

2010-06-21

Integrated performance simulation of buildings HVAC systems can help in reducing energy consumption and increasing occupant comfort. However, no single building performance simulation (BPS) tool offers sufficient capabilities and flexibilities to analyze integrated building systems and to enable rapid prototyping of innovative building and system technologies. One way to alleviate this problem is to use co-simulation, as an integrated approach to simulation. This article elaborates on issues important for co-simulation realization and discusses multiple possibilities to justify the particular approach implemented in the here described co-simulation prototype. The prototype is validated with the results obtained from the traditional simulation approach. It is further used in a proof-of-concept case study to demonstrate the applicability of the method and to highlight its benefits. Stability and accuracy of different coupling strategies are analyzed to give a guideline for the required coupling time step.

Method for simulating predictive control of building systems operation in the early stages of building design

DEFF Research Database (Denmark)

Petersen, Steffen; Svendsen, Svend

2011-01-01

A method for simulating predictive control of building systems operation in the early stages of building design is presented. The method uses building simulation based on weather forecasts to predict whether there is a future heating or cooling requirement. This information enables the thermal...... control systems of the building to respond proactively to keep the operational temperature within the thermal comfort range with the minimum use of energy. The method is implemented in an existing building simulation tool designed to inform decisions in the early stages of building design through...... parametric analysis. This enables building designers to predict the performance of the method and include it as a part of the solution space. The method furthermore facilitates the task of configuring appropriate building systems control schemes in the tool, and it eliminates time consuming manual...

Eawag Forum Chriesbach - Simulation and measurement of energy performance and comfort in a sustainable office building

Energy Technology Data Exchange (ETDEWEB)

Lehmann, B.; Dorer, V.; Frank, Th. [Empa, Swiss Federal Laboratories for Materials Science and Technology, Laboratory for Building Science and Technology, Ueberlandstrasse 129, CH-8600 Duebendorf (Switzerland); Guettinger, H. [Eawag, Swiss Federal Institute of Aquatic Science and Technology, Duebendorf (Switzerland); van Velsen, S.; Thiemann, A. [3-Plan Haustechnik AG, Winterthur (Switzerland)

2010-10-15

The Eawag's new headquarters ''Forum Chriesbach'' is an exemplary illustration of a 'sustainable' construction design for office buildings. With a unique combination of architectural and technical elements the building reaches a very low 88 kWh/m{sup 2} overall primary energy consumption, which is significantly lower than the Swiss Passive House standard, Minergie-P. A monitoring and evaluation project shows that the building is heated mainly by using the sun and internal heat gains from lighting, electrical appliances and occupants, resulting in an extremely low space heating demand. Cooling is provided by natural night time ventilation and the earth-coupled air intake, which pre-cools supply air and provides free cooling for computer servers. However, values for embodied energy and electricity consumption remain significant, even with partial on-site electricity production using photovoltaics. TRNSYS computer simulations show the contributions of individual building services to the overall energy balance and indicate that the building is resilient towards changes in parameters such as climate or occupancy density. Measurements confirm comfortable room temperatures below 26 C, even during an extremely hot summer period, and 20-23 C in the winter season. An economic analysis reveals additional costs of only 5% compared to a conventionally constructed building and a payback-time of 13 years. (author)

Design and optimization of zero-energy-consumption based solar energy residential building systems

Science.gov (United States)

Zheng, D. L.; Yu, L. J.; Tan, H. W.

2017-11-01

Energy consumption of residential buildings has grown fast in recent years, thus raising a challenge on zero energy residential building (ZERB) systems, which aim at substantially reducing energy consumption of residential buildings. Thus, how to facilitate ZERB has become a hot but difficult topic. In the paper, we put forward the overall design principle of ZERB based on analysis of the systems’ energy demand. In particular, the architecture for both schematic design and passive technology is optimized and both energy simulation analysis and energy balancing analysis are implemented, followed by committing the selection of high-efficiency appliance and renewable energy sources for ZERB residential building. In addition, Chinese classical residential building has been investigated in the proposed case, in which several critical aspects such as building optimization, passive design, PV panel and HVAC system integrated with solar water heater, Phase change materials, natural ventilation, etc., have been taken into consideration.

Expand the Modeling Capabilities of DOE's EnergyPlus Building Energy Simulation Program

Energy Technology Data Exchange (ETDEWEB)

Don Shirey

2008-02-28

EnergyPlus{trademark} is a new generation computer software analysis tool that has been developed, tested, and commercialized to support DOE's Building Technologies (BT) Program in terms of whole-building, component, and systems R&D (http://www.energyplus.gov). It is also being used to support evaluation and decision making of zero energy building (ZEB) energy efficiency and supply technologies during new building design and existing building retrofits. Version 1.0 of EnergyPlus was released in April 2001, followed by semiannual updated versions over the ensuing seven-year period. This report summarizes work performed by the University of Central Florida's Florida Solar Energy Center (UCF/FSEC) to expand the modeling capabilities of EnergyPlus. The project tasks involved implementing, testing, and documenting the following new features or enhancement of existing features: (1) A model for packaged terminal heat pumps; (2) A model for gas engine-driven heat pumps with waste heat recovery; (3) Proper modeling of window screens; (4) Integrating and streamlining EnergyPlus air flow modeling capabilities; (5) Comfort-based controls for cooling and heating systems; and (6) An improved model for microturbine power generation with heat recovery. UCF/FSEC located existing mathematical models or generated new model for these features and incorporated them into EnergyPlus. The existing or new models were (re)written using Fortran 90/95 programming language and were integrated within EnergyPlus in accordance with the EnergyPlus Programming Standard and Module Developer's Guide. Each model/feature was thoroughly tested and identified errors were repaired. Upon completion of each model implementation, the existing EnergyPlus documentation (e.g., Input Output Reference and Engineering Document) was updated with information describing the new or enhanced feature. Reference data sets were generated for several of the features to aid program users in selecting proper

Energy Benchmarking in Educational Buildings through Cluster Analysis of Energy Retrofitting

Directory of Open Access Journals (Sweden)

Paola Marrone

2018-03-01

Full Text Available A large part of the stock of Italian educational buildings have undertaken energy retrofit interventions, thanks to European funds allocated by complex technical-administrative calls. In these projects, the suggested retrofit strategies are often selected based on the common best practices (considering average energy savings but are not supported by proper energy investigations. In this paper, Italian school buildings’ stock was analyzed by cluster analysis with the aim of providing a methodology able to identify the best energy retrofit interventions from the perspective of cost-benefit, and to correlate them with the specific characteristics of the educational buildings. This research is based on the analysis of about 80 school buildings located in central Italy and characterized by different features and construction technologies. The refurbished buildings were classified in homogeneous clusters and, for each of them, the most representative building was identified. Furthermore, for each representative building a validating procedure based on dynamic simulations and a comparison with actual energy use was performed. The two buildings thus singled out provide a model that could be developed into a useful tool for Public Administrations to suggest priorities in the planning of new energy retrofits of existing school building stocks.

Energy Modelling and Automated Calibrations of Ancient Building Simulations: A Case Study of a School in the Northwest of Spain

Directory of Open Access Journals (Sweden)

Ana Ogando

2017-06-01

Full Text Available In the present paper, the energy performance of buildings forming a school centre in the northwest of Spain was analyzed using a transient simulation of the energy model of the school, which was developed with TRNSYS, a software of proven reliability in the field of thermal simulations. A deterministic calibration approach was applied to the initial building model to adjust the predictions to the actual performance of the school, data acquired during the temperature measurement campaign. The buildings under study were in deteriorated conditions due to poor maintenance over the years, presenting a big challenge for modelling and simulating it in a reliable way. The results showed that the proposed methodology is successful for obtaining calibrated thermal models of these types of damaged buildings, as the metrics employed to verify the final error showed a reduced normalized mean bias error (NMBE of 2.73%. It was verified that a decrease of approximately 60% in NMBE and 17% in the coefficient of variation of the root mean square error (CV(RMSE was achieved due to the calibration process. Subsequent steps were performed with the aid of new software, which was developed under a European project that enabled the automated calibration of the simulations.

Optimising building net energy demand with dynamic BIPV shading

International Nuclear Information System (INIS)

Jayathissa, P.; Luzzatto, M.; Schmidli, J.; Hofer, J.; Nagy, Z.; Schlueter, A.

2017-01-01

Highlights: •Coupled analysis of PV generation and building energy using adaptive BIPV shading. •20–80% net energy saving compared to an equivalent static system. •The system can in some cases compensate for the entire heating/cooling/lighting load. •High resolution radiation simulation including impacts of module self shading. -- Abstract: The utilisation of a dynamic photovoltaic system for adaptive shading can improve building energy performance by controlling solar heat gains and natural lighting, while simultaneously generating electricity on site. This paper firstly presents an integrated simulation framework to couple photovoltaic electricity generation to building energy savings through adaptive shading. A high-resolution radiance and photovoltaic model calculates the photovoltaic electricity yield while taking into account partial shading between modules. The remaining solar irradiation that penetrates the window is used in a resistance-capacitance building thermal model. A simulation of all possible dynamic configurations is conducted for each hourly time step, of which the most energy efficient configuration is chosen. We then utilise this framework to determine the optimal orientation of the photovoltaic panels to maximise the electricity generation while minimising the building’s heating, lighting and cooling demand. An existing adaptive photovoltaic facade was used as a case study for evaluation. Our results report a 20–80% net energy saving compared to an equivalent static photovoltaic shading system depending on the efficiency of the heating and cooling system. In some cases the Adaptive Solar Facade can almost compensate for the entire energy demand of the office space behind it. The control of photovoltaic production on the facade, simultaneously with the building energy demand, opens up new methods of building management as the facade can control both the production and consumption of electricity.

A generalized window energy rating system for typical office buildings

Energy Technology Data Exchange (ETDEWEB)

Tian, Cheng; Chen, Tingyao; Yang, Hongxing; Chung, Tse-ming [Research Center for Building Environmental Engineering, Department of Building Services Engineering, The Hong Kong Polytechnic University, Hong Kong (China)

2010-07-15

Detailed computer simulation programs require lengthy inputs, and cannot directly provide an insight to relationship between the window energy performance and the key window design parameters. Hence, several window energy rating systems (WERS) for residential houses and small buildings have been developed in different countries. Many studies showed that utilization of daylight through elaborate design and operation of windows leads to significant energy savings in both cooling and lighting in office buildings. However, the current WERSs do not consider daylighting effect, while most of daylighting analyses do not take into account the influence of convective and infiltration heat gains. Therefore, a generalized WERS for typical office buildings has been presented, which takes all primary influence factors into account. The model includes embodied and operation energy uses and savings by a window to fully reflect interactions among the influence parameters. Reference locations selected for artificial lighting and glare control in the current common simulation practice may cause uncompromised conflicts, which could result in over- or under-estimated energy performance. Widely used computer programs, DOE2 and ADELINE, for hourly daylighting and cooling simulations have their own weaknesses, which may result in unrealistic or inaccurate results. An approach is also presented for taking the advantages of the both programs and avoiding their weaknesses. The model and approach have been applied to a typical office building of Hong Kong as an example to demonstrate how a WERS in a particular location can be established and how well the model can work. The energy effect of window properties, window-to-wall ratio (WWR), building orientation and lighting control strategies have been analyzed, and can be indicated by the localized WERS. An application example also demonstrates that the algebraic WERS derived from simulation results can be easily used for the optimal design of

Energy Performance Certification of Faculty Buildings in Spain: The gap between estimated and real energy consumption

International Nuclear Information System (INIS)

Herrando, María; Cambra, David; Navarro, Marcos; Cruz, Lucio de la; Millán, Gema; Zabalza, Ignacio

2016-01-01

Highlights: • Most of the Faculty Buildings studied are within the average of CO_2 emissions. • Academic and Research buildings have a similar simulated energy consumption. • Several restrictions found in the official Energy Performance Certification tool. • Average deviation of 30% between estimated and real energy consumption. • Electrical equipment and user behaviour notably increase the energy performance gap. - Abstract: A systematic method has been established to perform and analyse in detail the Energy Performance Certification of 21 Faculty Buildings located at the University of Zaragoza (Spain), according to the transposition of Directive 2010/31/EU. First of all, the problem background and a review of the state-of-the-art of the energy certification in buildings is outlined, regarding both the actual state of the Government regulations and the studies undertaken in several countries to assess the energy performance of different types of buildings, residential and non-residential. A summary of the causes found in other studies for the discrepancies between the estimated (by simulation) and actual energy consumption is shown which is afterwards tested and compared with the results found in the present study. Thereafter, the method followed to undertake the buildings’ Energy Performance Certification is explained, and the main results found together with the discussion are detailed, comparing actual vs. estimated energy consumption in the different case studies and proposing reasons for these deviations. The energy consumption breakdown by uses for several buildings is also analysed, and potential improvements for the simulation software are assessed.

Thermal mass impact on energy performance of a low, medium and heavy mass building in Belgrade

Directory of Open Access Journals (Sweden)

Anđelković Bojan V.

2012-01-01

Full Text Available Heavy mass materials used in building structures and architecture can significantly affect building energy performance and occupant comfort. The purpose of this study was to investigate if thermal mass can improve the internal environment of a building, resulting in lower energy requirements from the mechanical systems. The study was focused on passive building energy performance and compared annual space heating and cooling energy requirements for an office building in Belgrade with several different applications of thermal mass. A three-dimensional building model was generated to represent a typical office building. Building shape, orientation, glazing to wall ratio, envelope insulation thickness, and indoor design conditions were held constant while location and thickness of building mass (concrete was varied between cases in a series of energy simulations. The results were compared and discussed in terms of the building space heating and cooling energy and demand affected by thermal mass. The simulation results indicated that with addition of thermal mass to the building envelope and structure: 100% of all simulated cases experienced reduced annual space heating energy requirements, 67% of all simulated cases experienced reduced annual space cooling energy requirements, 83% of all simulated cases experienced reduced peak space heating demand and 50% of all simulated cases experienced reduced peak space cooling demand. The study demonstrated that there exists a potential for reducing space heating and cooling energy requirements with heavy mass construction in the analyzed climate region (Belgrade, Serbia.

A meta model-based methodology for an energy savings uncertainty assessment of building retrofitting

Directory of Open Access Journals (Sweden)

Caucheteux Antoine

2016-01-01

Full Text Available To reduce greenhouse gas emissions, energy retrofitting of building stock presents significant potential for energy savings. In the design stage, energy savings are usually assessed through Building Energy Simulation (BES. The main difficulty is to first assess the energy efficiency of the existing buildings, in other words, to calibrate the model. As calibration is an under determined problem, there is many solutions for building representation in simulation tools. In this paper, a method is proposed to assess not only energy savings but also their uncertainty. Meta models, using experimental designs, are used to identify many acceptable calibrations: sets of parameters that provide the most accurate representation of the building are retained to calculate energy savings. The method was applied on an existing office building modeled with the TRNsys BES. The meta model, using 13 parameters, is built with no more than 105 simulations. The evaluation of the meta model on thousands of new simulations gives a normalized mean bias error between the meta model and BES of <4%. Energy savings are assessed based on six energy savings concepts, which indicate savings of 2–45% with a standard deviation ranging between 1.3% and 2.5%.

Energy Performance and CO2 Emissions of HVAC Systems in Commercial Buildings

Directory of Open Access Journals (Sweden)

Rafat Al-Waked

2017-10-01

Full Text Available Energy performance of buildings has attracted much attention among building physicists and engineers worldwide. The effects of building heating; ventilation; and air conditioning (HVAC systems’ design upgrade on the building energy performance are the focus of the current study. The adopted HVAC system consisted of chilled ceiling and chilled beam systems served by a centrifugal water chiller. An energy simulation study was undertaken in accordance with the national Australian built environment rating system-rules for collecting and using data. A three-dimensional simulation study was carried out utilizing the virtual environment-integrated environmental solutions software. Results from the current study have shown the importance of utilizing energy-efficient HVAC systems and HVAC strategies for achieving a high building energy star rating. Recommended strategies in order to achieve the nominated star rating; as predicted by the simulation analysis; were presented. Moreover; the effects of solar radiation inside the building atrium were significant; which cannot be overcome by simply installing a low shading coefficient glazing type at the atrium skylight. In addition to providing chilled ceiling technology; a high efficiency chiller and low energy lighting; it is recommended that the building be well tuned during the commissioning period. The current approach could be extended to accommodate higher energy ratings of commercial buildings at different locations worldwide.

Calculation steps. Building integrated energy supply; Beregningsgang. Bygningsintegreret energiforsyning

Energy Technology Data Exchange (ETDEWEB)

Jensen, Rasmus L.; Noergaard, J.; Daniels, O.; Justesen, R.O.

2011-08-15

In the future, buildings will not only act as consumers of energy but as producers as well. For these ''prosumers'', energy production by use of solar panels, photovoltaics and heat pumps etc will be essential. The objective of this project was to find the most optimal combinations of building insulation and use of renewable energy sources in existing buildings in terms of economics and climate impacts. Five houses were analyzed based on different personal load, consumption profiles, solar orientation and proposed building envelope improvements and use of combinations of renewable energy systems. The analysis was conducted by making a large number of simulations. The present report describes the applied simulation models, and explains the results and computer codes. The parameter variations are described for each house as well as the common calculation steps for each house. The results are presented in case sheets, as performance graphs, and top-50 lists for the best cases regarding CO{sub 2} emission, energy consumption and economics. (ln)

Building concepts for a transition towards energy neutrality in 2050

Energy Technology Data Exchange (ETDEWEB)

De Boer, B.J.; Paauw, J. [TNO Built Environment and Geosciences, Delft (Netherlands); Opstelten, I.J.; Bakker, E.J. [Energy research Centre of the Netherlands ECN, Petten (Netherlands)

2007-03-15

In this paper building concepts for the near future are described which enable the transition towards a net energy neutral building sector in the Netherlands by the year 2050. With 'net energy neutrality' is meant that, on a yearly basis, the total energy consumption in the built environment is compensated by local renewable energy production e.g. by using solar thermal (T), photovoltaic (PV), PVT and/or wind. A study concerning the feasibility of a 'net energy neutral built environment by 2050' set the energetic ambitions for the building concepts to be developed. This resulted in different concepts for residential buildings and for office-buildings. The building concepts are based on passive house technology to minimise the heating and cooling demand, and make optimal use of active and passive solar energy. Concepts for new to build domestic buildings are in fact energy producing to compensate for the remaining energy demand of existing, renovated dwellings. In all concepts the 'trias energetica' or 'energy pyramid' served as a general guideline, striving for minimisation of energy demand, maximal usage of renewable energy and usage of fossil fuels as efficiently as possible. Different full roof integrated options for using solar energy (PV, T or PVT) with variable storage options have been compared by making simulations with a dynamic simulation programme, to gain insight on their impact on energy, building engineering and economic impact. Also different possibilities for installations to fulfil the heating demand for the space heating and DHW demand are compared. For each concept, the resulting primary energy profiles for space heating and cooling, domestic hot water, electricity consumption for lighting, ventilation and household appliances are given.

Energy Performance Indicators in the Swedish Building Procurement Process

Directory of Open Access Journals (Sweden)

Ingrid Allard

2017-10-01

Full Text Available In Sweden, all new buildings need to comply with the National Board of Housing, Building and Planning’s requirement on specific purchased energy (kWh/m2. Accordingly, this indicator is often used to set design criteria in the building procurement process. However, when energy use is measured in finished buildings, the measurements often deviate significantly from the design calculations. The measured specific purchased energy does not necessarily reflect the responsibility of the building contractor, as it is influenced by the building operation, user behavior and climate. Therefore, Swedish building practitioners may prefer other indicators for setting design criteria in the building procurement process. The aim of this study was twofold: (i to understand the Swedish building practitioners’ perspectives and opinions on seven building energy performance indicators (envelope air leakage, U-values for different building parts, average U-value, specific heat loss, heat loss coefficient, specific net energy, and specific purchased energy; and (ii to understand the consequences for the energy performance of multi-family buildings of using the studied indicators to set criteria in the procurement process. The study involved a Delphi approach and simulations of a multi-family case study building. The studied indicators were discussed in terms of how they may meet the needs of the building practitioners when used to set building energy performance criteria in the procurement process.

Building energy analysis tool

Science.gov (United States)

Brackney, Larry; Parker, Andrew; Long, Nicholas; Metzger, Ian; Dean, Jesse; Lisell, Lars

2016-04-12

A building energy analysis system includes a building component library configured to store a plurality of building components, a modeling tool configured to access the building component library and create a building model of a building under analysis using building spatial data and using selected building components of the plurality of building components stored in the building component library, a building analysis engine configured to operate the building model and generate a baseline energy model of the building under analysis and further configured to apply one or more energy conservation measures to the baseline energy model in order to generate one or more corresponding optimized energy models, and a recommendation tool configured to assess the one or more optimized energy models against the baseline energy model and generate recommendations for substitute building components or modifications.

Building energy modeling for green architecture and intelligent dashboard applications

Science.gov (United States)

DeBlois, Justin

Buildings are responsible for 40% of the carbon emissions in the United States. Energy efficiency in this sector is key to reducing overall greenhouse gas emissions. This work studied the passive technique called the roof solar chimney for reducing the cooling load in homes architecturally. Three models of the chimney were created: a zonal building energy model, computational fluid dynamics model, and numerical analytic model. The study estimated the error introduced to the building energy model (BEM) through key assumptions, and then used a sensitivity analysis to examine the impact on the model outputs. The conclusion was that the error in the building energy model is small enough to use it for building simulation reliably. Further studies simulated the roof solar chimney in a whole building, integrated into one side of the roof. Comparisons were made between high and low efficiency constructions, and three ventilation strategies. The results showed that in four US climates, the roof solar chimney results in significant cooling load energy savings of up to 90%. After developing this new method for the small scale representation of a passive architecture technique in BEM, the study expanded the scope to address a fundamental issue in modeling - the implementation of the uncertainty from and improvement of occupant behavior. This is believed to be one of the weakest links in both accurate modeling and proper, energy efficient building operation. A calibrated model of the Mascaro Center for Sustainable Innovation's LEED Gold, 3,400 m2 building was created. Then algorithms were developed for integration to the building's dashboard application that show the occupant the energy savings for a variety of behaviors in real time. An approach using neural networks to act on real-time building automation system data was found to be the most accurate and efficient way to predict the current energy savings for each scenario. A stochastic study examined the impact of the

Simulation-Based Multiobjective Optimization of Timber-Glass Residential Buildings in Severe Cold Regions

Directory of Open Access Journals (Sweden)

Yunsong Han

2017-12-01

Full Text Available In the current context of increasing energy demand, timber-glass buildings will become a necessary trend in sustainable architecture in the future. Especially in severe cold zones of China, energy consumption and the visual comfort of residential buildings have attracted wide attention, and there are always trade-offs between multiple objectives. This paper aims to propose a simulation-based multiobjective optimization method to improve the daylighting, energy efficiency, and economic performance of timber-glass buildings in severe cold regions. Timber-glass building form variables have been selected as the decision variables, including building width, roof height, south and north window-to-wall ratio (WWR, window height, and orientation. A simulation-based multiobjective optimization model has been developed to optimize these performance objectives simultaneously. The results show that Daylighting Autonomy (DA presents negative correlations with Energy Use Intensity (EUI and total cost. Additionally, with an increase in DA, Useful Daylighting Illuminance (UDI demonstrates a tendency of primary increase and then decrease. Using this optimization model, four building performances have been improved from the initial generation to the final generation, which proves that simulation-based multiobjective optimization is a promising approach to improve the daylighting, energy efficiency, and economic performances of timber-glass buildings in severe cold regions.

A Fuzzy-Based Building Energy Management System for Energy Efficiency

Directory of Open Access Journals (Sweden)

José L. Hernández

2018-01-01

Full Text Available Information and communication technologies (ICT offer immense potential to improve the energetic performance of buildings. Additionally, common building control systems are typically based on simple decision-making tools, which possess the ability to obtain controllable parameters for indoor temperatures. Nevertheless, the accuracy of such common building control systems is improvable with the integration of advanced decision-making techniques embedded into software and energy management tools. This paper presents the design of a building energy management system (BEMS, which is currently under development, and that makes use of artificial intelligence for the automated decision-making process required for optimal comfort of occupants and utilization of renewables for achieving energy-efficiency in buildings. The research falls under the scope of the H2020 project BREASER which implements fuzzy logic with the aim of governing the energy resources of a school in Turkey, which has been renovated with a ventilated façade with integrated renewable energy sources (RES. The BRESAER BEMS includes prediction techniques that increase the accuracy of common BEMS tools, and subsequent energy savings, while ensuring the indoor thermal comfort of the building occupants. In particular, weather forecast and simulation strategies are integrated into the functionalities of the overall system. By collecting the aforementioned information, the BEMS makes decisions according to a well-established selection of key performance indicators (KPIs with the objective of providing a quantitative comparable value to determine new actuation parameters.

Guidelines for Using Building Information Modeling for Energy Analysis of Buildings

Directory of Open Access Journals (Sweden)

Thomas Reeves

2015-12-01

Full Text Available Building energy modeling (BEM, a subset of building information modeling (BIM, integrates energy analysis into the design, construction, and operation and maintenance of buildings. As there are various existing BEM tools available, there is a need to evaluate the utility of these tools in various phases of the building lifecycle. The goal of this research was to develop guidelines for evaluation and selection of BEM tools to be used in particular building lifecycle phases. The objectives of this research were to: (1 Evaluate existing BEM tools; (2 Illustrate the application of the three BEM tools; (3 Re-evaluate the three BEM tools; and (4 Develop guidelines for evaluation, selection and application of BEM tools in the design, construction and operation/maintenance phases of buildings. Twelve BEM tools were initially evaluated using four criteria: interoperability, usability, available inputs, and available outputs. Each of the top three BEM tools selected based on this initial evaluation was used in a case study to simulate and evaluate energy usage, daylighting performance, and natural ventilation for two academic buildings (LEED-certified and non-LEED-certified. The results of the case study were used to re-evaluate the three BEM tools using the initial criteria with addition of the two new criteria (speed and accuracy, and to develop guidelines for evaluating and selecting BEM tools to analyze building energy performance. The major contribution of this research is the development of these guidelines that can help potential BEM users to identify the most appropriate BEM tool for application in particular building lifecycle phases.

Performance analysis of an energy efficient building prototype by using TRNSYS

OpenAIRE

Lai, Kun; Wang, Wen; Giles, Harry

2014-01-01

Buildings section accouts for a large part of the total primary energy consumption. This paper reports a simulative study on an energy efficient building prototype named MIDMOD by using TRNSYS program. The prototype is a new genre of affordable medium density building concepts that are more adaptable, durable, and energy efficient as whole-life housing typologies than those currently available.The building envelope thermal insulation and air tightness are enhanced to reduce heat loss. Several...

Evaluation of Automated Model Calibration Techniques for Residential Building Energy Simulation

Energy Technology Data Exchange (ETDEWEB)

and Ben Polly, Joseph Robertson [National Renewable Energy Lab. (NREL), Golden, CO (United States); Polly, Ben [National Renewable Energy Lab. (NREL), Golden, CO (United States); Collis, Jon [Colorado School of Mines, Golden, CO (United States)

2013-09-01

This simulation study adapts and applies the general framework described in BESTEST-EX (Judkoff et al 2010) for self-testing residential building energy model calibration methods. BEopt/DOE-2.2 is used to evaluate four mathematical calibration methods in the context of monthly, daily, and hourly synthetic utility data for a 1960's-era existing home in a cooling-dominated climate. The home's model inputs are assigned probability distributions representing uncertainty ranges, random selections are made from the uncertainty ranges to define "explicit" input values, and synthetic utility billing data are generated using the explicit input values. The four calibration methods evaluated in this study are: an ASHRAE 1051-RP-based approach (Reddy and Maor 2006), a simplified simulated annealing optimization approach, a regression metamodeling optimization approach, and a simple output ratio calibration approach. The calibration methods are evaluated for monthly, daily, and hourly cases; various retrofit measures are applied to the calibrated models and the methods are evaluated based on the accuracy of predicted savings, computational cost, repeatability, automation, and ease of implementation.

Evaluation of Automated Model Calibration Techniques for Residential Building Energy Simulation

Energy Technology Data Exchange (ETDEWEB)

Robertson, J.; Polly, B.; Collis, J.

2013-09-01

This simulation study adapts and applies the general framework described in BESTEST-EX (Judkoff et al 2010) for self-testing residential building energy model calibration methods. BEopt/DOE-2.2 is used to evaluate four mathematical calibration methods in the context of monthly, daily, and hourly synthetic utility data for a 1960's-era existing home in a cooling-dominated climate. The home's model inputs are assigned probability distributions representing uncertainty ranges, random selections are made from the uncertainty ranges to define 'explicit' input values, and synthetic utility billing data are generated using the explicit input values. The four calibration methods evaluated in this study are: an ASHRAE 1051-RP-based approach (Reddy and Maor 2006), a simplified simulated annealing optimization approach, a regression metamodeling optimization approach, and a simple output ratio calibration approach. The calibration methods are evaluated for monthly, daily, and hourly cases; various retrofit measures are applied to the calibrated models and the methods are evaluated based on the accuracy of predicted savings, computational cost, repeatability, automation, and ease of implementation.

Uncertainty and sensitivity analysis in building performance simulation for decision support and design optimization

NARCIS (Netherlands)

Hopfe, C.J.

2009-01-01

Building performance simulation (BPS) uses computer-based models that cover performance aspects such as energy consumption and thermal comfort in buildings. The uptake of BPS in current building design projects is limited. Although there is a large number of building simulation tools available, the

Addendum to the Building America House Simulation Protocols

Energy Technology Data Exchange (ETDEWEB)

Engebrecht-Metzger, C.; Wilson, E.; Horowitz, S.

2012-12-01

As Building America (BA) has grown to include a large and diverse cross-section of the home building and retrofit industries, it has become more important to develop accurate, consistent analysis techniques to measure progress towards the program's goals. The House Simulation Protocols (HSP) provides guidance to program partners and managers so that energy savings for new construction and retrofit projects can be compared alongside each other. The HSP provides the program with analysis methods that are proven to be effective and reliable in investigating the energy use of advanced energy systems and of entire houses.

Addendum to the Building America House Simulation Protocols

Energy Technology Data Exchange (ETDEWEB)

Engebrecht, C. Metzger [National Renewable Energy Lab. (NREL), Golden, CO (United States); Wilson, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Horowitz, S. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2012-12-01

As DOE's Building America program has grown to include a large and diverse cross-section of the home building and retrofit industries, it has become more important to develop accurate, consistent analysis techniques to measure progress towards the program’s goals. The House Simulation Protocols (HSP) provide guidance to program partners and managers so that energy savings for new construction and retrofit projects can be compared alongside each other. The HSP provides the program with analysis methods that are proven to be effective and reliable in investigating the energy use of advanced energy systems and of entire houses.

Impact of coupled heat and moisture transfer effects on buildings energy consuption

Directory of Open Access Journals (Sweden)

Ferroukhi Mohammed Yacine

2017-01-01

Full Text Available Coupled heat, air, and moisture transfers through building envelope have an important effect on prediction of building energy requirements. Several works were conducted in order to integrate hygrothermal transfers in dynamic buildings simulations codes. However, the incorporation of multidirectional hygrothermal transfer analysis in the envelope into building simulation tools is rarely considered. In this work, coupled heat, air, and moisture (HAM transfer model in multilayer walls was established. Thereafter, the HAM model is coupled dynamically to a building behavior code (BES.The coupling concerns a co-simulation between COMSOL Multiphysics and TRNSYS software. Afterward, the HAM-BES co-simulation accuracy was verified. Then, HAM-BES co-simulation platform was applied to a case study with various types of climates (temperate, hot and humid, cold and humid. Three simulations cases were carried out. The first simulation case consists of the TRNSYS model without HAM transfer model. The second simulation case, 1-D HAM model for the envelope was integrated in TRNSYS code. For the third one, 1-D HAM model for the wall and 2-D HAM model for thermal bridges were coupled to the thermal building model of TRNSYS. Analysis of the results confirms the significant impact of 2-D envelope hygrothermal transfers on the indoor thermal and moisture behavior of building as well as on the energy building assessment. These conclusions are shown for different studied climates.

Results. Building integrated energy supply; Resultater. Bygningsintegreret energiforsyning

Energy Technology Data Exchange (ETDEWEB)

Jensen, Rasmus L.; Noergaard, J.; Daniels, O.; Justesen, R.O.

2011-08-15

In the future, buildings will not only act as consumers of energy but as producers as well. For these ''prosumers'', energy production by use of solar panels, photovoltaics and heat pumps etc will be essential. The objective of this project was to find the most optimal combinations of building insulation and use of renewable energy sources in existing buildings in terms of economics and climate impacts. Five houses were analyzed based on different personal load, consumption profiles, solar orientation and proposed building envelope improvements and use of combinations of renewable energy systems. The analysis was conducted by making a large number of simulations of which the best combinations were selected. The final result takes form of a single top-50 list with the best combinations of energy systems according to CO{sub 2} emission, energy consumption and economics. The present report contains the conclusions of and comments on the project's results. (ln)

Virtual Design Studio (VDS) - Development of an Integrated Computer Simulation Environment for Performance Based Design of Very-Low Energy and High IEQ Buildings

Energy Technology Data Exchange (ETDEWEB)

Chen, Yixing [Building Energy and Environmental Systems Lab. (BEESL), Syracuse, NY (United States); Zhang, Jianshun [Syracuse Univ., NY (United States); Pelken, Michael [Syracuse Univ., NY (United States); Gu, Lixing [Univ. of Central Florida, Orlando, FL (United States); Rice, Danial [Building Energy and Environmental Systems Lab. (BEESL), Syracuse, NY (United States); Meng, Zhaozhou [Building Energy and Environmental Systems Lab. (BEESL), Syracuse, NY (United States); Semahegn, Shewangizaw [Building Energy and Environmental Systems Lab. (BEESL), Syracuse, NY (United States); Feng, Wei [Building Energy and Environmental Systems Lab. (BEESL), Syracuse, NY (United States); Ling, Francesca [Syracuse Univ., NY (United States); Shi, Jun [Building Energy and Environmental Systems Lab. (BEESL), Syracuse, NY (United States); Henderson, Hugh [CDH Energy, Cazenovia, NY (United States)

2013-09-01

Executive Summary The objective of this study was to develop a “Virtual Design Studio (VDS)”: a software platform for integrated, coordinated and optimized design of green building systems with low energy consumption, high indoor environmental quality (IEQ), and high level of sustainability. This VDS is intended to assist collaborating architects, engineers and project management team members throughout from the early phases to the detailed building design stages. It can be used to plan design tasks and workflow, and evaluate the potential impacts of various green building strategies on the building performance by using the state of the art simulation tools as well as industrial/professional standards and guidelines for green building system design. Engaged in the development of VDS was a multi-disciplinary research team that included architects, engineers, and software developers. Based on the review and analysis of how existing professional practices in building systems design operate, particularly those used in the U.S., Germany and UK, a generic process for performance-based building design, construction and operation was proposed. It distinguishes the whole process into five distinct stages: Assess, Define, Design, Apply, and Monitoring (ADDAM). The current VDS is focused on the first three stages. The VDS considers building design as a multi-dimensional process, involving multiple design teams, design factors, and design stages. The intersection among these three dimensions defines a specific design task in terms of “who”, “what” and “when”. It also considers building design as a multi-objective process that aims to enhance the five aspects of performance for green building systems: site sustainability, materials and resource efficiency, water utilization efficiency, energy efficiency and impacts to the atmospheric environment, and IEQ. The current VDS development has been limited to energy efficiency and IEQ performance, with particular focus

Sensitivity analysis for daily building operation from the energy and thermal comfort standpoint

Directory of Open Access Journals (Sweden)

Ignjatović Marko G.

2016-01-01

Full Text Available Improving energy performance of buildings is one of the most important tasks for reaching sustainability. Assessing building energy consumption is performed more often with specialized simulation tools. Sensitivity analysis proved to be a valuable tool for creating more reliable and realistic building energy models and better buildings. This paper briefly describes the methodology for running global sensitivity analysis and tools that can be used, and presents the results of such an analysis conducted for winter period, daily, on input variables covering a real building's operation, control and occupant related parameters that affect both thermal comfort and heating energy consumption. Two sets of inputs were created. The only difference between these sets is an addition of clothing insulation and occupant heat gain as input variables. The reference building was simulated for three distinctive winter weeks. Two additional input variables have an effect especially on thermal comfort, but they do not disturb the relative order of other influential input variables. The common influential variables for both energy consumption and thermal comfort were identified and are: air handling unit sup-ply temperature and airflow rate and control system related parameters. This can help in future research into implementing the simulation-assisted optimized operation in real buildings. [Projekat Ministarstva nauke Republike Srbije, br. TR-33051: The concept of sustainable energy supply of settlements with energy efficient buildings

Building simulations supporting decision making in early design – A review

DEFF Research Database (Denmark)

Østergård, Torben; Jensen, Rasmus Lund; Maagaard, Steffen

2016-01-01

The building design community is challenged by continuously increasing energy demands, which are often combined with ambitious goals for indoor environment, for environmental impact, and for building costs. To aid decision-making, building simulation is widely used in the late design stages...... framework that facilitates proactive, intelligent, and experience based building simulation which aid decision making in early design. To find software candidates accommodating this framework, we compare existing software with regard to intended usage, interoperability, complexity, objectives, and ability...

NET-ZERO ENERGY BUILDING OPERATOR TRAINING PROGRAM (NZEBOT)

Energy Technology Data Exchange (ETDEWEB)

Brizendine, Anthony; Byars, Nan; Sleiti, Ahmad; Gehrig, Bruce; Lu, Na

2012-12-31

topics in the primary five-day Building Energy/Sustainability Management Certificate program in five training modules, namely: 1) Strategic Planning, 2) Sustainability Audits, 3) Information Analysis, 4) Energy Efficiency, and 5) Communication. Training Program 2 addresses the following technical topics in the two-day Building Technologies workshop: 1) Energy Efficient Building Materials, 2) Green Roofing Systems, 3) Energy Efficient Lighting Systems, 4) Alternative Power Systems for Buildings, 5) Innovative Building Systems, and 6) Application of Building Performance Simulation Software. Program 3 is a seminar which provides an overview of elements of programs 1 and 2 in a seminar style presentation designed for the general public to raise overall public awareness of energy and sustainability topics.

Investigation of building energy autonomy in the sahelian environment

International Nuclear Information System (INIS)

Coulibaly, O; Koulidiati, J; Ouedraogo, A; Kuznik, F; Baillis, D

2012-01-01

In this study, the energy generation of a set of photovoltaic panels is compared with the energy load of a building in order to analyse its autonomy in the sahelian environment when taking into account, the orientation, the insulation and the energy transfer optimisation of its windows. The Type 56 TRNSYS multizone building model is utilized for the energy load simulation and the Type 94 model of the same code enables the coupling of photovoltaic (PV) panels with the building. Without insulation, the PV energy generation represents 73.52 and 111.79% of the building electric energy load, respectively for poly-crystalline and mono-crystalline panels. For the same PV characteristics and when we insulate the roof and the floor, the energy generation increases to represent successively 121.09 and 184.13%. In the meantime, for building without insulation and with insulate the roof, the floor and 2 cm insulated walls, the energy consumption ratios decrease respectively from 201.13 to 105.20 kWh/m 2 /year. The investigations finally show that it is even possible to generate excess energy (positive energy building) and reduce the number and incident surface area of the PV panels if we conjugate the previous model with building passive architectural design mode (orientation, solar protection ...).

Technical Support Document: Development of the Advanced Energy Design Guide for Small Office Buildings

Energy Technology Data Exchange (ETDEWEB)

Jarnagin, Ronald E.; Liu, Bing; Winiarski, David W.; McBride, Merle F.; Suharli, L.; Walden, D.

2006-11-30

This Technical Support Document (TSD) describes the process and methodology for the development of the Advanced Energy Design Guide for Small Office Buildings (AEDG-SO), a design guidance document intended to provide recommendations for achieving 30% energy savings in small office buildings over levels contained in ANSI/ASHRAE/IESNA Standard 90.1-1999, Energy Standard for Buildings Except Low-Rise Residential Buildings. The AEDG-SO is the first in a series of guides being developed by a partnership of organizations, including the American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc. (ASHRAE), the American Institute of Architects (AIA), the Illuminating Engineering Society of North America (IESNA), the New Buildings Institute (NBI), and the U.S. Department of Energy (DOE). Each of the guides in the AEDG series will provide recommendations and user-friendly design assistance to designers, developers and owners of small commercial buildings that will encourage steady progress towards net-zero energy buildings. The guides will provide prescriptive recommendation packages that are capable of reaching the energy savings target for each climate zone in order to ease the burden of the design and construction of energy-efficient small commercial buildings The AEDG-SO was developed by an ASHRAE Special Project committee (SP-102) made up of representatives of each of the partner organizations in eight months. This TSD describes the charge given to the committee in developing the office guide and outlines the schedule of the development effort. The project committee developed two prototype office buildings (5,000 ft2 frame building and 20,000 ft2 two-story mass building) to represent the class of small office buildings and performed an energy simulation scoping study to determine the preliminary levels of efficiency necessary to meet the energy savings target. The simulation approach used by the project committee is documented in this TSD along with

Study on simulation methods of atrium building cooling load in hot and humid regions

Energy Technology Data Exchange (ETDEWEB)

Pan, Yiqun; Li, Yuming; Huang, Zhizhong [Institute of Building Performance and Technology, Sino-German College of Applied Sciences, Tongji University, 1239 Siping Road, Shanghai 200092 (China); Wu, Gang [Weldtech Technology (Shanghai) Co. Ltd. (China)

2010-10-15

In recent years, highly glazed atria are popular because of their architectural aesthetics and advantage of introducing daylight into inside. However, cooling load estimation of such atrium buildings is difficult due to complex thermal phenomena that occur in the atrium space. The study aims to find out a simplified method of estimating cooling loads through simulations for various types of atria in hot and humid regions. Atrium buildings are divided into different types. For every type of atrium buildings, both CFD and energy models are developed. A standard method versus the simplified one is proposed to simulate cooling load of atria in EnergyPlus based on different room air temperature patterns as a result from CFD simulation. It incorporates CFD results as input into non-dimensional height room air models in EnergyPlus, and the simulation results are defined as a baseline model in order to compare with the results from the simplified method for every category of atrium buildings. In order to further validate the simplified method an actual atrium office building is tested on site in a typical summer day and measured results are compared with simulation results using the simplified methods. Finally, appropriate methods of simulating different types of atrium buildings are proposed. (author)

Moisture buffering phenomenon and its impact on building energy consumption

DEFF Research Database (Denmark)

Zhang, Mingjie; Qin, Menghao; Rode, Carsten

2017-01-01

buffering on building energy consumption in different climate conditions is assessed by using numerical simulations. The results show that the potential energy saving rate could be up to 25–30% when using proper hygroscopic materials in the test building in temperate climates and semi-arid climates. Finally......, the relationship between MBV and potential energy saving rate is also discussed....

Dynamic energy performance analysis: Case study for energy efficiency retrofits of hospital buildings

International Nuclear Information System (INIS)

Buonomano, Annamaria; Calise, Francesco; Ferruzzi, Gabriele; Palombo, Adolfo

2014-01-01

This paper investigates several actions for the energy refurbishment of some buildings of the University Hospital Federico II of Naples. The analysis focuses on a specific lot of 4 buildings, representative of the whole district hospital. For those structures, sustainable energy savings actions are investigated. They regard the installation of: i) roofs thermal insulation; ii) a substation climatic 3-way valve; iii) radiators thermostatic valves; iv) AHU (air handling unit) time-programmable regulation. This paper aims at presenting an investigation methodology, useful for designers and other stakeholders involved in hospital energy refurbishments, based on an integrated approach which combines dynamic energy performance simulations and experimental campaigns. In order to measure all the simulations' missing input parameters, a suitable experimental analysis, including measurements of temperature, humidity, flow rate and density of construction materials, is performed. A thermographic investigation is also performed for investigating the building envelope performance. This analysis showed that significant savings can be achieved especially by adopting radiators thermostatic valves and AHU regulations. Coherently, the installation of a 3-way valve in the substation does not determine significant additional savings when radiators thermostatic valves are already installed. For high-rise buildings, roofs insulation returns only marginal reductions of space heating and cooling demands. - Highlights: • Energy saving measures applied to the largest hospital of South Italy are analyzed. • A new approach combining dynamic simulations and measurements is implemented. • Thermography, temperature and flow measurements are performed. • High savings are achieved by adopting thermostatic valves and AHU control systems. • The simplest energy saving actions resulted to be the most profitable ones

2014 Building America House Simulation Protocols

Energy Technology Data Exchange (ETDEWEB)

Wilson, E. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Engebrecht-Metzger, C. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Horowitz, S. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Hendron, R. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2014-03-01

As BA has grown to include a large and diverse cross-section of the home building and retrofit industries, it has become more important to develop accurate, consistent analysis techniques to measure progress towards the program's goals. The House Simulation Protocol (HSP) document provides guidance to program partners and managers so they can compare energy savings for new construction and retrofit projects. The HSP provides the program with analysis methods that are proven to be effective and reliable in investigating the energy use of advanced energy systems and of entire houses.

Parametrisation of the variety of human behaviour related to building energy consumption in the Town Energy Balance (SURFEX-TEB v. 8.2

Directory of Open Access Journals (Sweden)

R. Schoetter

2017-07-01

Full Text Available The anthropogenic heat flux can be an important part of the urban surface energy balance. Some of it is due to energy consumption inside buildings, which depends on building use and human behaviour, both of which are very heterogeneous in most urban areas. Urban canopy parametrisations (UCP, such as the Town Energy Balance (TEB, parametrise the effect of the buildings on the urban surface energy balance. They contain a simple building energy model. However, the variety of building use and human behaviour at grid point scale has not yet been represented in state of the art UCPs. In this study, we describe how we enhance the Town Energy Balance in order to take fractional building use and human behaviour into account. We describe how we parametrise different behaviours and initialise the model for applications in France. We evaluate the spatio-temporal variability of the simulated building energy consumption for the city of Toulouse. We show that a more detailed description of building use and human behaviour enhances the simulation results. The model developments lay the groundwork for simulations of coupled urban climate and building energy consumption which are relevant for both the urban climate and the climate change mitigation and adaptation communities.

Parametrisation of the variety of human behaviour related to building energy consumption in the Town Energy Balance (SURFEX-TEB v. 8.2)

Science.gov (United States)

Schoetter, Robert; Masson, Valéry; Bourgeois, Alexis; Pellegrino, Margot; Lévy, Jean-Pierre

2017-07-01

The anthropogenic heat flux can be an important part of the urban surface energy balance. Some of it is due to energy consumption inside buildings, which depends on building use and human behaviour, both of which are very heterogeneous in most urban areas. Urban canopy parametrisations (UCP), such as the Town Energy Balance (TEB), parametrise the effect of the buildings on the urban surface energy balance. They contain a simple building energy model. However, the variety of building use and human behaviour at grid point scale has not yet been represented in state of the art UCPs. In this study, we describe how we enhance the Town Energy Balance in order to take fractional building use and human behaviour into account. We describe how we parametrise different behaviours and initialise the model for applications in France. We evaluate the spatio-temporal variability of the simulated building energy consumption for the city of Toulouse. We show that a more detailed description of building use and human behaviour enhances the simulation results. The model developments lay the groundwork for simulations of coupled urban climate and building energy consumption which are relevant for both the urban climate and the climate change mitigation and adaptation communities.

Energy and behavioral impacts of integrative retrofits for residential buildings: What is at stake for building energy policy reforms in northern China?

International Nuclear Information System (INIS)

Xu, Peng; Xu, Tengfang; Shen, Pengyuan

2013-01-01

Based upon the results from extensive building monitoring and surveys on occupant’s behaviors in a representative nine-story apartment building in northern China, building energy simulations were performed to evaluate the impacts of integrative retrofits implemented. Integrative retrofits required by the newer building energy standard produced significant heating-energy savings (i.e., 53%) when compared with baseline buildings commonly built in early 1980s. Taking into account district-heating-system upgrades as part of integrative retrofit measures, a representative apartment building was 66% more efficient than the baseline building. Contrary to expectation, little behavioral change was found in response to the provisions of monetary incentive, billing-method reform, or metering of heating energy use in individual apartment units. Yet this paper identified sizable energy savings potential if occupants’ behavioral changes were to actually happen. This indicates that provisions of financial incentives or individual metering were insufficient for triggering substantial behavioral changes leading toward more energy savings in the current buildings. It is recommended that innovative energy policies, technology upgrades, and education would be needed to promote behavioral changes toward additional energy savings. Finally, measures and strategies to further enhance thermal integrity criteria (e.g., insulations of roof and balcony) are recommended in China’s future building energy policy reforms. - Highlights: ► Integrative retrofits significantly reduce residential heating energy in north China. ► Energy effects of retrofits, incentive, billing and behavioral changes were studied. ► Monetary incentive, control or metering technologies did not lead to behavior change. ► Potential energy savings due to occupants’ behavioral changes are sizable. ► Thermal integrity needs to be enhanced in future building standards and policies.

Energy optimization of office buildings; Energioptimering af kontorbyggeri

Energy Technology Data Exchange (ETDEWEB)

Wittchen, K.B.; Place Hansen, E.J. de (Statens Byggeforskningsinstitut (SBi), Hoersholm (Denmark)); Radisch, N.H.; Treldal, J. (Ramboell A/S, Koebenhavn (Denmark))

2011-07-01

The project analysed two main office building types - high-rises and low-rises - and calculated a number of parameters, using the simulation program BSim. Calculations showed that the overall building design and orientation effect is moderate compared with, for instance, use of daylight control and low-energy lighting, computers, etc. Considerable energy savings can be achieved by use of natural ventilation in the summer, thus only using mechanical ventilation with heat recovery during the day in the winter. Open-plan offices result in a better indoor climate and lower energy consumption than cubicle offices. (LN)

Distributed dynamic simulations of networked control and building performance applications.

Science.gov (United States)

Yahiaoui, Azzedine

2018-02-01

The use of computer-based automation and control systems for smart sustainable buildings, often so-called Automated Buildings (ABs), has become an effective way to automatically control, optimize, and supervise a wide range of building performance applications over a network while achieving the minimum energy consumption possible, and in doing so generally refers to Building Automation and Control Systems (BACS) architecture. Instead of costly and time-consuming experiments, this paper focuses on using distributed dynamic simulations to analyze the real-time performance of network-based building control systems in ABs and improve the functions of the BACS technology. The paper also presents the development and design of a distributed dynamic simulation environment with the capability of representing the BACS architecture in simulation by run-time coupling two or more different software tools over a network. The application and capability of this new dynamic simulation environment are demonstrated by an experimental design in this paper.

Improving building energy efficiency in India: State-level analysis of building energy efficiency policies

Energy Technology Data Exchange (ETDEWEB)

Yu, Sha; Tan, Qing; Evans, Meredydd; Kyle, Page; Vu, Linh; Patel, Pralit L.

2017-11-01

India is expected to add 40 billion m2 of new buildings till 2050. Buildings are responsible for one third of India’s total energy consumption today and building energy use is expected to continue growing driven by rapid income and population growth. The implementation of the Energy Conservation Building Code (ECBC) is one of the measures to improve building energy efficiency. Using the Global Change Assessment Model, this study assesses growth in the buildings sector and impacts of building energy policies in Gujarat, which would help the state adopt ECBC and expand building energy efficiency programs. Without building energy policies, building energy use in Gujarat would grow by 15 times in commercial buildings and 4 times in urban residential buildings between 2010 and 2050. ECBC improves energy efficiency in commercial buildings and could reduce building electricity use in Gujarat by 20% in 2050, compared to the no policy scenario. Having energy codes for both commercial and residential buildings could result in additional 10% savings in electricity use. To achieve these intended savings, it is critical to build capacity and institution for robust code implementation.

Modeling and optimization of energy generation and storage systems for thermal conditioning of buildings targeting conceptual building design

Energy Technology Data Exchange (ETDEWEB)

Grahovac, Milica

2012-11-29

The thermal conditioning systems are responsible for almost half of the energy consump-tion by commercial buildings. In many European countries and in the USA, buildings account for around 40% of primary energy consumption and it is therefore vital to explore further ways to reduce the HVAC (Heating, Ventilation and Air Conditioning) system energy consumption. This thesis investigates the relationship between the energy genera-tion and storage systems for thermal conditioning of buildings (shorter: primary HVAC systems) and the conceptual building design. Certain building design decisions irreversibly influence a building's energy performance and, conversely, many generation and storage components impose restrictions on building design and, by their nature, cannot be introduced at a later design stage. The objective is, firstly, to develop a method to quantify this influence, in terms of primary HVAC system dimensions, its cost, emissions and energy consumption and, secondly, to enable the use of the developed method by architects during the conceptual design. In order to account for the non-stationary effects of the intermittent renewable energy sources (RES), thermal storage and for the component part load efficiencies, a time domain system simulation is required. An abstract system simulation method is proposed based on seven pre-configured primary HVAC system models, including components such as boil-ers, chillers and cooling towers, thermal storage, solar thermal collectors, and photovoltaic modules. A control strategy is developed for each of the models and their annual quasi-stationary simulation is performed. The performance profiles obtained are then used to calculate the energy consumption, carbon emissions and costs. The annuity method has been employed to calculate the cost. Optimization is used to automatically size the HVAC systems, based on their simulation performance. Its purpose is to identify the system component dimensions that provide

Modeling and optimization of energy generation and storage systems for thermal conditioning of buildings targeting conceptual building design

Energy Technology Data Exchange (ETDEWEB)

Grahovac, Milica

2012-11-29

The thermal conditioning systems are responsible for almost half of the energy consump-tion by commercial buildings. In many European countries and in the USA, buildings account for around 40% of primary energy consumption and it is therefore vital to explore further ways to reduce the HVAC (Heating, Ventilation and Air Conditioning) system energy consumption. This thesis investigates the relationship between the energy genera-tion and storage systems for thermal conditioning of buildings (shorter: primary HVAC systems) and the conceptual building design. Certain building design decisions irreversibly influence a building's energy performance and, conversely, many generation and storage components impose restrictions on building design and, by their nature, cannot be introduced at a later design stage. The objective is, firstly, to develop a method to quantify this influence, in terms of primary HVAC system dimensions, its cost, emissions and energy consumption and, secondly, to enable the use of the developed method by architects during the conceptual design. In order to account for the non-stationary effects of the intermittent renewable energy sources (RES), thermal storage and for the component part load efficiencies, a time domain system simulation is required. An abstract system simulation method is proposed based on seven pre-configured primary HVAC system models, including components such as boil-ers, chillers and cooling towers, thermal storage, solar thermal collectors, and photovoltaic modules. A control strategy is developed for each of the models and their annual quasi-stationary simulation is performed. The performance profiles obtained are then used to calculate the energy consumption, carbon emissions and costs. The annuity method has been employed to calculate the cost. Optimization is used to automatically size the HVAC systems, based on their simulation performance. Its purpose is to identify the system component dimensions that provide minimal

Multi-Criteria Analysis of Alternative Energy Supply Solutions to Public Nearly Zero Energy Buildings

Directory of Open Access Journals (Sweden)

Giedrius Šiupšinskas

2013-12-01

Full Text Available The article analyzes energy supply alternatives for modernised public nearly zero energy buildings. The paper examines alternative energy production systems such as heat pumps (air-water and ground-water, solar collectors, adsorption cooling, biomass boiler, solar photovoltaic, wind turbines and combinations of these systems. The simulation of the analysed building energy demand for different energy production alternatives has been performed using TRNSYS modelling software. In order to determine an optimal energy supply variant, the estimated results of energy, environmental, and economic evaluation have been converted into non-dimensional variables (3E using multi-criteria analysis.Article in Lithuanian

Evaluation of a energy consumption index for commercial buildings in Brazil

Energy Technology Data Exchange (ETDEWEB)

Silva, Jose Eduardo Correa Santana; Hernandez Neto, Alberto [Universidade de Sao Paulo (EP/USP), SP (Brazil). Escola Politecnica], Emails: jose.edu@gmail.com, ahneto@usp.br

2010-07-01

The present paper proposes a energy consumption index for commercial buildings located in four different Brazilian climates. For such evaluations, the building simulation tool EnergyPlus was used and a sensitivity analysis was made for some of the main parameters of an air-conditioned building. The analysis showed that the electrical power and lighting density as well as the COP of the air conditioning system promotes the higher variations on the proposed energy index. (author)

Analysis of variables that influence electric energy consumption in commercial buildings in Brazil

Energy Technology Data Exchange (ETDEWEB)

Carvalho, M.M.Q. [Technical Drawing Department, Fluminense Federal University, Niteroi, Rio de Janeiro (Brazil); Energy Planning Program, Alberto Luiz Coimbra Institute for Research and Graduate Studies in Engineering - COPPE, Federal University of Rio de Janeiro, Rio de Janeiro (Brazil); La Rovere, E.L. [Energy Planning Program, Alberto Luiz Coimbra Institute for Research and Graduate Studies in Engineering - COPPE, Federal University of Rio de Janeiro, Rio de Janeiro (Brazil); Goncalves, A.C.M. [Program for Graduate Studies in Architecture, School of Architecture and Urbanism, Federal University of Rio de Janeiro, Rio de Janeiro (Brazil)

2010-12-15

Air conditioning systems in commercial buildings in Brazil are responsible for about 70% share of their energy consumption. According to BEN 2009 (The Brazilian Energy Balance), energy consumption in the residential, commercial and public sectors, where most buildings are found, represents 9.3% of the final energy consumption in Brazil. This paper aims to examine design factors that could contribute to greater reductions of electric energy consumption in commercial buildings, with emphasis on air conditioning. Simulations were carried out using shades and different types of glass, walls, flooring and roofing. The VisualDOE 2.61 was used as a simulation tool for calculating energy consumption of the analyzed building. This paper shows that the energy performance of the building is considerably influenced by the facade protection and shows, through tables, the impact that decisions related to the top-level and facades have on the energy consumption of the building. The authors concluded that the results confirm the importance of taking energy use into account in the very first design stages of the project, since appropriate choices of types of glass, external shading and envelope materials have a significant impact on energy consumption. (author)

The perceived value of using BIM for energy simulation

Science.gov (United States)

Lewis, Anderson M.

Building Information Modeling (BIM) is becoming an increasingly important tool in the Architectural, Engineering & Construction (AEC) industries. Some of the benefits associated with BIM include but are not limited to cost and time savings through greater trade and design coordination, and more accurate estimating take-offs. BIM is a virtual 3D, parametric design software that allows users to store information of a model within and can be used as a communication platform between project stakeholders. Likewise, energy simulation is an integral tool for predicting and optimizing a building's performance during design. Creating energy models and running energy simulations can be a time consuming activity due to the large number of parameters and assumptions that must be addressed to achieve reasonably accurate results. However, leveraging information imbedded within Building Information Models (BIMs) has the potential to increase accuracy and reduce the amount of time required to run energy simulations and can facilitate continuous energy simulations throughout the design process, thus optimizing building performance. Although some literature exists on how design stakeholders perceive the benefits associated with leveraging BIM for energy simulation, little is known about how perceptions associated with leveraging BIM for energy simulation differ between various green design stakeholder user groups. Through an e-survey instrument, this study seeks to determine how perceptions of using BIMs to inform energy simulation differ among distinct design stakeholder groups, which include BIM-only users, energy simulation-only users and BIM and energy simulation users. Additionally, this study seeks to determine what design stakeholders perceive as the main barriers and benefits of implementing BIM-based energy simulation. Results from this study suggest that little to no correlation exists between green design stakeholders' perceptions of the value associated with using

Building performance simulation for sustainable building design and operation

NARCIS (Netherlands)

Hensen, J.L.M.

2011-01-01

This paper aims to provide a general view of the background and current state of building performance simulation, which has the potential to deliver, directly or indirectly, substantial benefits to building stakeholders and to the environment. However the building simulation community faces many

Comparison of co-simulation approaches for building and HVAC/R system simulation

NARCIS (Netherlands)

Trcka, M.; Wetter, M.; Hensen, J.L.M.; Jiang, Yi

2007-01-01

Appraisal of modern performance-based energy codes, as well as heating, ventilation, airconditioning and refrigeration (HVAC/R) system design require use of an integrated building and system performance simulation program. However, the required scope of the modeling library of such integrated tools

The effects of window alternatives on energy efficiency and building economy in high-rise residential buildings in moderate to humid climates

International Nuclear Information System (INIS)

Yaşar, Yalçın; Kalfa, Sibel Maçka

2012-01-01

Highlights: ► We investigated energy and economy efficiency of window alternatives in Trabzon. ► Energy consumptions of eight window alternatives were simulated and discussed. ► Window alternatives’s life cycle costs were calculated and compared. ► We suggested appropriate energy and economy efficient window alternatives. ► The study defines useful guidelines to select appropriate window alternatives. - Abstract: Currently, focused efforts are being made to determine the influence of windows on the energy consumption and economy of high-rise buildings. Certain window designs and appropriate glazing systems reduce building energy consumption for heating and cooling and contribute to building economy. This paper addresses double-glazed window units that are composed of tinted glass; clear reflective glass; low emissivity (low-e) glass; and smart glass (one surface consists of a high-performance, heat-reflective glass, and other surface has a low-emissivity coated). These materials reduce the heating and cooling loads of buildings by providing solar control and heat conservation. The aim of this study was to investigate the effects of these alternative units, rather than readily available double-glazed units, in two types of flats. The flats have the same construction and operating system, but they have different plan types with regard to building energy consumption and building economy as it relates to life cycle cost analysis. For this study, we selected buildings in Trabzon, in Climate Region II of Turkey, due to its moderate-humid climate. F- and C-type high-rise residential blocks, with flats composed of two to three bedrooms, constructed by the Republic of Turkey’s Prime Ministry Housing Development Administration of Turkey (TOKİ) are used as models for the simulation. The flat plans in these blocks are modeled using DesignBuilder v.1.8 energy simulation software. The simulation results show that smart-glazed units and those with low emissivity

Quantifying the potential of automated dynamic solar shading in office buildings through integrated simulations of energy and daylight

DEFF Research Database (Denmark)

Nielsen, Martin Vraa; Svendsen, Svend; Bjerregaard Jensen, Lotte

2011-01-01

The façade design is and should be considered a central issue in the design of energy-efficient buildings. That is why dynamic façade components are increasingly used to adapt to both internal and external impacts, and to cope with a reduction in energy consumption and an increase in occupant...... them with various window heights and orientations. Their performance was evaluated on the basis of the building’s total energy demand, its energy demand for heating, cooling and lighting, and also its daylight factors. Simulation results comparing the three façade alternatives show potential...

Performance evaluation of gas-power strategies for building energy conservation

International Nuclear Information System (INIS)

Gabbar, Hossam A.; Runge, Jason; Bondarenko, Daniel; Bower, Lowell; Pandya, Devarsh; Musharavati, Farayi; Pokharel, Shaligram

2015-01-01

Highlights: • Comparison of natural gas and hydrogen fuels for energy conservation in buildings. • Comparison between hydrogen and natural gas fuel cell is performed. • Simulations of building energy supply. • Performance evaluation of two potential gas-power supply scenarios in buildings. • Natural gas fuel cell showed better performance over hydrogen fuel cell. - Abstract: The work provided herein involves a comparison of natural gas and hydrogen fuels for the purpose of energy conservation for buildings via alternative energy generation methodologies. A case study simulation was developed for an average type of commercial building, a nine storey hotel located in Toronto. The two alternative energy source case studies involved the generation of hydrogen via the wind turbine for the fuel cell, and the use of natural gas directly in the steam reforming fuel cell. The simulations for both scenarios were run and the recorded results were compared to the original case study, as well as between the scenarios. To supply for the base load of the building the fuel cells were given the same kW rating for both scenarios. The identification of all existing technologies for hydrogen gas and natural gas has been carried out, and the similar technologies between the two gases were found. For the purpose of realism, only existing purchasable technologies were considered in this paper. Due to the lack of commercially available technologies for hydrogen gas, only a comparison of fuel cell systems could be accomplished. Over the course of the investigative work it was found that when there is no direct supply of hydrogen to the site of utilization, the natural gas fuel cell is beneficial to the building due to its greater efficiency and lower cost. The major drawback for the hydrogen gas fuel cell, when the on-site generation is involved, is that no thermal power extraction systems currently exist for purchase and utilization in the buildings

Zero Energy Building

DEFF Research Database (Denmark)

Marszal, Anna Joanna; Heiselberg, Per; Bourrelle, J.S.

2011-01-01

The concept of Zero Energy Building (ZEB) has gained wide international attention during last few years and is now seen as the future target for the design of buildings. However, before being fully implemented in the national building codes and international standards, the ZEB concept requires......, (4) the type of energy balance, (5) the accepted renewable energy supply options, (6) the connection to the energy infrastructure and (7) the requirements for the energy efficiency, the indoor climate and in case of gird connected ZEB for the building–grid interaction. This paper focuses...

Co-Simulation of Detailed Whole Building with the Power System to Study Smart Grid Applications

Energy Technology Data Exchange (ETDEWEB)

Makhmalbaf, Atefe; Fuller, Jason C.; Srivastava, Viraj; Ciraci, Selim; Daily, Jeffrey A.

2014-12-24

Modernization of the power system in a way that ensures a sustainable energy system is arguably one of the most pressing concerns of our time. Buildings are important components in the power system. First, they are the main consumers of electricity and secondly, they do not have constant energy demand. Conventionally, electricity has been difficult to store and should be consumed as it is generated. Therefore, maintaining the demand and supply is critical in the power system. However, to reduce the complexity of power models, buildings (i.e., end-use loads) are traditionally modeled and represented as aggregated “dumb” nodes in the power system. This means we lack effective detailed whole building energy models that can support requirements and emerging technologies of the smart power grid. To gain greater insight into the relationship between building energy demand and power system performance, it is important to constitute a co-simulation framework to support detailed building energy modeling and simulation within the power system to study capabilities promised by the modern power grid. This paper discusses ongoing work at Pacific Northwest National Laboratory and presents underlying tools and framework needed to enable co-simulation of building, building energy systems and their control in the power system to study applications such as demand response, grid-based HVAC control, and deployment of buildings for ancillary services. The optimal goal is to develop an integrated modeling and simulation platform that is flexible, reusable, and scalable. Results of this work will contribute to future building and power system studies, especially those related to the integrated ‘smart grid’. Results are also expected to advance power resiliency and local (micro) scale grid studies where several building and renewable energy systems transact energy directly. This paper also reviews some applications that can be supported and studied using the framework introduced

The Brazilian energy crisis and a study to support building efficiency legislation

Energy Technology Data Exchange (ETDEWEB)

Rosa, L.P. [Federal University of Rio de Janeiro (Brazil). School of Engineering; Lomardo, L.L.B. [Fluminense Federal University and Researcher of COPPE, Rio de Janeiro (Brazil). Dept. of Architecture

2004-02-01

Brazil has gone through an important electricity generation crisis in 2001, but the country does not have as yet a legislation to improve building energy efficiency. The energy efficiency of Brazilian buildings can well be improved, as it was shown during the energy-rationing period in 2001. This efficiency increase could usher in gains in quality for indoor environments, as well as lower investments in power generation facilities, including the emission of gases into the atmosphere, flooding arable land for reservoirs, etc. The current work briefly demonstrates the lack of planning that caused the electricity crisis, some results of multi-building studies and simulations of an existing office building of Rio de Janeiro. In this parametric case-study, we have simulated variations of the window-wall ratio (WWR) with different glasses and interior shade, using the natural light, aspects deemed to be of the utmost importance for a future Brazilian building energy efficiency legislation. The need of such legislation has been much increased as a result of the energy generation crisis and its consequences. To take advantage of the problems, in order to improve the quality of the Brazilians buildings, is one of our objectives. (author)

Proactive control for solar energy exploitation: A german high-inertia building case study

International Nuclear Information System (INIS)

Michailidis, Iakovos T.; Baldi, Simone; Pichler, Martin F.; Kosmatopoulos, Elias B.; Santiago, Juan R.

2015-01-01

Highlights: • Solar gains exploitation by utilizing large glass facades and concrete core thermal energy storing capacity. • Efficient Building Energy Management in a well-insulated modern building construction. • Energy consumption reduction by maintaining user comfort. • High inertia large scale office building test case, located in Germany. - Abstract: Energy efficient passive designs and constructions have been extensively studied in the last decades as a way to improve the ability of a building to store thermal energy, increase its thermal mass, increase passive insulation and reduce heat losses. However, many studies show that passive thermal designs alone are not enough to fully exploit the potential for energy efficiency in buildings: in fact, harmonizing the active elements for indoor thermal comfort with the passive design of the building can lead to further improvements in both energy efficiency and comfort. These improvements can be achieved via the design of appropriate Building Optimization and Control (BOC) systems, a task which is more complex in high-inertia buildings than in conventional ones. This is because high thermal mass implies a high memory, so that wrong control decisions will have negative repercussions over long time horizons. The design of proactive control strategies with the capability of acting in advance of a future situation, rather than just reacting to current conditions, is of crucial importance for a full exploitation of the capabilities of a high-inertia building. This paper applies a simulation-assisted control methodology to a high-inertia building in Kassel, Germany. A simulation model of the building is used to proactively optimize, using both current and future information about the external weather condition and the building state, a combined criterion composed of the energy consumption and the thermal comfort index. Both extensive simulation as well as real-life experiments performed during the unstable German

A Software Architecture for Simulation Support in Building Automation

Directory of Open Access Journals (Sweden)

Sergio Leal

2014-07-01

Full Text Available Building automation integrates the active components in a building and, thus, has to connect components of different industries. The goal is to provide reliable and efficient operation. This paper describes how simulation can support building automation and how the deployment process of simulation assisted building control systems can be structured. We look at the process as a whole and map it to a set of formally described workflows that can partly be automated. A workbench environment supports the process execution by means of improved planning, collaboration and deployment. This framework allows integration of existing tools, as well as manual tasks, and is, therefore, many more intricate than regular software deployment tools. The complex environment of building commissioning requires expertise in different domains, especially lighting, heating, ventilation, air conditioning, measurement and control technology, as well as energy efficiency; therefore, we present a framework for building commissioning and describe a deployment process that is capable of supporting the various phases of this approach.

Building Energy Efficiency in India: Compliance Evaluation of Energy Conservation Building Code

Energy Technology Data Exchange (ETDEWEB)

Yu, Sha; Evans, Meredydd; Delgado, Alison

2014-03-26

India is experiencing unprecedented construction boom. The country doubled its floorspace between 2001 and 2005 and is expected to add 35 billion m2 of new buildings by 2050. Buildings account for 35% of total final energy consumption in India today, and building energy use is growing at 8% annually. Studies have shown that carbon policies will have little effect on reducing building energy demand. Chaturvedi et al. predicted that, if there is no specific sectoral policies to curb building energy use, final energy demand of the Indian building sector will grow over five times by the end of this century, driven by rapid income and population growth. The growing energy demand in buildings is accompanied by a transition from traditional biomass to commercial fuels, particularly an increase in electricity use. This also leads to a rapid increase in carbon emissions and aggravates power shortage in India. Growth in building energy use poses challenges to the Indian government. To curb energy consumption in buildings, the Indian government issued the Energy Conservation Building Code (ECBC) in 2007, which applies to commercial buildings with a connected load of 100 kW or 120kVA. It is predicted that the implementation of ECBC can help save 25-40% of energy, compared to reference buildings without energy-efficiency measures. However, the impact of ECBC depends on the effectiveness of its enforcement and compliance. Currently, the majority of buildings in India are not ECBC-compliant. The United Nations Development Programme projected that code compliance in India would reach 35% by 2015 and 64% by 2017. Whether the projected targets can be achieved depends on how the code enforcement system is designed and implemented. Although the development of ECBC lies in the hands of the national government – the Bureau of Energy Efficiency under the Ministry of Power, the adoption and implementation of ECBC largely relies on state and local governments. Six years after ECBC�

Greenhouse gases emission assessment in residential sector through buildings simulations and operation optimization

International Nuclear Information System (INIS)

Stojiljković, Mirko M.; Ignjatović, Marko G.; Vučković, Goran D.

2015-01-01

Buildings use a significant amount of primary energy and largely contribute to greenhouse gases emission. Cost optimality and cost effectiveness, including cost-optimal operation, are important for the adoption of energy efficient and environmentally friendly technologies. The long-term assessment of buildings-related greenhouse gases emission might take into account cost-optimal operation of their energy systems. This is often not the case in the literature. Long-term operation optimization problems are often of large scale and computationally intensive and time consuming. This paper formulates a bottom-up methodology relying on an efficient, but precise operation optimization approach, applicable to long-term problems and use with buildings simulations. We suggest moving-horizon short-term optimization to determine near-optimal operation modes and show that this approach, applied to flexible energy systems without seasonal storage, have satisfactory efficiency and accuracy compared with solving problem for an entire year. We also confirm it as a valuable pre-solve technique. Approach applicability and the importance of energy systems optimization are illustrated with a case study considering buildings envelope improvements and cogeneration and heat storage implementation in an urban residential settlement. EnergyPlus is used for buildings simulations while mixed integer linear programming optimization problems are constructed and solved using the custom-built software and the branch-and-cut solver Gurobi Optimizer. - Highlights: • Bottom-up approach for greenhouse gases emission assessment is presented. • Short-term moving-horizon optimization is used to define operation regimes. • Operation optimization and buildings simulations are connected with modeling tool. • Illustrated optimization method performed efficiently and gave accurate results.

Ecological and Economic Use of Energy by Optimization of Building Construction

International Nuclear Information System (INIS)

Jahrmann, H. J.

1998-01-01

A major part of energy used in daily life is consumed by heating buildings during cold weather periods and for cooling buildings at warmer times. Another major use of energy takes place during production of building materials, construction of the building itself and the depletion and disposal of this building at the end of its lifecycle. Therefore it seems apparent, that effective conservation and saving of energy is a very comprehensive and total approach. The topic is not solely energy saving, it rather is the most effective use of economical and ecological resources. To be energy conscious we have to give closer look to all phases in the existence of a building, and not only of the building. The human being as well must be thoroughly considered in his surrounding, all aspects of his housing suspected for the waste and potential of energy use. So human itself, with his well being in the house, is a major source of energy use. Even the humans health and sickness with its need for cure will cause significant energy input. In the first phase of energy saving programs two aspects should be focused: 1. Primary energy need of construction materials: Primary energy need is the amount of energy used to produce a construction material; from its base origin up to assembling in the housing. Complete ecological balances already exist for a number of materials. Significant difference between materials is observed. The potential for energy saving is impressive. At least 10-30% total energy conservation during the lifecycle of a building appears likely. In many cases a strong positive impact on local economy is expected too. 2. Energy saving by improvement of the thermal quality of buildings: Energy conscious construction of buildings shows an enormous potential for saving. Thermal insulation and effective heating and ventilation systems promise energy savings in the amount of 30-70%. Infrared thermal building analysis and software simulations used prior revitalization of

Energy retrofit of an office building by substitution of the generation system: performance evaluation via dynamic simulation versus current technical standards

International Nuclear Information System (INIS)

Testi, D; Schito, E; Grassi, W; Menchetti, E

2014-01-01

Constructions built in Italy before 1945 (about 30% of the total built stock) feature low energy efficiency. Retrofit actions in this field can lead to valuable energetic and economic savings. In this work, we ran a dynamic simulation of a historical building of the University of Pisa during the heating season. We firstly evaluated the energy requirements of the building and the performance of the existing natural gas boiler, validated with past billings of natural gas. We also verified the energetic savings obtainable by the substitution of the boiler with an air-to-water electrically-driven modulating heat pump, simulated through a cycle-based model, evaluating the main economic metrics. The cycle-based model of the heat pump, validated with manufacturers' data available only at specified temperature and load conditions, can provide more accurate results than the simplified models adopted by current technical standards, thus increasing the effectiveness of energy audits

Internet-based simulation of resource requirement of buildings; Internetbasierte Simulation des Ressourcenbedarfs von Bauwerken

Energy Technology Data Exchange (ETDEWEB)

Neuberg, F.; Rank, E. [Technische Univ. Muenchen, Lehrstuhl fuer Bauinformatik, Muenchen (Germany); Ekkerlein, C.; Faulstich, M. [Technische Univ. Muenchen, Lehrstuhl fuer Wasserguete- und Abfallwirtschaft, Garching (Germany)

2002-12-01

Due to the long life cycle of a building the expenses for usage and maintenance are very high compared to those for the construction, only. About 1/3 of the total energy demand in Germany is used for heating, air-conditioning and hot water supply in buildings. In addition the building wastes resulting for disposal represent a quantitatively enormous material flow. As the most significant decisions are made in early planning steps it is very important to enable planners to estimate the energy demand, resource requirement and ecological impact of different scenarios at this stage. Nowadays more and more architects and engineers use CAD software, like the Architectural Desktop from Autodesk, supporting the generation of three dimensional product models. One prominent model being now well established in the building industry is defined by the Industry Foundation Classes (IFC). This model is also the starting point of our resource oriented design system. To get a basis for a comparative assessment of different design variants it is first necessary to augment the product model with information on resource consumption of the used materials. Therefore a database server accessible via the Internet is developed within our research project providing a service for planners to extend their product model with information necessary for life cycle assessment (LCA) and building energy simulation (EnEV). The data exchange format for the property sets is ifcXML. In our presentation the general software concept together with first simulation tools will be discussed. (orig.)

Monitoring-based HVAC commissioning of an existing office building for energy efficiency

International Nuclear Information System (INIS)

Wang, Liping; Greenberg, Steve; Fiegel, John; Rubalcava, Alma; Earni, Shankar; Pang, Xiufeng; Yin, Rongxin; Woodworth, Spencer; Hernandez-Maldonado, Jorge

2013-01-01

Highlights: ► Demonstrated monitoring-based HVAC commissioning using an existing office building. ► Diagnosed various types of faulty operation in the HVAC system by trend data analyses. ► Identified a list of energy saving measures for the HVAC system. ► Quantified energy saving potential for each commissioning measure using calibrated energy simulation model. ► Achieved an actual energy saving of 10% after the implementations of cost-effective measures. -- Abstract: The performance of Heating, Ventilation and Air Conditioning (HVAC) systems may fail to satisfy design expectations due to improper equipment installation, equipment degradation, sensor failures, or incorrect control sequences. Commissioning identifies and implements cost-effective operational and maintenance measures in buildings to bring them up to the design intent or optimum operation. An existing office building is used as a case study to demonstrate the process of commissioning. Building energy benchmarking tools are applied to evaluate the energy performance for screening opportunities at the whole building level. A large natural gas saving potential was indicated by the building benchmarking results. Faulty operations in the HVAC systems, such as improper operations of air-side economizers, simultaneous heating and cooling, and ineffective optimal start, were identified through trend data analyses and functional testing. The energy saving potential for each commissioning measure is quantified with a calibrated building simulation model. An actual energy saving of 10% was realized after the implementations of cost-effective measures.

An Empirical Validation of Building Simulation Software for Modelling of Double-Skin Facade (DSF)

DEFF Research Database (Denmark)

Larsen, Olena Kalyanova; Heiselberg, Per; Felsmann, Clemens

2009-01-01

buildings, but their accuracy might be limited in cases with DSFs because of the complexity of the heat and mass transfer processes within the DSF. To address this problem, an empirical validation of building models with DSF, performed with various building simulation tools (ESP-r, IDA ICE 3.0, VA114......Double-skin facade (DSF) buildings are being built as an attractive, innovative and energy efficient solution. Nowadays, several design tools are used for assessment of thermal and energy performance of DSF buildings. Existing design tools are well-suited for performance assessment of conventional......, TRNSYS-TUD and BSim) was carried out in the framework of IEA SHC Task 34 /ECBCS Annex 43 "Testing and Validation of Building Energy Simulation Tools". The experimental data for the validation was gathered in a full-scale outdoor test facility. The empirical data sets comprise the key-functioning modes...

Integrated Building Energy Design of a Danish Office Building Based on Monte Carlo Simulation Method

DEFF Research Database (Denmark)

Sørensen, Mathias Juul; Myhre, Sindre Hammer; Hansen, Kasper Kingo

2017-01-01

The focus on reducing buildings energy consumption is gradually increasing, and the optimization of a building’s performance and maximizing its potential leads to great challenges between architects and engineers. In this study, we collaborate with a group of architects on a design project of a new...... office building located in Aarhus, Denmark. Building geometry, floor plans and employee schedules were obtained from the architects which is the basis for this study. This study aims to simplify the iterative design process that is based on the traditional trial and error method in the late design phases...

Window opening behaviour: simulations of occupant behaviour in residential buildings using models based on a field survey

DEFF Research Database (Denmark)

Valentina, Fabi; Andersen, Rune Korsholm; Corgnati, Stefano Paolo

2012-01-01

Window opening behaviour has been shown to have a significant impact on airflow rates and hence energy consumption. Nevertheless, the inhabitant behaviour related to window opening in residential buildings is currently poorly investigated through both field surveys and building energy simulations....... In particular, reliable information regarding user behaviour in residential buildings is crucial for suitable prediction of building performance (energy consumption, indoor environmental quality, etc.). To face this issue, measurements of indoor climate and outdoor environmental parameters and window “opening...... and closing” actions were performed in 15 dwellings from January to August 2008 in Denmark. Probabilistic models of inhabitants’ window “opening and closing” behaviour were developed and implemented in the energy simulation software IDA ICE to improve window opening and closing strategies in simulations...

Development of a methodology for defining whole-building energy design targets for commercial buildings: Phase 2, Development concept stage report

Energy Technology Data Exchange (ETDEWEB)

Jones, J.W. (American Society of Heating, Refrigerating and Air-Conditioning Engineers, Inc., Atlanta, GA (USA)); Deringer, J.J. (Deringer Group, Riva, MD (USA)); Hall, J.D. (American Inst. of Architects, Washington, DC (USA)) (comps.)

1990-09-01

The Whole-Building Energy Design Targets project is being conducted for the US Department of Energy (DOE) by the Pacific Northwest Laboratory (PNL). The objective of the project is to develop a flexible methodology for setting energy performance guidelines with which architects, engineers, planners, and owners can assess energy efficiency in commercial building design. This volume, the third in the four-volume report on the Targets project concept stage, contains the minutes of the workshops as well as summaries of the expert's written comments prepared at the close of each workshop. In Section 2, the building energy simulation workshop is summarized. Section 3 provides a summary of the building cost workshop.

Performative building envelope design correlated to solar radiation and cooling energy consumption

Science.gov (United States)

Jacky, Thiodore; Santoni

2017-11-01

Climate change as an ongoing anthropogenic environmental challenge is predominantly caused by an amplification in the amount of greenhouse gases (GHGs), notably carbon dioxide (CO2) in building sector. Global CO2 emissions are emitted from HVAC (Heating, Ventilation, and Air Conditioning) occupation to provide thermal comfort in building. In fact, the amount of energy used for cooling or heating building is implication of building envelope design. Building envelope acts as interface layer of heat transfer between outdoor environment and the interior of a building. It appears as wall, window, roof and external shading device. This paper examines performance of various design strategy on building envelope to limit solar radiation and reduce cooling loads in tropical climate. The design strategies are considering orientation, window to wall ratio, material properties, and external shading device. This research applied simulation method using Autodesk Ecotect to investigate simultaneously between variations of wall and window ratio, shading device composition and the implication to the amount of solar radiation, cooling energy consumption. Comparative analysis on the data will determine logical variation between opening and shading device composition and cooling energy consumption. Optimizing the building envelope design is crucial strategy for reducing CO2 emissions and long-term energy reduction in building sector. Simulation technology as feedback loop will lead to better performative building envelope.

Intelligent multi-objective optimization for building energy and comfort management

Directory of Open Access Journals (Sweden)

Pervez Hameed Shaikh

2018-04-01

Full Text Available The rapid economic and population growth in developing countries, effective and efficient energy usage has turned out to be crucial due to the rising concern of depleting fossil fuels, of which, one-third of primary energy is consumed in buildings and expected to rise by 53% up to 2030. This roaring sector posing a challenge, due to 90% of people spend most of their time in buildings, requires enhanced well-being of indoor environment and living standards. Therefore, building operations require more energy because most of the energy is consumed to make the indoor environment comfortable. Consequently, there is the need of improved energy efficiency to decrease energy consumption in buildings. In relation to this, the primary challenge of building control systems is the energy consumption and comfort level are generally conflicting to each other. Therefore, an important problem of sustainable smart buildings is to effectively manage the energy consumption and comfort and attain the trade-off between the two. Thus, smart buildings are becoming a trend of future construction that facilitates intelligent control in buildings for the fulfillment of occupant’s comfort level. In this study, an intelligent multi-objective system has been developed with evolutionary multi-objective genetic algorithm (MOGA optimization method. The corresponding case study simulation results for the effective management of users’ comfort and energy efficiency have been carried out. The case study results show the management of energy supply for each comfort parameter and maintain high comfort index achieving balance between the energy consumption and comfort level. Keywords: Energy, Buildings, Comfort, Management, Optimization, Trade-off

Net positive energy buildings

International Nuclear Information System (INIS)

Romero, A.; Barreiro, E.; Sanchez Zabala, V.

2010-01-01

Buildings are great consumers of energy, being responsible for almost 36% of CO2 emissions in Europe. Though there are many initiatives towards the reduction of energy consumption and CO2 emissions in buildings, many of the alternatives are diminished due to a lack of a unique and holistic approach to the problem. This paper reports a new innovative concept of Positive Energy Buildings (EB+), as well as an integral methodology that covers the overall design process for achieving them. The methodology evaluates energy efficiency solutions at different scales, from building site to generation systems. An educational building design in Navarra serves as a case study to check the feasibility of the proposed methodology. The study concludes that the key to achieve a Positive Energy Building is a minimized energy demand, complemented by efficient facilities and enhanced by distributed power generation from renewable sources. (Author).

Energy management systems in buildings

Energy Technology Data Exchange (ETDEWEB)

Lush, D. M.

1979-07-01

An investigation is made of the range of possibilities available from three types of systems (automatic control devices, building envelope, and the occupants) in buildings. The following subjects are discussed: general (buildings, design and personnel); new buildings (envelope, designers, energy and load calculations, plant design, general design parameters); existing buildings (conservation measures, general energy management, air conditioned buildings, industrial buildings); man and motivation (general, energy management and documentation, maintenance, motivation); automatic energy management systems (thermostatic controls, optimized plant start up, air conditioned and industrial buildings, building automatic systems). (MCW)

Energy - efficient buildings in pakistan

International Nuclear Information System (INIS)

Sohail, M.; Qureshi, M.U.D.

2011-01-01

Pakistan is one of the countries with the highest energy consumption for domestic use. Annual energy consumption by the domestic sector is 45.9 % of the total, while the industrial sector, consumes about 27.5%. About half of the total energy consumed is used in buildings and/or heating, ventilation and air-conditioning (HVAC) and lighting appliances. The energy consumed for the same purposes in China and UK is 25 to 30 % and 40 %, respectively, even in extreme weather conditions. Energy deficiency in Pakistan is approximately 5,000 MWe, which results in worst load-shedding in summers and, lately, even in winters. Building new energy sources like dams, coal power plants and renewable energy power projects are some possible solutions, but these are time taking and need at least 2 to 6 years to complete, depending upon the nature of the project. Fast development of energy-efficient buildings is, therefore, necessary to deal with exacerbating energy-crisis and related environmental impact in Pakistan. Innovations in the prevailing building-design will help the country in reducing the energy burden. These innovations may include improved architectural designs, energy-efficient building materials, electrical appliances and implementation of building energy-efficiency codes. In 1987, the National Energy Conservation Centre (ENERCON), was established under Ministry of Environment, Government of Pakistan, with the aim to build awareness among the masses for energy conservation, and to make policies regarding energy-conservation structures in the country. But no policy regarding building energy codes has been introduced by ENERCON till now. In collaboration with Pakistan Engineering Council (PEC), ENERCON has recently finalized the Building Energy Code of Pakistan Energy Provisions 2011 for which statutory notification is under process for necessary amendment in the building by-laws. The implementation of this Energy Code will result in 25 to 30 % of energy savings in the

Climate impacts on extreme energy consumption of different types of buildings.

Science.gov (United States)

Li, Mingcai; Shi, Jun; Guo, Jun; Cao, Jingfu; Niu, Jide; Xiong, Mingming

2015-01-01

Exploring changes of building energy consumption and its relationships with climate can provide basis for energy-saving and carbon emission reduction. Heating and cooling energy consumption of different types of buildings during 1981-2010 in Tianjin city, was simulated by using TRNSYS software. Daily or hourly extreme energy consumption was determined by percentile methods, and the climate impact on extreme energy consumption was analyzed. The results showed that days of extreme heating consumption showed apparent decrease during the recent 30 years for residential and large venue buildings, whereas days of extreme cooling consumption increased in large venue building. No significant variations were found for the days of extreme energy consumption for commercial building, although a decreasing trend in extreme heating energy consumption. Daily extreme energy consumption for large venue building had no relationship with climate parameters, whereas extreme energy consumption for commercial and residential buildings was related to various climate parameters. Further multiple regression analysis suggested heating energy consumption for commercial building was affected by maximum temperature, dry bulb temperature, solar radiation and minimum temperature, which together can explain 71.5 % of the variation of the daily extreme heating energy consumption. The daily extreme cooling energy consumption for commercial building was only related to the wet bulb temperature (R2= 0.382). The daily extreme heating energy consumption for residential building was affected by 4 climate parameters, but the dry bulb temperature had the main impact. The impacts of climate on hourly extreme heating energy consumption has a 1-3 hour delay in all three types of buildings, but no delay was found in the impacts of climate on hourly extreme cooling energy consumption for the selected buildings.

Analysis of Solar Energy Use for Multi-Flat Buildings Renovation

Directory of Open Access Journals (Sweden)

Kęstutis Valančius

2016-10-01

Full Text Available The paper analyses the energy and financial possibilities to install renewable energy sources (solar energy generating systems when renovating multi-flat buildings. The aim is to analyse solar energy system possibilities for modernization of multi-flat buildings (5-storey, 9-storey and 16-storey, providing detailed conclusions about the appropriateness of the energy systems and financial aspects. It is also intended to determine the optimal technological combinations and solutions to reach the maximum energy benefits. For the research computer simulation tools “EnergyPRO” and “PV*SOL Premium” are chosen. Also actual collected heat and electricity consumption data is used for the analysis.

Cost-optimal energy performance renovation measures of educational buildings in cold climate

International Nuclear Information System (INIS)

Niemelä, Tuomo; Kosonen, Risto; Jokisalo, Juha

2016-01-01

Highlights: • The proposed national nZEB target can be cost-effectively achieved in renovations. • Energy saving potential of HVAC systems is significant compared to the building envelope. • Modern renewable energy production technologies are cost-efficient and recommendable. • Improving the indoor climate conditions in deep renovations is recommendable. • Simulation-based optimization method is efficient in building performance analyzes. - Abstract: The paper discusses cost-efficient energy performance renovation measures for typical educational buildings built in the 1960s and 1970s in cold climate regions. The study analyzes the impact of different energy renovation measures on the energy efficiency and economic viability in a Finnish case study educational building located in Lappeenranta University of Technology (LUT) campus area. The main objective of the study was to determine the cost-optimal energy performance renovation measures to meet the proposed national nearly zero-energy building (nZEB) requirements, which are defined according to the primary energy consumption of buildings. The main research method of the study was simulation-based optimization (SBO) analysis, which was used to determine the cost-optimal renovation solutions. The results of the study indicate that the minimum national energy performance requirement of new educational buildings (E_p_r_i_m_a_r_y ⩽ 170 kWh/(m"2,a)) can be cost-effectively achieved in deep renovations of educational buildings. In addition, the proposed national nZEB-targets are also well achievable, while improving the indoor climate (thermal comfort and indoor air quality) conditions significantly at the same time. Cost-effective solutions included renovation of the original ventilation system, a ground source heat pump system with relatively small dimensioning power output, new energy efficient windows and a relatively large area of PV-panels for solar-based electricity production. The results and

Energy Analysis at a Near Zero Energy Building. A Case-Study in Spain

Directory of Open Access Journals (Sweden)

Javier M. Rey-Hernández

2018-04-01

Full Text Available This paper develops an energy analysis for an existing near Zero Energy (nZEB and Zero Carbon Emissions building called LUCIA, located at the university campus in Valladolid (Spain. It is designed to supply electricity, cooling and heating needs through solar energy (Photovoltaic Systems, PV, biomass and an Earth–Air Heat Exchanger (EAHE, besides a Combined Heat Power (CHP. It is currently among the top three buildings with the highest LEED certification in the World. The building model is simulated with DesignBuilder version 5. The results of the energy analysis illustrate the heating, cooling and lighting consumptions expected, besides other demands and energy uses. From this data, we carried out an energy balance of the nZEB, which will help to plan preventive actions when compared to the actual energy consumptions, improving the management and control of both the building and its systems. The primary energy indicator obtained is 67 kWh/m2 a year, and 121 kWh/m2 a year for renewable energy generation, with respect to 55 kWh/m2 and 45 kWh/m2 set as reference in Europe. The Renewable Energy Ratio (RER is 0.66. These indicators become a useful tool for the energy analysis of the nZEB according to the requirements in the European regulations and for its comparison with further nZEB.

Using Coupled Energy, Airflow and IAQ Software (TRNSYS/CONTAM) to Evaluate Building Ventilation Strategies.

Science.gov (United States)

Dols, W Stuart; Emmerich, Steven J; Polidoro, Brian J

2016-03-01

Building energy analysis tools are available in many forms that provide the ability to address a broad spectrum of energy-related issues in various combinations. Often these tools operate in isolation from one another, making it difficult to evaluate the interactions between related phenomena and interacting systems, forcing oversimplified assumptions to be made about various phenomena that could otherwise be addressed directly with another tool. One example of such interdependence is the interaction between heat transfer, inter-zone airflow and indoor contaminant transport. In order to better address these interdependencies, the National Institute of Standards and Technology (NIST) has developed an updated version of the multi-zone airflow and contaminant transport modelling tool, CONTAM, along with a set of utilities to enable coupling of the full CONTAM model with the TRNSYS simulation tool in a more seamless manner and with additional capabilities that were previously not available. This paper provides an overview of these new capabilities and applies them to simulating a medium-size office building. These simulations address the interaction between whole-building energy, airflow and contaminant transport in evaluating various ventilation strategies including natural and demand-controlled ventilation. CONTAM has been in practical use for many years allowing building designers, as well as IAQ and ventilation system analysts, to simulate the complex interactions between building physical layout and HVAC system configuration in determining building airflow and contaminant transport. It has been widely used to design and analyse smoke management systems and evaluate building performance in response to chemical, biological and radiological events. While CONTAM has been used to address design and performance of buildings implementing energy conserving ventilation systems, e.g., natural and hybrid, this new coupled simulation capability will enable users to apply the

Rev-Changes in Primary Energy Use and CO2 Emissions—An Impact Assessment for a Building with Focus on the Swedish Proposal for Nearly Zero Energy Buildings

Directory of Open Access Journals (Sweden)

Mattias Gustafsson

2017-07-01

Full Text Available In the European Union’s Energy Performance of Buildings Directive, the energy efficiency goal for buildings is set in terms of primary energy use. In the proposal from the National Board of Housing, Building, and Planning, for nearly zero energy buildings in Sweden, the use of primary energy is expressed as a primary energy number calculated with given primary energy factors. In this article, a multi-dwelling building is simulated and the difference in the primary energy number is investigated when the building uses heat from district heating systems or from heat pumps, alone or combined with solar thermal or solar photovoltaic systems. It is also investigated how the global CO2 emissions are influenced by the different energy system combinations and with different fuels used. It is concluded that the calculated primary energy number is lower for heat pump systems, but the global CO2 emissions are lowest when district heating uses mostly biofuels and is combined with solar PV systems. The difference is up to 140 tonnes/year. If the aim with the Swedish building code is to decrease the global CO2 emissions then the ratio between the primary energy factors for electricity and heat should be larger than three and considerably higher than today.

The effect of using low-polluting building materials on ventilation requirements and energy use in buildings

Energy Technology Data Exchange (ETDEWEB)

Wargocki, P.; Frontczak, M. (International Centre for Indoor Environment and Energy, Dept. of Mechanical Engineering, DTU, Kgs. Lyngby (DK)); Knudsen, Henrik N. (Danish Building Research Institute, Aalborg Univ., Hoersholm (DK))

2007-07-01

The main objective of the ongoing research project described in this paper was to study the potential for reducing energy used for ventilating buildings by using low-polluting building materials, without compromising the indoor air quality. To quantify this potential, the exposure-response relationships, i.e. the relationships between ventilation rate and perceived indoor air quality, were established for rooms furnished with different categories of polluting materials and the simulations of energy used for ventilation were carried out. The exposure-response relationships were based on a summary of data reported in the literature on exposure-response relationships for materials tested in laboratory settings in small-scale glass chambers, and in full-scale in climate chambers, test rooms or normal offices. New experiments were also considered in which the effect of using low-polluting materials on perceived air quality was examined in test rooms ventilated with different outdoor air supply rates, low-polluting materials being selected in small glass chambers. The results suggest that the exposure-response relationships vary between different building materials and that the perceived air quality can be improved considerably when polluting building materials are substituted with materials that pollute less. The preliminary energy simulations indicate that selecting low-polluting materials will result in considerable energy savings as a result of reducing the ventilation rates required to achieve acceptable indoor air quality. (au)

Smart Building: Decision Making Architecture for Thermal Energy Management.

Science.gov (United States)

Uribe, Oscar Hernández; Martin, Juan Pablo San; Garcia-Alegre, María C; Santos, Matilde; Guinea, Domingo

2015-10-30

Smart applications of the Internet of Things are improving the performance of buildings, reducing energy demand. Local and smart networks, soft computing methodologies, machine intelligence algorithms and pervasive sensors are some of the basics of energy optimization strategies developed for the benefit of environmental sustainability and user comfort. This work presents a distributed sensor-processor-communication decision-making architecture to improve the acquisition, storage and transfer of thermal energy in buildings. The developed system is implemented in a near Zero-Energy Building (nZEB) prototype equipped with a built-in thermal solar collector, where optical properties are analysed; a low enthalpy geothermal accumulation system, segmented in different temperature zones; and an envelope that includes a dynamic thermal barrier. An intelligent control of this dynamic thermal barrier is applied to reduce the thermal energy demand (heating and cooling) caused by daily and seasonal weather variations. Simulations and experimental results are presented to highlight the nZEB thermal energy reduction.

Smart Building: Decision Making Architecture for Thermal Energy Management

Directory of Open Access Journals (Sweden)

Oscar Hernández Uribe

2015-10-01

Full Text Available Smart applications of the Internet of Things are improving the performance of buildings, reducing energy demand. Local and smart networks, soft computing methodologies, machine intelligence algorithms and pervasive sensors are some of the basics of energy optimization strategies developed for the benefit of environmental sustainability and user comfort. This work presents a distributed sensor-processor-communication decision-making architecture to improve the acquisition, storage and transfer of thermal energy in buildings. The developed system is implemented in a near Zero-Energy Building (nZEB prototype equipped with a built-in thermal solar collector, where optical properties are analysed; a low enthalpy geothermal accumulation system, segmented in different temperature zones; and an envelope that includes a dynamic thermal barrier. An intelligent control of this dynamic thermal barrier is applied to reduce the thermal energy demand (heating and cooling caused by daily and seasonal weather variations. Simulations and experimental results are presented to highlight the nZEB thermal energy reduction.

Assessment of Energy Impact of Window Technologies for Commercial Buildings

Energy Technology Data Exchange (ETDEWEB)

Hong, Tianzhen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Selkowitz, Stephen [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division; Yazdanian, Mehry [Lawrence Berkeley National Lab. (LBNL), Berkeley, CA (United States). Environmental Energy Technologies Division

2009-10-01

Windows play a significant role in commercial buildings targeting the goal of net zero energy. This report summarizes research methodology and findings in evaluating the energy impact of windows technologies for commercial buildings. The large office prototypical building, chosen from the DOE commercial building benchmarks, was used as the baseline model which met the prescriptive requirements of ASHRAE Standard 90.1-2004. The building simulations were performed with EnergyPlus and TMY3 weather data for five typical US climates to calculate the energy savings potentials of six windows technologies when compared with the ASHRAE 90.1-2004 baseline windows. The six windows cover existing, new, and emerging technologies, including ASHRAE 189.1 baseline windows, triple pane low-e windows, clear and tinted double pane highly insulating low-e windows, electrochromic (EC) windows, and highly insulating EC windows representing the hypothetically feasible optimum windows. The existing stocks based on average commercial windows sales are included in the analysis for benchmarking purposes.

Using DOE Commercial Reference Buildings for Simulation Studies: Preprint

Energy Technology Data Exchange (ETDEWEB)

Field, K.; Deru, M.; Studer, D.

2010-08-01

The U.S. Department of Energy developed 256 EnergyPlus models for use in studies that aim to characterize about 70% of the U.S. commercial building stock. Sixteen building types - including restaurants, health care, schools, offices, supermarkets, retail, lodging, and warehouses - are modeled across 16 cities to represent the diversity of U.S. climate zones. Weighting factors have been developed to combine the models in proportions similar to those of the McGraw-Hill Construction Projects Starts Database for 2003-2007. This paper reviews the development and contents of these models and their applications in simulation studies.

Energy savings potential from improved building controls for the US commercial building sector

Energy Technology Data Exchange (ETDEWEB)

Fernandez, Nick; Katipamula, Srinivas; Wang, Weimin; Xie, Yulong; Zhao, Mingjie

2017-09-27

The U.S. Department of Energy’s (DOE’s) Building Technologies Office (BTO) sponsored a study to determine the potential national savings achievable in the commercial building sector through widespread deployment of best practice controls, elimination of system and component faults, and use of better sensing. Detailed characterization of potential savings was one source of input to set research, development, and deployment (RD&D) goals in the field of building sensors and controls. DOE’s building energy simulation software, EnergyPlus, was employed to estimate the potential savings from 34 measures in 9 building types and across 16 climates representing almost 57% of commercial building sector energy consumption. In addition to estimating savings from individual measures, three packages of measures were created to estimate savings from the packages. These packages represented an 1) efficient building, 2) typical building, and 3) inefficient building. To scale the results from individual measures or a package to the national scale, building weights by building type and climate locations from the Energy Information Administration’s 2012 Commercial Building Energy Consumption Survey (CBECS) were used. The results showed significant potential for energy savings across all building types and climates. The total site potential savings from individual measures by building type and climate location ranged between 0% and 25%. The total site potential savings by building type aggregated across all climates (using the CBECS building weights) for each measure varied between 0% and 16%. The total site potential savings aggregated across all building types and climates for each measure varied between 0% and 11%. Some individual measures had negative savings because correcting underlying operational problems (e.g., inadequate ventilation) resulted in increased energy consumption. When combined into packages, the overall national savings potential is estimated to be 29

Mixed strategies for energy conservation and alternative energy utilization (solar) in buildings. Final report. Volume III. Appendixes. [10 appendices

Energy Technology Data Exchange (ETDEWEB)

None

1977-06-01

This appendix summarizes building characteristics used to determine heating and cooling loads for each of the five building types in each of the four regions. For the selected five buildings, the following data are attached: new and existing construction characteristics; new and existing construction thermal resistance; floor plan and elevation; people load schedule; lighting load schedule; appliance load schedule; ventilation schedule; and hot water use schedule. For the five building types (single family, apartment buildings, commercial buildings, office buildings, and schools), data are compiled in 10 appendices. These are Building Characteristics; Alternate Energy Sources and Energy Conservation Techniques Description, Costs, Fuel Price Scenarios; Life Cycle Cost Model; Simulation Models; Solar Heating/Cooling System; Condensed Weather; Single and Multi-Family Dwelling Characteristics and Energy Conservation Techniques; Mixed Strategies for Energy Conservation and Alternative Energy Utilization in Buildings. An extensive bibliography is given in the final appendix. (MCW)

Compliance with building energy regulations for new-build dwellings

International Nuclear Information System (INIS)

Pan, Wei; Garmston, Helen

2012-01-01

Despite increasingly stringent building energy regulations worldwide, non-compliance exists in practice. This paper examines the profile of compliance with building energy regulations for new-build dwellings. In total 404 new-build dwellings completed in the UK from 2006 to 2009 were investigated. Only a third of these dwellings were evidenced as being compliant with Building Regulations Part L (England and Wales). Such low compliance casts a serious concern over the achievability of the UK Government's target for all new-build homes to be ‘zero carbon’ from 2016. Clearly evidenced was a lack of knowledge of Part L and its compliance requirements among the supply and building control sides of new-build dwellings. The results also indicate that the compliance profile was influenced by factors including Standard Assessment Procedure (UK Government's methodology for energy efficiency) calculation submissions, learning and experience of builders and building controls with Part L, use of Part L1A checklist, the introduction of energy performance certificate (EPC), build method, dwelling type, and project size. Better compliance was associated with flats over houses and timber frame over masonry. The use of EPC and Part L1A checklist should be encouraged. Key to addressing the lack of compliance with building energy regulations is training. -- Highlights: ► There exists a lack of compliance, worldwide, with building energy regulations. ► The implementation of England and Wales building energy regulations is problematic. ► Training, learning and experience of builders and building control are critical. ► Energy performance certificate and Part L 2006 checklist helped achieve compliance. ► Flats achieved better compliance over houses; and timber frame over masonry.

Building Energy Monitoring and Analysis

Energy Technology Data Exchange (ETDEWEB)

Hong, Tianzhen; Feng, Wei; Lu, Alison; Xia, Jianjun; Yang, Le; Shen, Qi; Im, Piljae; Bhandari, Mahabir

2013-06-01

This project aimed to develop a standard methodology for building energy data definition, collection, presentation, and analysis; apply the developed methods to a standardized energy monitoring platform, including hardware and software, to collect and analyze building energy use data; and compile offline statistical data and online real-time data in both countries for fully understanding the current status of building energy use. This helps decode the driving forces behind the discrepancy of building energy use between the two countries; identify gaps and deficiencies of current building energy monitoring, data collection, and analysis; and create knowledge and tools to collect and analyze good building energy data to provide valuable and actionable information for key stakeholders.

Impacts of Climate Change on Energy Consumption and Peak Demand in Buildings: A Detailed Regional Approach

Energy Technology Data Exchange (ETDEWEB)

Dirks, James A.; Gorrissen, Willy J.; Hathaway, John E.; Skorski, Daniel C.; Scott, Michael J.; Pulsipher, Trenton C.; Huang, Maoyi; Liu, Ying; Rice, Jennie S.

2015-01-01

This paper presents the results of numerous commercial and residential building simulations, with the purpose of examining the impact of climate change on peak and annual building energy consumption over the portion of the Eastern Interconnection (EIC) located in the United States. The climate change scenario considered (IPCC A2 scenario as downscaled from the CASCaDE data set) has changes in mean climate characteristics as well as changes in the frequency and duration of intense weather events. This investigation examines building energy demand for three annual periods representative of climate trends in the CASCaDE data set at the beginning, middle, and end of the century--2004, 2052, and 2089. Simulations were performed using the Building ENergy Demand (BEND) model which is a detailed simulation platform built around EnergyPlus. BEND was developed in collaboration with the Platform for Regional Integrated Modeling and Analysis (PRIMA), a modeling framework designed to simulate the complex interactions among climate, energy, water, and land at decision-relevant spatial scales. Over 26,000 building configurations of different types, sizes, vintages, and, characteristics which represent the population of buildings within the EIC, are modeled across the 3 EIC time zones using the future climate from 100 locations within the target region, resulting in nearly 180,000 spatially relevant simulated demand profiles for each of the 3 years. In this study, the building stock characteristics are held constant based on the 2005 building stock in order to isolate and present results that highlight the impact of the climate signal on commercial and residential energy demand. Results of this analysis compare well with other analyses at their finest level of specificity. This approach, however, provides a heretofore unprecedented level of specificity across multiple spectrums including spatial, temporal, and building characteristics. This capability enables the ability to

Climate impacts on extreme energy consumption of different types of buildings.

Directory of Open Access Journals (Sweden)

Mingcai Li

Full Text Available Exploring changes of building energy consumption and its relationships with climate can provide basis for energy-saving and carbon emission reduction. Heating and cooling energy consumption of different types of buildings during 1981-2010 in Tianjin city, was simulated by using TRNSYS software. Daily or hourly extreme energy consumption was determined by percentile methods, and the climate impact on extreme energy consumption was analyzed. The results showed that days of extreme heating consumption showed apparent decrease during the recent 30 years for residential and large venue buildings, whereas days of extreme cooling consumption increased in large venue building. No significant variations were found for the days of extreme energy consumption for commercial building, although a decreasing trend in extreme heating energy consumption. Daily extreme energy consumption for large venue building had no relationship with climate parameters, whereas extreme energy consumption for commercial and residential buildings was related to various climate parameters. Further multiple regression analysis suggested heating energy consumption for commercial building was affected by maximum temperature, dry bulb temperature, solar radiation and minimum temperature, which together can explain 71.5 % of the variation of the daily extreme heating energy consumption. The daily extreme cooling energy consumption for commercial building was only related to the wet bulb temperature (R2= 0.382. The daily extreme heating energy consumption for residential building was affected by 4 climate parameters, but the dry bulb temperature had the main impact. The impacts of climate on hourly extreme heating energy consumption has a 1-3 hour delay in all three types of buildings, but no delay was found in the impacts of climate on hourly extreme cooling energy consumption for the selected buildings.

Comparison of Demand Response Performance with an EnergyPlus Model in a Low Energy Campus Building

Energy Technology Data Exchange (ETDEWEB)

Dudley, Junqiao Han; Black, Doug; Apte, Mike; Piette, Mary Ann; Berkeley, Pam

2010-05-14

We have studied a low energy building on a campus of the University of California. It has efficient heating, ventilation, and air conditioning (HVAC) systems, consisting of a dual-fan/dual-duct variable air volume (VAV) system. As a major building on the campus, it was included in two demand response (DR) events in the summers of 2008 and 2009. With chilled water supplied by thermal energy storage in the central plant, cooling fans played a critical role during DR events. In this paper, an EnergyPlus model of the building was developed and calibrated. We compared both whole-building and HVAC fan energy consumption with model predictions to understand why demand savings in 2009 were much lower than in 2008. We also used model simulations of the study building to assess pre-cooling, a strategy that has been shown to improve demand saving and thermal comfort in many types of building. This study indicates a properly calibrated EnergyPlus model can reasonably predict demand savings from DR events and can be useful for designing or optimizing DR strategies.

Simulation-based method to determine climatic energy strategies of an adaptable building retrofit façade system

International Nuclear Information System (INIS)

Capeluto, I. Guedi; Ochoa, Carlos E.

2014-01-01

Vast amounts of the European residential stock were built with limited consideration for energy efficiency, yet its refurbishment can help reach national energy reduction goals, decreasing environmental impact. Short-term retrofits with reduced interference to inhabitants can be achieved by upgrading facades with elements that enhance energy efficiency and user comfort. The European Union-funded Meefs Retrofitting (Multifunctional Energy Efficient Façade System) project aims to develop an adaptable mass-produced facade system for energy improvement in existing residential buildings throughout the continent. This article presents a simplified methodology to identify preferred strategies and combinations for the early design stages of such system. This was derived from studying weather characteristics of European regions and outlining climatic energy-saving strategies based on human thermal comfort. Strategies were matched with conceptual technologies like glazing, shading and insulation. The typical building stock was characterized from statistics of previous European projects. Six improvements and combinations were modelled using a simulation model, identifying and ranking preferred configurations. The methodology is summarized in a synoptic scheme identifying the energy rankings of each improvement and combination for the studied climates and façade orientations. - Highlights: • First results of EU project for new energy efficient façade retrofit system. • System consists of prefabricated elements with multiple options for flexibility. • Modular strategies were determined that adapt to different climates. • Technologies matching the strategies were identified. • Presents a method for use and application in different climates across Europe

Development of surrogate models using artificial neural network for building shell energy labelling

International Nuclear Information System (INIS)

Melo, A.P.; Cóstola, D.; Lamberts, R.; Hensen, J.L.M.

2014-01-01

Surrogate models are an important part of building energy labelling programs, but these models still present low accuracy, particularly in cooling-dominated climates. The objective of this study was to evaluate the feasibility of using an artificial neural network (ANN) to improve the accuracy of surrogate models for labelling purposes. An ANN was applied to model the building stock of a city in Brazil, based on the results of extensive simulations using the high-resolution building energy simulation program EnergyPlus. Sensitivity and uncertainty analyses were carried out to evaluate the behaviour of the ANN model, and the variations in the best and worst performance for several typologies were analysed in relation to variations in the input parameters and building characteristics. The results obtained indicate that an ANN can represent the interaction between input and output data for a vast and diverse building stock. Sensitivity analysis showed that no single input parameter can be identified as the main factor responsible for the building energy performance. The uncertainty associated with several parameters plays a major role in assessing building energy performance, together with the facade area and the shell-to-floor ratio. The results of this study may have a profound impact as ANNs could be applied in the future to define regulations in many countries, with positive effects on optimizing the energy consumption. - Highlights: • We model several typologies which have variation in input parameters. • We evaluate the accuracy of surrogate models for labelling purposes. • ANN is applied to model the building stock. • Uncertainty in building plays a major role in the building energy performance. • Results show that ANN could help to develop building energy labelling systems

A study of the passive cooling potential in simulated building in Latvian climate conditions

Science.gov (United States)

Prozuments, A.; Vanags, I.; Borodinecs, A.; Millers, R.; Tumanova, K.

2017-10-01

In this paper authors point out that overheating in buildings during summer season is a major problem in moderate and cold climates, not only in warm climate zones. Mostly caused by solar heat gains, especially in buildings with large glazed areas overheating is a common problem in recently constructed low-energy buildings. At the same time, comfort demands are increasing. While heating loads can be decreased by improving the insulation of the building envelope, cooling loads are also affecting total energy demand. Passive cooling solutions allow reduction of heat gains, and thus reducing the cooling loads. There is a significant night cooling potential with low temperatures at night during summer in moderate and cold climates. Night cooling is based on cooling of buildings thermal mass during the night and heat accumulation during the day. This approach allows to provide thermal comfort, reducing cooling loads during the day. Authors investigate thermal comfort requirements and causes for discomfort. Passive cooling methods are described. The simulation modeling is carried out to analyze impact of constructions and building orientation on energy consumption for cooling using the IDA-ICE software. Main criteria for simulation analysis are energy consumption for cooling and thermal comfort.

The Impact of Insulation and HVAC Degradation on Overall Building Energy Performance: A Case Study

Directory of Open Access Journals (Sweden)

Georgios Eleftheriadis

2018-02-01

Full Text Available Through monitoring of buildings, it can be proven that the performance of envelope elements and energy supply systems deteriorates with time. The results of this degradation are higher energy consumption and life cycle costs than projected in the building design phase. This paper considers the impacts of this deterioration on the whole building energy performance with the goal of improving the accuracy of long term performance calculations. To achieve that, simplified degradation equations found in literature are applied on selected envelope elements and heating system components of a single-family house in Germany. The energy performance of the building over 20 years is determined through simulations by EnergyPlus and MATLAB. The simulation results show that, depending on maintenance and primary heating system, the building can consume between 18.4% and 47.1% more primary energy over 20 years compared to a scenario in which no degradation were to occur. Thus, it can be concluded that considering performance drop with time is key in order to improve the decision-making process when designing future-proof buildings.

Building Energy Monitoring and Analysis

Energy Technology Data Exchange (ETDEWEB)

Hong, Tianzhen; Feng, Wei; Lu, Alison; Xia, Jianjun; Yang, Le; Shen, Qi; Im, Piljae; Bhandari, Mahabir

2013-06-01

U.S. and China are the world’s top two economics. Together they consumed one-third of the world’s primary energy. It is an unprecedented opportunity and challenge for governments, researchers and industries in both countries to join together to address energy issues and global climate change. Such joint collaboration has huge potential in creating new jobs in energy technologies and services. Buildings in the US and China consumed about 40% and 25% of the primary energy in both countries in 2010 respectively. Worldwide, the building sector is the largest contributor to the greenhouse gas emission. Better understanding and improving the energy performance of buildings is a critical step towards sustainable development and mitigation of global climate change. This project aimed to develop a standard methodology for building energy data definition, collection, presentation, and analysis; apply the developed methods to a standardized energy monitoring platform, including hardware and software, to collect and analyze building energy use data; and compile offline statistical data and online real-time data in both countries for fully understanding the current status of building energy use. This helps decode the driving forces behind the discrepancy of building energy use between the two countries; identify gaps and deficiencies of current building energy monitoring, data collection, and analysis; and create knowledge and tools to collect and analyze good building energy data to provide valuable and actionable information for key stakeholders.

End-use energy consumption estimates for U.S. commercial buildings, 1992

Energy Technology Data Exchange (ETDEWEB)

Belzer, D.B.; Wrench, L.E.

1997-03-01

An accurate picture of how energy is used in the nation`s stock of commercial buildings can serve a variety of program planning and policy needs of the US Department of Energy, utilities, and other groups seeking to improve the efficiency of energy use in the building sector. This report describes an estimation of energy consumption by end use based upon data from the 1992 Commercial Building Energy Consumption Survey (CBECS). The methodology used in the study combines elements of engineering simulations and statistical analysis to estimate end-use intensities for heating, cooling, ventilation, lighting, refrigeration, hot water, cooking, and miscellaneous equipment. Statistical Adjusted Engineering (SAE) models were estimated by building type. The nonlinear SAE models used variables such as building size, vintage, climate region, weekly operating hours, and employee density to adjust the engineering model predicted loads to the observed consumption (based upon utility billing information). End-use consumption by fuel was estimated for each of the 6,751 buildings in the 1992 CBECS. The report displays the summary results for 11 separate building types as well as for the total US commercial building stock. 4 figs., 15 tabs.

Intelligent energy buildings based on RES and nanotechnology

Energy Technology Data Exchange (ETDEWEB)

Kaplanis, S., E-mail: kaplanis@teipat.gr; Kaplani, E. [R.E.S. Laboratory, Mechanical Engineering Dept., Technological Educational Institute of Western Greece M. Alexandrou 1, Koukouli 26 334, Patra (Greece)

2015-12-31

The paper presents the design features, the energy modelling and optical performance details of two pilot Intelligent Energy Buildings, (IEB). Both are evolution of the Zero Energy Building (ZEB) concept. RES innovations backed up by signal processing, simulation models and ICT tools were embedded into the building structures in order to implement a new predictive energy management concept. In addition, nano-coatings, produced by TiO2 and ITO nano-particles, were deposited on the IEB structural elements and especially on the window panes and the PV glass covers. They exhibited promising SSP values which lowered the cooling loads and increased the PV modules yield. Both pilot IEB units were equipped with an on-line dynamic hourly solar radiation prediction model, implemented by sensors and the related software to manage effectively the energy source, the loads and the storage or the backup system. The IEB energy sources covered the thermal loads via a south façade embedded in the wall and a solar roof which consists of a specially designed solar collector type, while a PV generator is part of the solar roof, like a compact BIPV in hybrid configuration to a small wind turbine.

Assessment of building integrated energy supply and energy saving schemes on a national level in Denmark

Energy Technology Data Exchange (ETDEWEB)

Muenster, M.; Morthorst, P.E.; Birkl, C.

2011-06-15

In the future, buildings will not only act as consumers of energy but as producers as well. For these ''prosumers'', energy production by use of solar panels, photovoltaics and heat pumps etc will be essential. The objective of this project was to find the most optimal combinations of building insulation and use of renewable energy sources in existing buildings in terms of economics and climate impacts. Five houses were analyzed based on different personal load, consumption profiles, solar orientation and proposed building envelope improvements and use of combinations of renewable energy systems. The results of these analyses were integrated in five scenarios to examine the consequences at national level of implementing insulation together with solar panels, photovoltaics and heat pumps in single-family houses. The simulations focused on the building period between 1961 and 1972 characterised by high building activity and low energy performance. The five scenarios - a baseline scenario, a maximum savings scenario, a maximum production scenario, and a combination scenario - showed that regardless of scenario, a consequent use of individual heat pumps leads to the greatest energy savings and CO{sub 2} reductions. (ln)

Building energy governance in Shanghai

Science.gov (United States)

Kung, YiHsiu Michelle

With Asia's surging economies and urbanization, the region is adding to its built environment at an unprecedented rate, especially those population centers in China and India. With numerous existing buildings, plus a new building boom, construction in these major Asian cities has caused momentous sustainability challenges. This dissertation focuses on China's leading city, Shanghai, to explore and assess its existing commercial building energy policies and practices. Research estimates that Shanghai's commercial buildings might become a key challenge with regard to energy use and CO2 emissions as compared to other major Asian cities. Relevant building energy policy instruments at national and local levels for commercial buildings are reviewed. In addition, two benchmarks are established to further assess building energy policies in Shanghai. The first benchmark is based on the synthesis of relevant criteria and policy instruments as recommended by professional organizations, while the second practical benchmark is drawn from an analysis of three global cities: New York, London and Tokyo. Moreover, two large-scale commercial building sites - Shanghai IKEA and Plaza 66 - are selected for investigation and assessment of their efforts on building energy saving measures. Detailed building energy savings, CO2 reductions, and management cost reductions based on data availability and calculations are presented with the co-benefits approach. The research additionally analyzes different interventions and factors that facilitate or constrain the implementation process of building energy saving measures in each case. Furthermore, a multi-scale analytical framework is employed to investigate relevant stakeholders that shape Shanghai's commercial building energy governance. Research findings and policy recommendations are offered at the close of this dissertation. Findings and policy recommendations are intended to facilitate commercial building energy governance in Shanghai and

Multiobjective optimisation of energy systems and building envelope retrofit in a residential community

International Nuclear Information System (INIS)

Wu, Raphael; Mavromatidis, Georgios; Orehounig, Kristina; Carmeliet, Jan

2017-01-01

Highlights: • Simultaneous optimisation of building envelope retrofit and energy systems. • Retrofit and energy systems change interact and should be considered simultaneously. • Case study quantifies cost-GHG emission tradeoffs for different retrofit options. - Abstract: In this paper, a method for a multi-objective and simultaneous optimisation of building energy systems and retrofit is presented. Tailored to be suitable for the diverse range of existing buildings in terms of age, size, and use, it combines dynamic energy demand simulation to explore individual retrofit scenarios with an energy hub optimisation. Implemented as an epsilon-constrained mixed integer linear program (MILP), the optimisation matches envelope retrofit with renewable and high efficiency energy supply technologies such as biomass boilers, heat pumps, photovoltaic and solar thermal panels to minimise life cycle cost and greenhouse gas (GHG) emissions. Due to its multi-objective, integrated assessment of building transformation options and its ability to capture both individual building characteristics and trends within a neighbourhood, this method is aimed to provide developers, neighbourhood and town policy makers with the necessary information to make adequate decisions. Our method is deployed in a case study of typical residential buildings in the Swiss village of Zernez, simulating energy demands in EnergyPlus and solving the optimisation problem with CPLEX. Although common trade-offs in energy system and retrofit choice can be observed, optimisation results suggest that the diversity in building age and size leads to optimal strategies for retrofitting and building system solutions, which are specific to different categories. With this method, GHG emissions of the entire community can be reduced by up to 76% at a cost increase of 3% compared to the current emission levels, if an optimised solution is selected for each building category.

BUILDING MECHATRONICS SIMULATION SYSTEM

OpenAIRE

HUSI Géza; SZÁSZ Csaba; HASHIMOTO Hideki; NIITSUMA Mihoko

2014-01-01

In international references a net zero-energy building (NZEB) is defined as a residential or commercial building with greatly reduced energy needs through efficiency gains such that the balance of energy needs can be supplied with renewable technologies. According to this general term definition, the essence of the concept is that by using low-cost and locally available nonpolluting sources, they generate energy onsite, in a quantity equal or greater than the total amo...

Locating room air-conditioners at floor level for energy saving in residential buildings

International Nuclear Information System (INIS)

Gao, C.F.; Lee, W.L.; Chen Hua

2009-01-01

Residential air-conditioning becomes a common feature in our daily life. They are typically installed at high level known as ceiling-based system (CAC). With the increasing use of floor-based air-conditioning system in commercial buildings for energy saving, it is proposed in this study to locate a top discharge/front return air-conditioner at floor level to resemble a floor-based air-conditioning system (FAC) to curb energy use in residential buildings. Given the concerns about draught discomfort and thermal stratification associated with floor-based air-conditioning systems, the objective of this study is to evaluate the air distribution performance and to quantify the possible energy benefits. Bedroom was chosen as a sensitive case for detailed air distribution performance evaluation. Experimental study, CFD simulations and energy simulations were conducted in achieving the specific objectives. CAC and FAC were installed in a bedroom-like environmental chamber for experimental study at different indoor and outdoor conditions. The air velocities and temperatures at various positions and levels inside the chamber were measured to determine the air distribution performance indices (ADPI) and airflow draft risk (DR). The cooling output, power consumption and coefficient of performance (COP) of the two units were measured and calculated for comparison. The experimental results show that ADPI of CAC and FAC are 92.3% and 84.6%, respectively. COP of FAC is 8.11% higher than CAC, and the corresponding DR are comparable. The experimental results were used to validate the CFD simulations as well as providing actual performance data for predicting the energy use of applying CAC and FAC in a case-study building. CFD simulations and draught assessment confirmed that there is no potential draught discomfort and thermal stratification associated with the use of FAC. Energy simulations predicted that the associated energy saving is 6.9%. Wider use of FAC in residential

Building envelope regulations on thermal comfort in glass facade buildings and energy-saving potential for PMV-based comfort control

Energy Technology Data Exchange (ETDEWEB)

Hwang, Ruey-Lung; Shu, Shiu-Ya [Department of Architecture, National United University, 1, Lien-Da, Kung-Ching Li, Miaoli, 36003 (China)

2011-04-15

This paper presents an investigation of the effect of building envelope regulation on thermal comfort and on the energy-saving potential for PMV-based comfort control in glass facade buildings. Occurrences and severity of overheating, based on the PMV-PPD model contained in ISO 7730, were used for the thermal comfort assessment. Parametric study simulations for an actual building with a large glass facade were carried out to predict the changes in thermal comfort levels in a space due to different glazing types, depths of overhang and glazing areas, which are the key parameters of the building envelope regulation index, named ENVLOAD, in Taiwan. The result demonstrates that the ENVLOAD has significant effect on thermal comfort. Additionally, comparative simulations between PMV-based comfort control and conventional thermostatic control were performed to investigate the changes in the energy-saving potential of a thermal comfort-controlled space due to changes of its ENVLOAD. The results demonstrate that the energy-saving potential in a PMV-based controlled space increases with low ENVLOAD conditions. (author)

Energy Flexibility in Retail Buildings

DEFF Research Database (Denmark)

Ma, Zheng; Billanes, Joy Dalmacio; Kjærgaard, Mikkel Baun

2017-01-01

Retail buildings has an important role for demand side energy flexibility because of their high energy consumption, variety of energy flexibility resources, and centralized control via building control systems. Energy flexibility requires agreements and collaborations among different actors......), with the discussion of the stakeholders’ roles and their interrelation in delivering energy flexibility with the influential factors to the actual implementation of energy flexible operation of their buildings. Based on a literature analysis, the results cover stakeholders’ types and roles, perceptions (drivers......, barriers, and benefits), energy management activities and technology adoptions, and the stakeholders’ interaction for the energy flexibility in retail buildings....

Assessment of infiltration heat recovery and its impact on energy consumption for residential buildings

International Nuclear Information System (INIS)

Solupe, Mikel; Krarti, Moncef

2014-01-01

Highlights: • Five steady-state air infiltration heat recovery or IHR models are described and compared. • IHR models are incorporated within whole-building simulation analysis tool. • IHR can reduce the thermal loads of residential buildings by 5–30%. - Abstract: Infiltration is a major contributor to the energy consumption of buildings, particularly in homes where it accounts for one-third of the heating and cooling loads. Traditionally, infiltration is calculated independent of the building envelope performance, however, it has been established that a thermal coupling exists between the infiltration and conduction heat transfer of the building envelope. This effect is known as infiltration heat recovery (IHR). Experiments have shown that infiltration heat recovery can typically reduce the infiltration thermal load by 10–20%. Currently, whole-building energy simulation tools do not account for the effect of infiltration heat recovery on heating and cooling loads. In this paper, five steady-state IHR models are described to account for the thermal interaction between infiltration air and building envelope components. In particular, inter-model and experimental comparisons are carried out to assess the prediction accuracy of five IHR models. In addition, the results from a series of sensitivity analyses are presented, including an evaluation of the predictions for heating energy use associated with four audited homes obtained from whole-building energy simulation analysis with implemented infiltration heat recovery models. Experimental comparison of the IHR models reveal that the predictions from all the five models are consistent and are within 2% when 1-D flow and heat transfer conditions are considered. When implementing IHR models to a whole-building simulation environment, a reduction of 5–30% in heating consumption is found for four audited residential homes

Simulated building energy demand biases resulting from the use of representative weather stations

Energy Technology Data Exchange (ETDEWEB)

Burleyson, Casey D.; Voisin, Nathalie; Taylor, Z. Todd; Xie, Yulong; Kraucunas, Ian

2018-01-01

Numerical building models are typically forced with weather data from a limited number of “representative cities” or weather stations representing different climate regions. The use of representative weather stations reduces computational costs, but often fails to capture spatial heterogeneity in weather that may be important for simulations aimed at understanding how building stocks respond to a changing climate. We quantify the potential reduction in bias from using an increasing number of weather stations over the western U.S. The approach is based on deriving temperature and load time series using incrementally more weather stations, ranging from 8 to roughly 150, to capture weather across different seasons. Using 8 stations, one from each climate zone, across the western U.S. results in an average absolute summertime temperature bias of 7.2°F with respect to a spatially-resolved gridded dataset. The mean absolute bias drops to 2.8°F using all available weather stations. Temperature biases of this magnitude could translate to absolute summertime mean simulated load biases as high as 13.8%, a significant error for capacity expansion planners who may use these types of simulations. Increasing the size of the domain over which biases are calculated reduces their magnitude as positive and negative biases may cancel out. Using 8 representative weather stations can lead to a 20-40% overestimation of peak building loads during both summer and winter. Using weather stations close to population centers reduces both mean and peak load biases. This approach could be used by others designing aggregate building simulations to understand the sensitivity to their choice of weather stations used to drive the models.

California commercial building energy benchmarking

Energy Technology Data Exchange (ETDEWEB)

Kinney, Satkartar; Piette, Mary Ann

2003-07-01

Building energy benchmarking is the comparison of whole-building energy use relative to a set of similar buildings. It provides a useful starting point for individual energy audits and for targeting buildings for energy-saving measures in multiple-site audits. Benchmarking is of interest and practical use to a number of groups. Energy service companies and performance contractors communicate energy savings potential with ''typical'' and ''best-practice'' benchmarks while control companies and utilities can provide direct tracking of energy use and combine data from multiple buildings. Benchmarking is also useful in the design stage of a new building or retrofit to determine if a design is relatively efficient. Energy managers and building owners have an ongoing interest in comparing energy performance to others. Large corporations, schools, and government agencies with numerous facilities also use benchmarking methods to compare their buildings to each other. The primary goal of Task 2.1.1 Web-based Benchmarking was the development of a web-based benchmarking tool, dubbed Cal-Arch, for benchmarking energy use in California commercial buildings. While there were several other benchmarking tools available to California consumers prior to the development of Cal-Arch, there were none that were based solely on California data. Most available benchmarking information, including the Energy Star performance rating, were developed using DOE's Commercial Building Energy Consumption Survey (CBECS), which does not provide state-level data. Each database and tool has advantages as well as limitations, such as the number of buildings and the coverage by type, climate regions and end uses. There is considerable commercial interest in benchmarking because it provides an inexpensive method of screening buildings for tune-ups and retrofits. However, private companies who collect and manage consumption data are concerned that the

Net Zero Energy Buildings

DEFF Research Database (Denmark)

Marszal, Anna Joanna; Bourrelle, Julien S.; Gustavsen, Arild

2010-01-01

and identify possible renewable energy supply options which may be considered in calculations. Finally, the gap between the methodology proposed by each organisation and their respective national building code is assessed; providing an overview of the possible changes building codes will need to undergo......The international cooperation project IEA SHC Task 40 / ECBCS Annex 52 “Towards Net Zero Energy Solar Buildings”, attempts to develop a common understanding and to set up the basis for an international definition framework of Net Zero Energy Buildings (Net ZEBs). The understanding of such buildings...

Computer simulations for state-of-the-art engineering design of a commercial building in Prague

NARCIS (Netherlands)

Bartak, M.; Drkal, F.; Hensen, J.L.M.; Lain, M.; Schwarzer, J.

2003-01-01

The paper describes the computer simulation work, which was carried out to support the engineering design team of the Luxembourg Plaza building development in Prague. The simulations for this study were based on (1) energy balance models covering the whole building for heating and cooling load

Optimal control of building storage systems using both ice storage and thermal mass – Part I: Simulation environment

International Nuclear Information System (INIS)

Hajiah, Ali; Krarti, Moncef

2012-01-01

Highlights: ► A simulation environment is described to account for both passive and active thermal energy storage (TES) systems. ► Laboratory testing results have been used to validate the predictions from the simulation environment. ► Optimal control strategies for TES systems have been developed as part of the simulation environment. - Abstract: This paper presents a simulation environment that can evaluate the benefits of using simultaneously building thermal capacitance and ice storage system to reduce total operating costs including energy and demand charges while maintaining adequate occupant comfort conditions within commercial buildings. The building thermal storage is controlled through pre-cooling strategies by setting space indoor air temperatures. The ice storage system is controlled by charging the ice tank and operating the chiller during low electrical charge periods and melting the ice during on-peak periods. Optimal controls for both building thermal storage and ice storage are developed to minimize energy charges, demand charges, or combined energy and demand charges. The results obtained from the simulation environment are validated using laboratory testing for an optimal controller.

A study on building performance analysis for energy retrofit of existing industrial facilities

International Nuclear Information System (INIS)

Gourlis, Georgios; Kovacic, Iva

2016-01-01

Highlights: • Thermal simulation of a historical industrial hall with limited data availability. • Considering waste heat from machinery after measuring production fluctuations. • Test of retrofit alternatives for roof and skylights. • Results indicate a significant reduction in heating energy demand up to 52%. • After retrofit naturally ventilated hall can achieve thermal comfort in summer. - Abstract: Due to the strengthening of regulations and codes on building energy performance, as well as with the application of national legislations regarding energy management and efficiency, existing industrial facilities are using thermal refurbishment and renovation as impetus for increasing their overall energy efficiency. This paper analyzes a building envelope refurbishment for a case study of an existing historical industrial facility. Critical parameters affecting energy performance of industrial buildings were identified by reviewing relevant literate. Two retrofit scenarios were developed and dynamic thermal simulation using EnergyPlus was implemented to evaluate the potential for improvement. Thereby the impact of interior loads was considered, determined by measurements conducted on factory machines, occupancy and lighting operation patterns. However, information regarding constructions of the existing facility and installed technical building services is limited. There is also uncertainty in the quantification of natural ventilation air change rate for such buildings. To overcome these limitations a study of various material databases was carried out, in order to assess data for building envelope composition. Input values for missing data were provided based on literature, allowing a fair comparison between refurbishment alternatives. Simulation results showed that the heating demand of the facility could be reduced up to 52%, indicating a significant potential for energy savings. Beyond that, thermal performance against summer overheating also

A fresh look at weather impact on peak electricity demand and energy use of buildings using 30-year actual weather data

International Nuclear Information System (INIS)

Hong, Tianzhen; Chang, Wen-Kuei; Lin, Hung-Wen

2013-01-01

Highlights: • Weather has a significant impact on both the peak electricity demand and energy use. • Weather impact varies with building type, building efficiency level, and location. • Simulated results using TMY3 weather data can under or over estimate those of AMY. • It is crucial to assess performance of buildings using long-term actual weather data. • Findings enable building stakeholders to make better decisions on weather impact. - Abstract: Buildings consume more than one third of the world’s total primary energy. Weather plays a unique and significant role as it directly affects the thermal loads and thus energy performance of buildings. The traditional simulated energy performance using Typical Meteorological Year (TMY) weather data represents the building performance for a typical year, but not necessarily the average or typical long-term performance as buildings with different energy systems and designs respond differently to weather changes. Furthermore, the single-year TMY simulations do not provide a range of results that capture yearly variations due to changing weather, which is important for building energy management, and for performing risk assessments of energy efficiency investments. This paper employs large-scale building simulation (a total of 3162 runs) to study the weather impact on peak electricity demand and energy use with the 30-year (1980–2009) Actual Meteorological Year (AMY) weather data for three types of office buildings at two design efficiency levels, across all 17 ASHRAE climate zones. The simulated results using the AMY data are compared to those from the TMY3 data to determine and analyze the differences. Besides further demonstration, as done by other studies, that actual weather has a significant impact on both the peak electricity demand and energy use of buildings, the main findings from the current study include: (1) annual weather variation has a greater impact on the peak electricity demand than it does

Solar Assisted Ground Source Heat Pump Performance in Nearly Zero Energy Building in Baltic Countries

Science.gov (United States)

Januševičius, Karolis; Streckienė, Giedrė

2013-12-01

In near zero energy buildings (NZEB) built in Baltic countries, heat production systems meet the challenge of large share domestic hot water demand and high required heating capacity. Due to passive solar design, cooling demand in residential buildings also needs an assessment and solution. Heat pump systems are a widespread solution to reduce energy use. A combination of heat pump and solar thermal collectors helps to meet standard requirements and increases the share of renewable energy use in total energy balance of country. The presented paper describes a simulation study of solar assisted heat pump systems carried out in TRNSYS. The purpose of this simulation was to investigate how the performance of a solar assisted heat pump combination varies in near zero energy building. Results of three systems were compared to autonomous (independent) systems simulated performance. Different solar assisted heat pump design solutions with serial and parallel solar thermal collector connections to the heat pump loop were modelled and a passive cooling possibility was assessed. Simulations were performed for three Baltic countries: Lithuania, Latvia and Estonia.

Impact of Moistened Bio-insulation on Whole Building Energy Use

Directory of Open Access Journals (Sweden)

Latif Eshrar

2017-01-01

Full Text Available One of the key properties of hemp insulation is its moisture adsorption capacity. Adsorption of moisture can increase both thermal conductivity and heat capacity of the insulation. The current study focuses on the effect of moisture induced thermal mass of installed hemp insulation on the whole building energy use. Hygrothermal and thermal simulations were performed using the CIBSE TRY weather data of Edinburgh and Birmingham with the aid of following simulation tools: WUFI and IES. Following simplified building types were considered: building-1 with dry hemp wall and loft insulations, building-2 with moistened hemp wall and loft insulation and building-3 with stone wool insulation. It was observed that the overall conditioning load of building-1 was 1.2 to 2.3% higher than building-2 and 3. However, during the summer season, the cooling load of building-2 was 3-7.5% lower than the other buildings. It implies that, moistened insulation can potentially mitigate the effect of increasing cooling degree days induced by global warming.

75 FR 20833 - Building Energy Codes

Science.gov (United States)

2010-04-21

...-0012] Building Energy Codes AGENCY: Office of Energy Efficiency and Renewable Energy, Department of... the current model building energy codes or their equivalent. DOE is interested in better understanding... codes, Standard 90.1-2007, Energy Standard for Buildings Except Low-Rise Residential Buildings (or...

Comparative Validation of Building Simulation Software

DEFF Research Database (Denmark)

Kalyanova, Olena; Heiselberg, Per

The scope of this subtask is to perform a comparative validation of the building simulation software for the buildings with the double skin façade. The outline of the results in the comparative validation identifies the areas where is no correspondence achieved, i.e. calculation of the air flow r...... is that the comparative validation can be regarded as the main argument to continue the validation of the building simulation software for the buildings with the double skin façade with the empirical validation test cases.......The scope of this subtask is to perform a comparative validation of the building simulation software for the buildings with the double skin façade. The outline of the results in the comparative validation identifies the areas where is no correspondence achieved, i.e. calculation of the air flow...

A Fresh Look at Weather Impact on Peak Electricity Demand and Energy Use of Buildings Using 30-Year Actual Weather Data

Energy Technology Data Exchange (ETDEWEB)

Hong, Tianzhen; Chang, Wen-Kuei; Lin, Hung-Wen

2013-05-01

Buildings consume more than one third of the world?s total primary energy. Weather plays a unique and significant role as it directly affects the thermal loads and thus energy performance of buildings. The traditional simulated energy performance using Typical Meteorological Year (TMY) weather data represents the building performance for a typical year, but not necessarily the average or typical long-term performance as buildings with different energy systems and designs respond differently to weather changes. Furthermore, the single-year TMY simulations do not provide a range of results that capture yearly variations due to changing weather, which is important for building energy management, and for performing risk assessments of energy efficiency investments. This paper employs large-scale building simulation (a total of 3162 runs) to study the weather impact on peak electricity demand and energy use with the 30-year (1980 to 2009) Actual Meteorological Year (AMY) weather data for three types of office buildings at two design efficiency levels, across all 17 ASHRAE climate zones. The simulated results using the AMY data are compared to those from the TMY3 data to determine and analyze the differences. Besides further demonstration, as done by other studies, that actual weather has a significant impact on both the peak electricity demand and energy use of buildings, the main findings from the current study include: 1) annual weather variation has a greater impact on the peak electricity demand than it does on energy use in buildings; 2) the simulated energy use using the TMY3 weather data is not necessarily representative of the average energy use over a long period, and the TMY3 results can be significantly higher or lower than those from the AMY data; 3) the weather impact is greater for buildings in colder climates than warmer climates; 4) the weather impact on the medium-sized office building was the greatest, followed by the large office and then the small

Energy Efficiency Requirements in Building Codes, Energy Efficiency Policies for New Buildings. IEA Information Paper

Energy Technology Data Exchange (ETDEWEB)

Laustsen, Jens

2008-03-15

The aim of this paper is to describe and analyse current approaches to encourage energy efficiency in building codes for new buildings. Based on this analysis the paper enumerates policy recommendations for enhancing how energy efficiency is addressed in building codes and other policies for new buildings. This paper forms part of the IEA work for the G8 Gleneagles Plan of Action. These recommendations reflect the study of different policy options for increasing energy efficiency in new buildings and examination of other energy efficiency requirements in standards or building codes, such as energy efficiency requirements by major renovation or refurbishment. In many countries, energy efficiency of buildings falls under the jurisdiction of the federal states. Different standards cover different regions or climatic conditions and different types of buildings, such as residential or simple buildings, commercial buildings and more complicated high-rise buildings. There are many different building codes in the world and the intention of this paper is not to cover all codes on each level in all countries. Instead, the paper details different regions of the world and different ways of standards. In this paper we also evaluate good practices based on local traditions. This project does not seek to identify one best practice amongst the building codes and standards. Instead, different types of codes and different parts of the regulation have been illustrated together with examples on how they have been successfully addressed. To complement this discussion of efficiency standards, this study illustrates how energy efficiency can be improved through such initiatives as efficiency labelling or certification, very best practice buildings with extremely low- or no-energy consumption and other policies to raise buildings' energy efficiency beyond minimum requirements. When referring to the energy saving potentials for buildings, this study uses the analysis of recent IEA

IEA Energy Training Capacity-building Programme

Energy Technology Data Exchange (ETDEWEB)

NONE

2009-07-01

The IEA has carried out training activities in energy-related areas from its origins as an agency, with the Emergency Response Exercises (ERE), designed to prepare member countries for oil supply disruption through a set of specially prepared drills simulating crisis conditions. The globalisation of world energy markets in recent years and the wider engagement of the IEA beyond its members have expanded this role, as demand for training instruction has increased. In response, the IEA has created the Energy Training and Capacity-Building Programme, which, through seminars and workshops, secondments and internships, will offer training in the methods and standards that make IEA work in a wide range of energy-related areas, including statistics, the international standard for objective policy recommendations.

Energy Efficiency, Building Productivity and the Commercial Buildings Market

Energy Technology Data Exchange (ETDEWEB)

Jones, D.W.

2002-05-16

The energy-efficiency gap literature suggests that building buyers are often short-sighted in their failure to apply life-cycle costing principles to energy efficient building technologies, with the result that under investment in these advanced technology occurs. This study examines the reasons this behavior may occur, by analyzing the pressures that market forces place on purchasers of buildings. Our basic conclusion is that the fundamental manner in which the buildings sector does business creates pressures to reduce initial capital outlays and to hedge against a variety of risks, including the ability of building owners to capture benefits from energy efficiency. Starting from the position that building buyers' willingness to pay drives choices over building attributes, we examine basic market principles, the structure of the buildings market, including the role of lenders, and policies that promote penetration of energy efficient technologies. We conclude that greater attention to buyers, and to the incentives and constraints they face, would promote a better understanding of building investment choices and contribute to better policies to promote the penetration of these technologies into markets.

Life Cycle Multi-Criteria Analysis Of Alternative Energy Supply Systems For A Residential Building

Directory of Open Access Journals (Sweden)

Artur Rogoža

2013-12-01

Full Text Available The article analyses energy supply alternatives for a partially renovated residential building. In addition to the existing district heating (base case alternative systems, gas boilers, heat pumps (air-water and ground-water, solar collectors, solar cells, and combinations of these systems have been examined. Actual heat consumption of the building and electricity demand determined by the statistical method are used for simulating the systems. The process of simulation is performed using EnergyPro software. In order to select an optimal energy supply option, the life cycle analysis of all systems has been carried out throughout a life span of the building, and the estimated results of energy, environmental and economic evaluation have been converted into non-dimensional variables (3E using multi–criteria analysis.Article in Lithuanian

Development of a Mobile Application for Building Energy Prediction Using Performance Prediction Model

Directory of Open Access Journals (Sweden)

Yu-Ri Kim

2016-03-01

Full Text Available Recently, the Korean government has enforced disclosure of building energy performance, so that such information can help owners and prospective buyers to make suitable investment plans. Such a building energy performance policy of the government makes it mandatory for the building owners to obtain engineering audits and thereby evaluate the energy performance levels of their buildings. However, to calculate energy performance levels (i.e., asset rating methodology, a qualified expert needs to have access to at least the full project documentation and/or conduct an on-site inspection of the buildings. Energy performance certification costs a lot of time and money. Moreover, the database of certified buildings is still actually quite small. A need, therefore, is increasing for a simplified and user-friendly energy performance prediction tool for non-specialists. Also, a database which allows building owners and users to compare best practices is required. In this regard, the current study developed a simplified performance prediction model through experimental design, energy simulations and ANOVA (analysis of variance. Furthermore, using the new prediction model, a related mobile application was also developed.

Demand and Supply Side Management Strategies for Zero Energy Buildings

DEFF Research Database (Denmark)

Ghiasi, Mohammad Iman; Hajizadeh, Amin; Aliakbar Golkar, Masoud

2017-01-01

operational scenarios. Afterwards, the SSM strategy based on adaptive fuzzy control is proposed to control of power flow between hybrid renewable sources and PEVs of the main building for a short time interval. Moreover, an fuzzy sliding power control strategy for the controlling of battery energy storage...... is introduced to keep the balance between the requested power from building, PEV and output power of hybrid power generation resources. Simulation and experimental results are presented to validate the capability of the proposed power and energy flow control strategy....

Assessing the Needs and Gaps of Building Information Technologies for Energy Retrofit of Historic Buildings in the Korean Context

Directory of Open Access Journals (Sweden)

Sean Hay Kim

2018-04-01

Full Text Available Most domestic modern buildings from the early 1900s have been constructed as heavy mass, and for many years have relied on passive measures for climate control. Since effective passive measures eventually reduce the heating and cooling loads, thus also reducing the system size, passive and hybrid measures are the most preferred Energy Conservation Measures (ECMs. In addition, the domestic situation and climate are additional constraints in energy retrofit decision making, such as a shorter budget and time, poor maintenance history, and uncertainties in vernacular lifestyle. For this reason, the performance improvement and side-effects prior to installing ECMs should be predictable, particularly in case the originality can be damaged. This complexity confirms that simulation-based Measurement and Verification (M&V would better suit the energy retrofit of domestic historic buildings. However, many domestic investors still believe re-construction has a larger economic value than restoration. Therefore, they are even unwilling to invest in more time than a preset audit period—typically less than a week. Although simulation-based M&V is theoretically favored for retrofit decision making, its process including collecting data, modeling and analysis, and evaluating and designing ECMs could still be too demanding to domestic practitioners. While some manual, repetitive, error-prone works exist in the conventional retrofit process and simulation-based M&V, it is proposed here that enhanced Building Information Technology (BIT is able to simplify, automate, and objectify, at least the critical steps of the retrofit project. The aim of this study is to find an efficient and effective energy retrofit strategy for domestic historic buildings that appeals to both domestic investors and practitioners by testing selective BIT tools on an actual historic building. This study concludes with the suggestion that software vendors are asked to develop enhanced

Energy retrofit of commercial buildings. Case study and applied methodology

Energy Technology Data Exchange (ETDEWEB)

Aste, N.; Del Pero, C. [Department of Building Environment Science and Technology (BEST), Politecnico di Milano, Via Bonardi 3, 20133 Milan (Italy)

2013-05-15

Commercial buildings are responsible for a significant share of the energy requirements of European Union countries. Related consumptions due to heating, cooling, and lighting appear, in most cases, very high and expensive. Since the real estate is renewed with a very small percentage each year and current trends suggest reusing the old structures, strategies for improving energy efficiency and sustainability should focus not only on new buildings, but also and especially on existing ones. Architectural renovation of existing buildings could provide an opportunity to enhance their energy efficiency, by working on the improvement of envelopes and energy supply systems. It has also to be noted that the measures aimed to improve the energy performance of buildings should pay particular attention to the cost-effectiveness of the interventions. In general, there is a lack of well-established methods for retrofitting, but if a case study achieves effective results, the adopted strategies and methodologies can be successfully replicated for similar kinds of buildings. In this paper, an iterative methodology for energy retrofit of commercial buildings is presented, together with a specific application on an existing office building. The case study is particularly significant as it is placed in an urban climatic context characterized by cold winters and hot summers; consequently, HVAC energy consumption is considerable throughout the year. The analysis and simulations of energy performance before and after the intervention, along with measured data on real energy performance, demonstrate the validity of the applied approach. The specifically developed design and refurbishment methodology, presented in this work, could be also assumed as a reference in similar operations.

The utilization of the storage of thermal energy in buildings. Underground heat storages - thermic simulation and profitability; Termisen energian varastoinnin hyvaeksikaeyttoemahdollisuudet rakennusten laemmityksessae ja jaeaehdytyksessae. Maanalaiset varastot - laempoetekninen simulointi ja taloudellinen kannattavuus

Energy Technology Data Exchange (ETDEWEB)

Suokas, M.; Heinonen, J.; Karola, A.; Laine, T.; Siren, K.

1998-12-31

Interest in different sources of free energy has significantly increased due to the possibility to decrease the consumption of fossil fuels and nuclear power. This can be reached, for example, with waste heat recovery and by utilising natural heat and cool energy sources. The main problem is that the supply and use of energy do not encounter and this causes a need for thermal energy storage. The earlier heat storage systems have utilised compressor heat pumps because the temperature levels of heat storages are not high enough for the ordinary heating and cooling systems. The disadvantage is the complexity of these systems which leads to increasing building costs. Therefore, this study deals with systems of low temperature levels used mainly for cooling purposes. The aim was to find out their usability, savings and profitability. The function and energy consumption of systems were simulated with models of buildings, soil heat storage and climate. The soil model simulates heat dynamic behaviour of the masses of soil. With the climate model it was possible to simulate transient heat losses of the storage and building. It was also possible to simulate various climatic conditions by changing input data of the climate model. In the simulated systems the emphasis is on the production of cooling energy by utilising the low temperature of the ground. The systems consist of heat storage and building. The cooling energy will be charged in winter to the storage when the heat energy charged in summer will be transferred to the supply air of ventilating unit. After the energy simulations the investment and usage costs of this kind of systems were compared with costs of ordinary compressor cooling systems. The buildings studied were an imaginary LVIS 2000 office building and the Messukeskus in Helsinki which is a large hall built for exhibitions. The types of soil were wet clay and granite. The LVIS 2000 office building needs a rock heat storage with capacity of 8 000-30 000 m

Cool roofs in China: Policy review, building simulations, and proof-of-concept experiments

International Nuclear Information System (INIS)

Gao, Yafeng; Xu, Jiangmin; Yang, Shichao; Tang, Xiaomin; Zhou, Quan; Ge, Jing; Xu, Tengfang; Levinson, Ronnen

2014-01-01

While the concept of reflective roofing is not new to China, most Chinese cool roof research has taken place within the past decade. Some national and local Chinese building energy efficiency standards credit or recommend, but do not require, cool roofs or walls. EnergyPlus simulations of standard-compliant Chinese office and residential building prototypes in seven Chinese cities (Harbin, Changchun, Beijing, Chongqing, Shanghai, Wuhan, and Guangzhou) showed that substituting an aged white roof (albedo 0.6) for an aged gray roof (albedo 0.2) yields positive annual load, energy, energy cost, CO 2 , NO x , and SO 2 savings in all hot-summer cities (Chongqing, Shanghai, Wuhan, and Guangzhou). Measurements in an office building in Chongqing in August 2012 found that a white coating lowered roof surface temperature by about 20 °C, and reduced daily air conditioning energy use by about 9%. Measurements in a naturally ventilated factory in Guangdong Province in August 2011 showed that a white coating decreased roof surface temperature by about 17 °C, lowered room air temperature by 1–3 °C, and reduced daily roof heat flux by 66%. Simulation and experimental results suggest that cool roofs should be credited or prescribed in building energy efficiency standards for both hot summer/warm winter and hot summer/cold winter climates in China

Energy Innovations for Healthy Buildings

Energy Technology Data Exchange (ETDEWEB)

Bogucz, Edward A. [Syracuse Univ., NY (United States)

2016-09-23

Healthy buildings provide high indoor environmental quality for occupants while simultaneously reducing energy consumption. This project advanced the development and marketability of envisioned healthy, energy-efficient buildings through studies that evaluated the use of emerging technologies in commercial and residential buildings. The project also provided resources required for homebuilders to participate in DOE’s Builders Challenge, concomitant with the goal to reduce energy consumption in homes by at least 30% as a first step toward achieving envisioned widespread availability of net-zero energy homes by 2030. In addition, the project included outreach and education concerning energy efficiency in buildings.

Energy efficiency buildings program, FY 1980

Energy Technology Data Exchange (ETDEWEB)

1981-05-01

A separate abstract was prepared on research progress in each group at LBL in the energy efficient buildings program. Two separate abstracts were prepared for the Windows and Lighting Program. Abstracts prepared on other programs are: Energy Performance of Buildings; Building Ventilation and Indoor Air Quality Program; DOE-21 Building Energy Analysis; and Building Energy Data Compilation, Analysis, and Demonstration. (MCW)

Building energy efficiency in rural China

International Nuclear Information System (INIS)

Evans, Meredydd; Yu, Sha; Song, Bo; Deng, Qinqin; Liu, Jing; Delgado, Alison

2014-01-01

Rural buildings in China now account for more than half of China's total building energy use. Forty percent of the floorspace in China is in rural villages and towns. Most of these buildings are very energy inefficient, and may struggle to provide for basic needs. They are cold in the winter, and often experience indoor air pollution from fuel use. The Chinese government plans to adopt a voluntary building energy code, or design standard, for rural homes. The goal is to build on China's success with codes in urban areas to improve efficiency and comfort in rural homes. The Chinese government recognizes rural buildings represent a major opportunity for improving national building energy efficiency. The challenges of rural China are also greater than those of urban areas in many ways because of the limited local capacity and low income levels. The Chinese government wants to expand on new programs to subsidize energy efficiency improvements in rural homes to build capacity for larger-scale improvement. This article summarizes the trends and status of rural building energy use in China. It then provides an overview of the new rural building design standard, and describes options and issues to move forward with implementation. - Highlights: • Building energy use is larger in rural China than in cities. • Rural buildings are very energy intensive, and energy use is growing with incomes. • A new design standard aims to help rural communities build more efficiently. • Important challenges remain with implementation

Simulation of Solar Energy Use in Livelihood of Buildings

Science.gov (United States)

Lvocich, I. Ya; Preobrazhenskiy, A. P.; Choporov, O. N.

2017-11-01

Solar energy can be considered as the most technological and economical type of renewable energy. The purpose of the paper is to increase the efficiency of solar energy utilization on the basis of the mathematical simulation of the solar collector. A mathematical model of the radiant heat transfer vacuum solar collector is clarified. The model was based on the process of radiative heat transfer between glass and copper walls with the defined blackness degrees. A mathematical model of the ether phase transition point is developed. The dependence of the reservoir walls temperature change on the ambient temperature over time is obtained. The results of the paper can be useful for the development of prospective sources using solar energy.

On the Evaluation of Solar Greenhouse Efficiency in Building Simulation during the Heating Period

Directory of Open Access Journals (Sweden)

Francesco Asdrubali

2012-06-01

Full Text Available Among solar passive systems integrated in buildings, sunspaces or solar greenhouses represent a very interesting solution. A sunspace is a closed, southbound volume, constituted by transparent surfaces, adjacent to a building, which reduces winter energy demand thanks to the use of solar gains. The effect of a typical solar greenhouse on the energy balance of a building was evaluated during the heating period with two stationary procedures (Method 5000 and EN ISO 13790 and with a dynamic tool (TRNSYS. After the analysis of the greenhouse alone, the behavior of an entire house was simulated; a flat equipped with a sunspace, recently built thanks to public contributions provided by the Umbria Region in Italy to widespread bio-climatic architecture, was used as case-study. Simulations were carried out for the examined flat, both with a steady-state tool and with a dynamic one; the contribution of the sunspace was estimated thanks to the various methods previously mentioned. Finally, the simulated data were satisfactorily compared with the real energy consumptions (natural gas for heating of the flat; the sunspace allows a reduction of winter energy demand of the flat of about 20%.

Analysis of impact of daylight time savings on energy use of buildings in Kuwait

Energy Technology Data Exchange (ETDEWEB)

Krarti, Moncef, E-mail: moncef.krarti@colorado.ed [CEAE Department, CB 428, University of Colorado, Boulder, CO 80309 (United States); Hajiah, Ali [Kuwait Institute for Scientific Research, Safat (Kuwait)

2011-05-15

In this paper, a detailed simulation-based analysis is conducted to assess the impact of adopting Daylight Saving Time (DST) on the electrical energy use and peak demand in Kuwait. The analysis focused on the impact of DST in the building sector since it represents 90% of electrical energy usage of Kuwait. The simulation results indicate that the adoption of DST has mixed impacts for Kuwait. While the commercial and the governmental sectors may benefit from the DST, the private residences and apartment buildings can see both their annual energy use and peak demand increase slightly by adopting DST. The overall impact of the DST implementation is rather minimal with a slight increase energy use of about 0.07% and a slight reduction in peak demand of 0.14% or about 12 MW based on 2005 electrical peak demand for Kuwait. - Research highlights: {yields} A detailed simulation-based analysis is conducted to assess the impact of adopting Daylight Saving Time (DST) on the electrical energy use and peak demand in Kuwait. {yields} The analysis focused on the impact of DST in the building sector since it represents 90% of electrical energy usage of Kuwait. {yields} It is found that while the commercial and the governmental building sectors may benefit from DST, the private residences and apartment buildings can see both their annual energy use and peak demand increase slightly by adopting DST. {yields} Since the residential sector represents the majority of the electrical load in Kuwait, DST adoption was found to cause slight increase in annual electrical energy use by about 0.07% and a slight reduction in electrical peak electrical demand by about 0.14%.

Analysis of impact of daylight time savings on energy use of buildings in Kuwait

International Nuclear Information System (INIS)

Krarti, Moncef; Hajiah, Ali

2011-01-01

In this paper, a detailed simulation-based analysis is conducted to assess the impact of adopting Daylight Saving Time (DST) on the electrical energy use and peak demand in Kuwait. The analysis focused on the impact of DST in the building sector since it represents 90% of electrical energy usage of Kuwait. The simulation results indicate that the adoption of DST has mixed impacts for Kuwait. While the commercial and the governmental sectors may benefit from the DST, the private residences and apartment buildings can see both their annual energy use and peak demand increase slightly by adopting DST. The overall impact of the DST implementation is rather minimal with a slight increase energy use of about 0.07% and a slight reduction in peak demand of 0.14% or about 12 MW based on 2005 electrical peak demand for Kuwait. - Research highlights: → A detailed simulation-based analysis is conducted to assess the impact of adopting Daylight Saving Time (DST) on the electrical energy use and peak demand in Kuwait. → The analysis focused on the impact of DST in the building sector since it represents 90% of electrical energy usage of Kuwait. → It is found that while the commercial and the governmental building sectors may benefit from DST, the private residences and apartment buildings can see both their annual energy use and peak demand increase slightly by adopting DST. → Since the residential sector represents the majority of the electrical load in Kuwait, DST adoption was found to cause slight increase in annual electrical energy use by about 0.07% and a slight reduction in electrical peak electrical demand by about 0.14%.

Energy audit role in building planning

Science.gov (United States)

Sipahutar, Riman; Bizzy, Irwin

2017-11-01

An energy audit is one way to overcome the excessive use of energy in buildings. The increasing growth of population, economy, and industry will have an impact on energy demand and the formation of greenhouse gas emissions. Indonesian National Standard (SNI) concerning the building has not been implemented optimally due to the socialization process by a government not yet been conducted. An energy audit of buildings has been carried out at offices and public services. Most electrical energy in buildings used for air refresher equipment or air conditioning. Calculation of OTTV has demonstrated the importance of performing since the beginning of the planning of a building to get energy-efficient buildings.

Actual building energy use patterns and their implications for predictive modeling

International Nuclear Information System (INIS)

Heidarinejad, Mohammad; Cedeño-Laurent, Jose G.; Wentz, Joshua R.; Rekstad, Nicholas M.; Spengler, John D.; Srebric, Jelena

2017-01-01

Highlights: • Developed three building categories based on energy use patterns of campus buildings. • Evaluated implication of temporal energy data granularity on predictive modeling. • Demonstrated importance of monitoring daily chilled water consumption. • Identified interval electricity data as an indicator of building operation schedules. • Demonstrated a calibration process for energy modeling of a campus building. - Abstract: The main goal of this study is to understand the patterns in which commercial buildings consume energy, rather than evaluating building energy use based on aggregate utility bills typically linked to building principal tenant activity or occupancy type. The energy consumption patterns define buildings as externally-load, internally-load, or mixed-load dominated buildings. Penn State and Harvard campuses serve as case studies for this particular research project. The buildings in these two campuses use steam, chilled water, and electricity as energy commodities and maintain databases of different resolutions to include minute, hourly, daily, and monthly data instances depending on the commodity and available data acquisition system. The results of this study show monthly steam consumption directly correlates to outdoor environmental conditions for 88% of the studied buildings, while chilled water consumption has negligible correlation to the outdoor environmental conditions. Thus, in terms of monthly chilled water consumption, 86% of buildings are internally-load and mixed-load dominated, respectively. Chilled water consumption is better suited for the daily analyses compared to the monthly and hourly analyses. While the influence of building operation schedules affects the analyses at the hourly level, the monthly chilled water consumptions are not good indicators of the building energy consumption patterns. Electricity consumption at the monthly (or seasonal) level can support the building energy simulation tools for the

Consumer Central Energy Flexibility in Office Buildings

DEFF Research Database (Denmark)

Billanes, Joy Dalmacio; Ma, Zheng; Jørgensen, Bo Nørregaard

2017-01-01

Energy flexibility in buildings will play an important role in the smart energy system. Office buildings have more potentials to provide energy flexibility to the grid compared to other types of buildings, due to the existing building management, control systems and large energy consumption....... Consumers in office buildings (building owners/managers and occupants) take a main role for adopting and engaging in building energy flexibility. In this paper provides a systematic review of consumer central energy flexibility in office buildings with the discussion of social, technical and business...... can boost energy flexibility in the office buildings....

Locating room air-conditioners at floor level for energy saving in residential buildings

Energy Technology Data Exchange (ETDEWEB)

Gao, C.F.; Lee, Hua; Chen, W.L. [Department of Building Services Engineering, Hong Kong Polytechnic University, Hung Hom (China)

2009-08-15

Residential air-conditioning becomes a common feature in our daily life. They are typically installed at high level known as ceiling-based system (CAC). With the increasing use of floor-based air-conditioning system in commercial buildings for energy saving, it is proposed in this study to locate a top discharge/front return air-conditioner at floor level to resemble a floor-based air-conditioning system (FAC) to curb energy use in residential buildings. Given the concerns about draught discomfort and thermal stratification associated with floor-based air-conditioning systems, the objective of this study is to evaluate the air distribution performance and to quantify the possible energy benefits. Bedroom was chosen as a sensitive case for detailed air distribution performance evaluation. Experimental study, CFD simulations and energy simulations were conducted in achieving the specific objectives. CAC and FAC were installed in a bedroom-like environmental chamber for experimental study at different indoor and outdoor conditions. The air velocities and temperatures at various positions and levels inside the chamber were measured to determine the air distribution performance indices (ADPI) and airflow draft risk (DR). The cooling output, power consumption and coefficient of performance (COP) of the two units were measured and calculated for comparison. The experimental results show that ADPI of CAC and FAC are 92.3% and 84.6%, respectively. COP of FAC is 8.11% higher than CAC, and the corresponding DR are comparable. The experimental results were used to validate the CFD simulations as well as providing actual performance data for predicting the energy use of applying CAC and FAC in a case-study building. CFD simulations and draught assessment confirmed that there is no potential draught discomfort and thermal stratification associated with the use of FAC. Energy simulations predicted that the associated energy saving is 6.9%. Wider use of FAC in residential

An Innovative Enhanced Wall to Reduce the Energy Demand in Buildings

Science.gov (United States)

Fantozzi, F.; Filipeschi, S.; Mameli, M.; Nesi, S.; Cillari, G.; Mantelli, M. B. H.; Milanez, F. H.

2017-01-01

Energy saving in buildings is one of most important issues for European countries. Although in the last years many studies have been carried out in order to reach the zero-consumption house the energy rate due to passive solar heating could be further enhanced. This paper proposes a method for increasing the energy rate absorbed by opaque walls by using a two phase loop thermosyphon connecting the internal and the external façade of a prefabricated house wall. The evaporator zone is embedded into the outside facade and the condenser is indoor placed to heat the domestic environment. The thermosyphon has been preliminary designed and implanted into a wall for a prefabricated house in Italy. An original dynamic thermal model of the building equipped with the thermosyphon wall allowed the evolution of the indoor temperature over time and the energy saving rates. The transient behaviour of the building has been simulated during the winter period by using the EnergyPlusTM software. The annual saving on the heating energy is higher than 50% in the case of a low consumption building.

Whole-building Hygrothermal Simulation Model

DEFF Research Database (Denmark)

Rode, Carsten; Grau, Karl

2003-01-01

An existing integrated simulation tool for dynamic thermal simulation of building was extended with a transient model for moisture release and uptake in building materials. Validation of the new model was begun with comparison against measurements in an outdoor test cell furnished with single...... materials. Almost quasi-steady, cyclic experiments were used to compare the indoor humidity variation and the numerical results of the integrated simulation tool with the new moisture model. Except for the case with chipboard as furnishing, the predictions of indoor humidity with the detailed model were...

Energy-efficient window systems. Effects on energy use and daylight in buildings

Energy Technology Data Exchange (ETDEWEB)

Buelow-Huebe, H.

2001-11-01

This thesis deals with energy-efficient windows in Swedish buildings. Parametric studies were performed in the dynamic energy simulation tool Derob-LTH in order to study the effects of window choices on energy use and indoor climate for both residential and office buildings. A steady-state program was used to evaluate two years of measurements of energy use and indoor temperatures of an energy-efficient row-house. Two behavioural studies regarding (1) daylight transmittance, view and room perception using super-insulated windows and (2) the satisfaction with the daylight environment and the use of shading devices in response to daylight/sunlight were conducted in full-scale laboratory environments exposed to the natural climate. Results show that as the energy-efficiency of buildings increase, window U-values must decrease in order not to increase the annual heating demand, since the heating season is shortened, and useful solar gains become smaller. For single-family houses with a window-to-floor area ratio of 15 % and insulated according the current Swedish building code, the U-values should thus on average be lower than 1.0 W/m{sup 2}K. For houses insulated according to 1960s standard, the U-value may on average be 1.6 W/m{sup 2}K. For colder climates (northern Sweden), the U-values should be somewhat lower, while slightly higher U-values can be tolerated in milder climates of south Sweden. Thermal comfort during winter is improved for energy-efficient windows. However, overheating problems exist for both super-insulated houses and highly glazed office buildings showing a need for very low U-values in combination with low g-values. Daylight experiments indicate that the use of two low-emittance coatings tints the transmitted daylight enough to be appreciated, and colours may be perceived as more drab and rooms more enclosed. A compromise between energy-efficiency and daylighting may be needed, and it is suggested that only one coating be used except when very

Building energy, building leadership : recommendations for the adoption, development, and implementation of a commercial building energy code in Manitoba

Energy Technology Data Exchange (ETDEWEB)

Akerstream, T. [Manitoba Hydro, Winnipeg, MB (Canada); Allard, K. [City of Thompson, Thompson, MB (Canada); Anderson, N.; Beacham, D. [Manitoba Office of the Fire Commissioner, Winnipeg, MB (Canada); Andrich, R. [The Forks North Portage Partnership, MB (Canada); Auger, A. [Natural Resources Canada, Ottawa, ON (Canada). Office of Energy Efficiency; Downs, R.G. [Shindico Realty Inc., Winnipeg, MB (Canada); Eastwood, R. [Number Ten Architectural Group, Winnipeg, MB (Canada); Hewitt, C. [SMS Engineering Ltd., Winnipeg, MB (Canada); Joshi, D. [City of Winnipeg, Winnipeg, MB (Canada); Klassen, K. [Manitoba Dept. of Energy Science and Technology, Winnipeg, MB (Canada); Phillips, B. [Unies Ltd., Winnipeg, MB (Canada); Wiebe, R. [Ben Wiebe Construction Ltd., Winnipeg, MB (Canada); Woelk, D. [Bockstael Construction Ltd., Winnipeg, MB (Canada); Ziemski, S. [CREIT Management LLP, Winnipeg, MB (Canada)

2006-09-15

This report presented a strategy and a set of recommendations for the adoption, development and implementation of an energy code for new commercial construction in Manitoba. The report was compiled by an advisory committee comprised of industry representatives and government agency representatives. Recommendations were divided into 4 categories: (1) advisory committee recommendations; (2) code adoption recommendations; (3) code development recommendations; and (4) code implementation recommendations. It was suggested that Manitoba should adopt an amended version of the Model National Energy Code for Buildings (1997) as a regulation under the Buildings and Mobile Homes Act. Participation in a national initiative to update the Model National Energy Code for Buildings was also advised. It was suggested that the energy code should be considered as the first step in a longer-term process towards a sustainable commercial building code. However, the code should be adopted within the context of a complete market transformation approach. Other recommendations included: the establishment of a multi-stakeholder energy code task group; the provision of information and technical resources to help build industry capacity; the establishment of a process for energy code compliance; and an ongoing review of the energy code to assess impacts and progress. Supplemental recommendations for future discussion included the need for integrated design by building design teams in Manitoba; the development of a program to provide technical assistance to building design teams; and collaboration between post-secondary institutions to develop and deliver courses on integrated building design to students and professionals. 17 refs.

Problems of Technology of Energy-Saving Buildings and Their Impact on Energy Efficiency in Buildings

Science.gov (United States)

Kwasnowski, Pawel; Fedorczak-Cisak, Malgorzata; Knap, Katarzyna

2017-10-01

Introduction of EPBD in legislation of the EU member states caused that buildings must meet very stringent requirements of thermal protection and energy efficiency. On the basis of EPBD provisions, EU Member States introduce standard of NZEB (Nearly Zero-Energy Buildings). Such activities cause a need for new, innovative materials and technologies, and new approaches to design, construction and retrofitting of buildings. Indispensable is the precise coordination of the design of structure and technical installations of building, which may be provided in an integrated design process in the system BIM. Good coordination and cooperation of all contractors during the construction phase is also necessary. The article presents the problems and the new methodology for the design, construction and use of energy efficient buildings in terms of energy saving technologies, including discussion of the significant impact of the automation of technical installations on the building energy efficiency.

Novel Methods to Explore Building Energy Sensitivity to Climate and Heat Waves Using PNNL's BEND Model

Science.gov (United States)

Burleyson, C. D.; Voisin, N.; Taylor, T.; Xie, Y.; Kraucunas, I.

2017-12-01

The DOE's Pacific Northwest National Laboratory (PNNL) has been developing the Building ENergy Demand (BEND) model to simulate energy usage in residential and commercial buildings responding to changes in weather, climate, population, and building technologies. At its core, BEND is a mechanism to aggregate EnergyPlus simulations of a large number of individual buildings with a diversity of characteristics over large spatial scales. We have completed a series of experiments to explore methods to calibrate the BEND model, measure its ability to capture interannual variability in energy demand due to weather using simulations of two distinct weather years, and understand the sensitivity to the number and location of weather stations used to force the model. The use of weather from "representative cities" reduces computational costs, but often fails to capture spatial heterogeneity that may be important for simulations aimed at understanding how building stocks respond to a changing climate (Fig. 1). We quantify the potential reduction in temperature and load biases from using an increasing number of weather stations across the western U.S., ranging from 8 to roughly 150. Using 8 stations results in an average absolute summertime temperature bias of 4.0°C. The mean absolute bias drops to 1.5°C using all available stations. Temperature biases of this magnitude translate to absolute summertime mean simulated load biases as high as 13.8%. Additionally, using only 8 representative weather stations can lead to a 20-40% bias of peak building loads under heat wave or cold snap conditions, a significant error for capacity expansion planners who may rely on these types of simulations. This analysis suggests that using 4 stations per climate zone may be sufficient for most purposes. Our novel approach, which requires no new EnergyPlus simulations, could be useful to other researchers designing or calibrating aggregate building model simulations - particularly those looking at

Low energy building with novel cooling unit using PCM

Energy Technology Data Exchange (ETDEWEB)

Jaber, Samar

2012-02-13

This thesis aims to reduce the energy consumption as well as greenhouse gases to the environment without negatively affecting the thermal comfort. In the present work, thermal, energetic and economic impacts of employing passive solar systems combined with energy conservation systems have been investigated. These energy systems have been integrated with a typical residential building located in three different climate zones in Europe and Middle East regions.Hour-by-hour energy computer simulations have been carried out using TRNSYS and INSEL programs to analyze the performance of integrated energy systems. Furthermore, IESU software module has been developed to simulate a novel cooling unit using Phase Change Material (PCM). This unit is named as Indirect Evaporative and Storage Unit (IESU). Thereafter, complete economic equations for the Life Cycle Cost (LCC) criterion have been formulated. Furthermore this criterion has been optimized for different variables as a function of thermal parameters and economic figures from local markets. An optimum design of both residential buildings and energy systems has great impact on energy consumption. In fact, results showed that the energy consumption is reduced by 85.62%, 86.33% and 74.05% in Berlin, Amman and Aqaba, respectively. Moreover, the LCC criterion is reduced by 41.85% in Berlin, 19.21% in Amman and 15.22% in Aqaba.The macro economic analysis shows that once this research is applied in one million typical residential buildings in the selected climate zones, the annual avoided CO{sub 2} emissions are estimated to be about 5.7 million Tons in Berlin. In Aqaba, around 2.96 million Tons CO{sub 2} emissions will be saved annually and in Amman about 2.98 million Tons will be reduced. The payback period from the achieved saving is 18 years, 11 years and 8.6 years in Amman, Aqaba and Berlin, respectively.

The role of grid-connected, building-integrated photovoltaic generation in commercial building energy and power loads in a warm and sunny climate

International Nuclear Information System (INIS)

Braun, P.; Ruether, R.

2010-01-01

For large commercial buildings, power load delivery limits are contracted with the local electricity distribution utility, and are usually fixed at one or more levels over the year, according to the seasonal building loads, and depending on the specific country regulations. Especially in warm and sunny climates, solar electricity generation using building-integrated photovoltaics (BIPV) can assist in reducing commercial building loads, offering peak-shaving (power) benefits on top of the on-site generation of electricity (energy). This on-site power delivery capability gives these consumers the possibility of renegotiating demand contracts with their distribution utility. Commercial buildings that operate during daytime quite often have an energy consumption profile that is well matched by solar radiation availability, and depending on the building's available surface areas, BIPV can generate considerable portions of the energy requirements. In this work we present the role of grid-connected BIPV in reducing the load demands of a large and urban commercial building located in a warm climate in Brazil. The building and adjacent car parking lots can accommodate a 1 MWp BIPV generator, which closely matches the building's typical maximum power demands. Based on real solar radiation data and simultaneous building electricity demands for the year 2007, simulation of the annual solar generation profile of this on-site generator showed that the 1 MWp BIPV system could account for around 30% of the total building's energy consumption. In addition to the energy benefit, maximum power demands were reduced due to a good match between midday air-conditioning cooling loads and solar radiation availability on both a daily and seasonal basis. Furthermore, we have simulated the effect of this considerably large urban-sited generator on the local distribution network load, and have shown that the 1 MWp BIPV installation can also offer considerable benefits to the local utility in

Assessing energy and thermal comfort of different low-energy cooling concepts for non-residential buildings

International Nuclear Information System (INIS)

Salvalai, Graziano; Pfafferott, Jens; Sesana, Marta Maria

2013-01-01

Highlights: • Impact of five cooling technologies are simulated in six European climate zones with Trnsys 17. • The ventilation strategies reduce the cooling energy need even in South Europe climate. • Constant ventilation controller can lead to a poor cooling performance. • Comparing radiant strategies with air conditioning scenario, the energy saving is predicted to within 5–35%. - Abstract: Energy consumption for cooling is growing dramatically. In the last years, electricity peak consumption grew significantly, switching from winter to summer in many EU countries. This is endangering the stability of electricity grids. This article outlines a comprehensive analysis of an office building performances in terms of energy consumption and thermal comfort (in accordance with static – ISO 7730:2005 – and adaptive thermal comfort criteria – EN 15251:2007 –) related to different cooling concepts in six different European climate zones. The work is based on a series of dynamic simulations carried out in the Trnsys 17 environment for a typical office building. The simulation study was accomplished for five cooling technologies: natural ventilation (NV), mechanical night ventilation (MV), fan-coils (FC), suspended ceiling panels (SCP), and concrete core conditioning (CCC) applied in Stockholm, Hamburg, Stuttgart, Milan, Rome, and Palermo. Under this premise, the authors propose a methodology for the evaluation of the cooling concepts taking into account both, thermal comfort and energy consumption

International Energy Agency Building Energy Simulation Test and Diagnostic Method for Heating, Ventilating, and Air-Conditioning Equipment Models (HVAC BESTEST); Volume 1: Cases E100-E200

Energy Technology Data Exchange (ETDEWEB)

Neymark, J.; Judkoff, R.

2002-01-01

This report describes the Building Energy Simulation Test for Heating, Ventilating, and Air-Conditioning Equipment Models (HVAC BESTEST) project conducted by the Tool Evaluation and Improvement International Energy Agency (IEA) Experts Group. The group was composed of experts from the Solar Heating and Cooling (SHC) Programme, Task 22, Subtask A. The current test cases, E100-E200, represent the beginning of work on mechanical equipment test cases; additional cases that would expand the current test suite have been proposed for future development.

Occupant responses and energy use in buildings with moderately drifting temperatures

DEFF Research Database (Denmark)

Toftum, Jørn; Olesen, Bjarne W.; Kolarik, Jakub

of installed HVAC system capacity was evaluated by dynamic simulation of building energy consumption and indoor environment, taking into account potential effects on occupants of such non-steady thermal environments. Several building HVAC configurations and locations with different outdoor climate conditions...... were simulated. Two different approaches were used in the human subject experiments; a) exposure of human subjects to temperature ramps with fixed clothing insulation and b) with subjects being allowed to adjust their clothing insulation as desired. In the former experiments, subjects’ thermal...

Smart buildings: Energy efficient conditioning of building occupants

NARCIS (Netherlands)

Zeiler, W.; Houten, van M.A.; Boxem, G.; Vehler, R.; Verhoeven, M.; Fremouw, M.

2009-01-01

To further optimize energy performance of buildings, intelligent building control offers new possibilities. Intelligent Software Agents (ISA) can be implemented at different levels of building automation. Individual agents for individual climate control for each user of the building in combination

Residential building envelope heat gain and cooling energy requirements

International Nuclear Information System (INIS)

Lam, Joseph C.; Tsang, C.L.; Li, Danny H.W.; Cheung, S.O.

2005-01-01

We present the energy use situation in Hong Kong from 1979 to 2001. The primary energy requirement (PER) nearly tripled during the 23-year period, rising from 195,405 TJ to 572,684 TJ. Most of the PER was used for electricity generation, and the electricity use in residential buildings rose from 7556 TJ (2099 GWh) to 32,799 TJ (9111 GWh), an increase of 334%. Air-conditioning accounted for about 40% of the total residential sector electricity consumption. A total of 144 buildings completed in the month of June during 1992-2001 were surveyed. Energy performance of the building envelopes was investigated in terms of the overall thermal transfer value (OTTV). To develop the appropriated parameters used in OTTV calculation, long-term measured weather data such as ambient temperature (1960-2001), horizontal global solar radiation (1992-2001) and global solar radiation on vertical surfaces (1996-2001) were examined. The OTTV found varied from 27 to 44 W/m 2 with a mean value of 37.7 W/m 2 . Building energy simulation technique using DOE-2.1E was employed to determine the cooling requirements and hence electricity use for building envelope designs with different OTTVs. It was found that cooling loads and electricity use could be expressed in terms of a simple two-parameter linear regression equation involving OTTV

Weather Correlations to Calculate Infiltration Rates for U. S. Commercial Building Energy Models.

Science.gov (United States)

Ng, Lisa C; Quiles, Nelson Ojeda; Dols, W Stuart; Emmerich, Steven J

2018-01-01

As building envelope performance improves, a greater percentage of building energy loss will occur through envelope leakage. Although the energy impacts of infiltration on building energy use can be significant, current energy simulation software have limited ability to accurately account for envelope infiltration and the impacts of improved airtightness. This paper extends previous work by the National Institute of Standards and Technology that developed a set of EnergyPlus inputs for modeling infiltration in several commercial reference buildings using Chicago weather. The current work includes cities in seven additional climate zones and uses the updated versions of the prototype commercial building types developed by the Pacific Northwest National Laboratory for the U. S. Department of Energy. Comparisons were made between the predicted infiltration rates using three representations of the commercial building types: PNNL EnergyPlus models, CONTAM models, and EnergyPlus models using the infiltration inputs developed in this paper. The newly developed infiltration inputs in EnergyPlus yielded average annual increases of 3 % and 8 % in the HVAC electrical and gas use, respectively, over the original infiltration inputs in the PNNL EnergyPlus models. When analyzing the benefits of building envelope airtightening, greater HVAC energy savings were predicted using the newly developed infiltration inputs in EnergyPlus compared with using the original infiltration inputs. These results indicate that the effects of infiltration on HVAC energy use can be significant and that infiltration can and should be better accounted for in whole-building energy models.

A Study on Development of a Cost Optimal and Energy Saving Building Model: Focused on Industrial Building

Directory of Open Access Journals (Sweden)

Hye Yeon Kim

2016-03-01

Full Text Available This study suggests an optimization method for the life cycle cost (LCC in an economic feasibility analysis when applying energy saving techniques in the early design stage of a building. Literature and previous studies were reviewed to select appropriate optimization and LCC analysis techniques. The energy simulation (Energy Plus and computational program (MATLAB were linked to provide an automated optimization process. From the results, it is suggested that this process could outline the cost optimization model with which it is possible to minimize the LCC. To aid in understanding the model, a case study on an industrial building was performed to outline the operations of the cost optimization model including energy savings. An energy optimization model was also presented to illustrate the need for the cost optimization model.

The comparison of the energy performance of hotel buildings using PROMETHEE decision-making method

Directory of Open Access Journals (Sweden)

Vujosevic Milica L.

2016-01-01

Full Text Available Annual energy performance of the atrium type hotel buildings in Belgrade climate conditions are analysed in this paper. The objective is to examine the impact of the atrium on the hotel building’s energy needs for space heating and cooling, thus establishing the best design among four proposed alternatives of the hotels with atrium. The energy performance results are obtained using EnergyPlus simulation engine, taking into account Belgrade climate data and thermal comfort parameters. The selected results are compared and the hotels are ranked according to certain criteria. Decision-making process that resulted in the ranking of the proposed alternatives is conducted using PROMETHEE method and Borda model. The methodological approach in this research includes the creation of a hypothetical model of an atrium type hotel building, numerical simulation of energy performances of four design alternatives of the hotel building with an atrium, comparative analysis of the obtained results and ranking of the proposed alternatives from the building’s energy performance perspective. The main task of the analysis is to examine the influence of the atrium, with both its shape and position, on the energy performance of the hotel building. Based on the results of the research it can be to determine the most energy efficient model of the hotel building with atrium for Belgrade climate condition areas. [Projekat Ministarstva nauke Republike Srbije: Spatial, Environmental, Energy and Social aspects of the Developing Settlements and Climate Change - Mutual Impacts

Combination of low energy and mechanical cooling technologies for buildings in Central Europe

NARCIS (Netherlands)

Lain, M.; Hensen, J.L.M.

2004-01-01

This paper discusses options for incorporating low energy cooling technologies combined with standard mechanical cooling in buildings in central Europe. Case studies, design recommendations and role of computer simulation of building and system in the design process are presented. Applicability of

Integration of Low Energy Technologies for Optimal Building and Space Conditioning Design

Energy Technology Data Exchange (ETDEWEB)

D.E. Fisher

2006-01-07

EnergyPlus is the DOE's newest building energy simulation engine. It was developed specifically to support the design of low energy building systems. This project focused on developing new low energy building simulation models for EnergyPlus, verifying and validating new and existing EnergyPlus models and transferring the new technology to the private sector. The project focused primarily on geothermal and radiant technologies, which are related by the fact that both are based on hydronic system design. As a result of this project eight peer reviewed journal and conference papers were added to the archival literature and five technical reports were published as M.S. theses and are available in the archival literature. In addition, several reports, including a trombe wall validation report were written for web publication. Thirteen new or significantly enhanced modules were added to the EnergyPlus source code and forty-two new or significantly enhanced sections were added to the EnergyPlus documentation as a result of this work. A low energy design guide was also developed as a pedagogical tool and is available for web publication. Finally several tools including a hybrid ground source heat pump optimization program and a geothermal heat pump parameter estimation tool were developed for research and design and are available for web publication.

Dynamic Simulation of the Green Roofs Impact on Building Energy Performance, Case Study of Antananarivo, Madagascar

Directory of Open Access Journals (Sweden)

Hery Tiana Rakotondramiarana

2015-05-01

Full Text Available Green roofs improve building energy performance and constitute an alternative to sustainable buildings. A green roof model is dynamically coupled with a building thermal model to assess its energy performance that takes into account the indoor air temperature dynamic changes. Under the climate conditions in Antananarivo, we compared green and conventional roofs. The present study shows that green roofs protect the roof structure under extreme temperature and large temperature fluctuations. For the case of Antananarivo, the amplitude of the temperature fluctuations at the top face of the support is reduced by 28 °C when using green roof. The impact of the green roof on indoor air temperature and energy demand is investigated. The vegetation decreases the maximum indoor air temperature and improves the building thermal comfort during summer days. It has no effect on the minimum indoor air temperature, but additional soil thickness can increase it. In addition, a global sensitivity analysis, which is carried out on the proposed model without considering any specific weather data, allows us to identify the most influential parameters on the energy demand. It has been found that green roofs have almost insignificant thermal impact in insulated buildings; however, their potential prevails over the building envelope and weather characteristics in the case of non-insulated building.

Energy efficiency of residential buildings. Energy consumption and investment costs of different building energy standards; Energieeffizienz von Wohngebaeuden. Energieverbraeuche und Investitionskosten energetischer Gebaeudestandards

Energy Technology Data Exchange (ETDEWEB)

Beecken, Christoph; Schulze, Stephan [Bow Ingenieure GmbH, Braunschweig (Germany)

2011-12-15

In view of the impending energy transition in Germany, turning away from fossil fuels and atomic power and leading to renewable energy sources, the construction of very energy efficient new buildings gains more and more in importance. Because the saving of energy with efficient buildings offers the highest potential to achieve the energy transition without loss of comfort and also complying with the climate protection target of limitation of the carbon dioxide emission. For new buildings in the initial project planning phase, the client needs qualified consulting concerning a reasonable energy standard for his building. The consulting should comprise the multitude of energy efficiency standards and the related financial incentives and not only cover the minimum standard of the German Building Energy Conservation Regulation EnEV (Energieeinsparverordnung). But the architect can hardly quantify the potentials to reduce energy consumption of buildings considering the multitude of existing standards with multifarious effects on energy consumption, technical requirements and building costs. With the help of an example multi-storey residential building in Hannover, current energy standards for residential buildings are compared. Besides the building construction also the building services like heating, hot water generation and ventilation are considered and the most important results concerning energy consumption and investment costs are compared.

Design of energy efficient building with radiant slab cooling

Science.gov (United States)

Tian, Zhen

2007-12-01

Air-conditioning comprises a substantial fraction of commercial building energy use because of compressor-driven refrigeration and fan-driven air circulation. Core regions of large buildings require year-round cooling due to heat gains from people, lights and equipment. Negative environmental impacts include CO2 emissions from electric generation and leakage of ozone-depleting refrigerants. Some argue that radiant cooling simultaneously improves building efficiency and occupant thermal comfort, and that current thermal comfort models fail to reflect occupant experience with radiant thermal control systems. There is little field evidence to test these claims. The University of Calgary's Information and Communications Technology (ICT) Building, is a pioneering radiant slab cooling installation in North America. Thermal comfort and energy performance were evaluated. Measurements included: (1) heating and cooling energy use, (2) electrical energy use for lighting and equipment, and (3) indoor temperatures. Accuracy of a whole building energy simulation model was evaluated with these data. Simulation was then used to compare the radiant slab design with a conventional (variable air volume) system. The radiant system energy performance was found to be poorer mainly due to: (1) simultaneous cooling by the slab and heating by other systems, (2) omission of low-exergy (e.g., groundwater) cooling possible with the high cooling water temperatures possible with radiant slabs and (3) excessive solar gain and conductive heat loss due to the wall and fenestration design. Occupant thermal comfort was evaluated through questionnaires and concurrent measurement of workstation comfort parameters. Analysis of 116 sets of data from 82 occupants showed that occupant assessment was consistent with estimates based on current thermal comfort models. The main thermal comfort improvements were reductions in (1) local discomfort from draft and (2) vertical air temperature stratification. The

Thermal and Energy Performance of Conditioned Building Due To Insulated Sloped Roof

Science.gov (United States)

Irwan, Suhandi Syiful; Ahmed, Azni Zain; Zakaria, Nor Zaini; Ibrahim, Norhati

2010-07-01

For low-rise buildings in equatorial region, the roof is exposed to solar radiation longer than other parts of the envelope. Roofs are to be designed to reject heat and moderate the thermal impact. These are determined by the design and construction of the roofing system. The pitch of roof and the properties of construction affect the heat gain into the attic and subsequently the indoor temperature of the living spaces underneath. This finally influences the thermal comfort conditions of naturally ventilated buildings and cooling load of conditioned buildings. This study investigated the effect of insulated sloping roof on thermal energy performance of the building. A whole-building thermal energy computer simulation tool, Integrated Environmental Solution (IES), was used for the modelling and analyses. A building model with dimension of 4.0 m × 4.0 m × 3.0 m was designed with insulated roof and conventional construction for other parts of the envelope. A 75 mm conductive insulation material with thermal conductivity (k-value) of 0.034 Wm-1K-1 was installed underneath the roof tiles. The building was modelled with roof pitch angles of 0° , 15°, 30°, 45°, 60° and simulated for the month of August in Malaysian climate conditions. The profile for attic temperature, indoor temperature and cooling load were downloaded and evaluated. The optimum roof pitch angle for best thermal performance and energy saving was identified. The results show the pitch angle of 0° is able to mitigate the thermal impact to provide the best thermal condition with optimum energy savings. The maximum temperature difference between insulated and non-insulted roof for attic (AtticA-B) and indoor condition (IndoorA-B) is +7.8 °C and 0.4 °C respectively with an average energy monthly savings of 3.9 %.

ASEAN-USAID Buildings Energy Conservation Project. Final report, Volume 3: Audits

Energy Technology Data Exchange (ETDEWEB)

Loewen, J.M.; Levine, M.D.; Busch, J.F. [eds.

1992-06-01

The auditing subproject of the ASEAN-USAID Buildings Energy Conservation Project has generated a great deal of auditing activity throughout the ASEAN region. Basic building characterisfic and energy consumption data were gathered for over 200 buildings and are presented in this volume. A large number of buildings were given more detailed audits and were modeled with either the ASEAM-2 computer program or the more complex DOE-2 program. These models were used to calculate the savings to be generated by conservabon measures. Specially audits were also conducted, including lighting and thermal comfort surveys. Many researchers in the ASEAN region were trained to perform energy audits in a series of training courses and seminars. The electricity intensifies of various types of ASEAN buildings have been calculated. A comparison to the electricity intensity of the US building stock tentatively concludes that ASEAN office buildings are comparable, first class hotels and retail stores are more ewctricity intensive than their US counterparts, and hospitals are less intensive. Philippine and Singapore lighting surveys indicate that illuminance levels in offices tend to be below the minimum accepted standard. Computer simulations of the energy use in various building types generally agree that for most ASEAN buildings, electricity consumption for air-conditioning (including fan power) consumes approximately 60% of total building electricity. A review of the many studies made during the Project to calculate the savings from energy conservation opportunities (ECOS) shows a median potential savings of approximately 10%, with some buildings saving as much as 50%. Singapore buildings, apparently as a result of previously implemented efficient energy-use practices, shows a lower potential for savings than the other ASEAN nations. Air-conditioning ECOs hold the greatest potential for savings.

Model-based and model-free “plug-and-play” building energy efficient control

International Nuclear Information System (INIS)

Baldi, Simone; Michailidis, Iakovos; Ravanis, Christos; Kosmatopoulos, Elias B.

2015-01-01

Highlights: • “Plug-and-play” Building Optimization and Control (BOC) driven by building data. • Ability to handle the large-scale and complex nature of the BOC problem. • Adaptation to learn the optimal BOC policy when no building model is available. • Comparisons with rule-based and advanced BOC strategies. • Simulation and real-life experiments in a ten-office building. - Abstract: Considerable research efforts in Building Optimization and Control (BOC) have been directed toward the development of “plug-and-play” BOC systems that can achieve energy efficiency without compromising thermal comfort and without the need of qualified personnel engaged in a tedious and time-consuming manual fine-tuning phase. In this paper, we report on how a recently introduced Parametrized Cognitive Adaptive Optimization – abbreviated as PCAO – can be used toward the design of both model-based and model-free “plug-and-play” BOC systems, with minimum human effort required to accomplish the design. In the model-based case, PCAO assesses the performance of its control strategy via a simulation model of the building dynamics; in the model-free case, PCAO optimizes its control strategy without relying on any model of the building dynamics. Extensive simulation and real-life experiments performed on a 10-office building demonstrate the effectiveness of the PCAO–BOC system in providing significant energy efficiency and improved thermal comfort. The mechanisms embedded within PCAO render it capable of automatically and quickly learning an efficient BOC strategy either in the presence of complex nonlinear simulation models of the building dynamics (model-based) or when no model for the building dynamics is available (model-free). Comparative studies with alternative state-of-the-art BOC systems show the effectiveness of the PCAO–BOC solution

Low-energy district heating in energy-efficient building areas

International Nuclear Information System (INIS)

Dalla Rosa, A.; Christensen, J.E.

2011-01-01

This paper presents an innovative low-energy district heating (DH) concept based on low-temperature operation. The decreased heating demand from low-energy buildings affects the cost-effectiveness of traditionally-designed DH systems, so we carried out a case study of the annual energy performance of a low-energy network for low-energy houses in Denmark. We took into account the effect of human behaviour on energy demand, the effect of the number of buildings connected to the network, a socio-economic comparison with ground source heat pumps, and opportunities for the optimization of the network design, and operational temperature and pressure. In the north-European climate, we found that human behaviour can lead to 50% higher heating demand and 60% higher heating power than those anticipated in the reference values in the standard calculations for energy demand patterns in energy-efficient buildings. This considerable impact of human behaviour should clearly be included in energy simulations. We also showed that low-energy DH systems are robust systems that ensure security of supply for each customer in a cost-effective and environmentally friendly way in areas with linear heat density down to 0.20 MWh/(m year), and that the levelized cost of energy in low-energy DH supply is competitive with a scenario based on ground source heat pumps. The investment costs represent up to three quarters of the overall expenditure, over a time horizon of 30 years; so, the implementation of an energy system that fully relies on renewable energy needs substantial capital investment, but in the long term this is sustainable from the environmental and socio-economic points of view. Having demonstrated the value of the low-energy DH concept, we evaluated various possible designs with the aim of finding the optimal solution with regard to economic and energy efficiency issues. Here we showed the advantage of low supply and return temperatures, their effect on energy efficiency and that

Energy requirements for new buildings in Finland

Energy Technology Data Exchange (ETDEWEB)

Airaksinen, M., Email: miimu.airaksinen@vtt.fi

2012-06-15

Buildings account for circa 40% of the total energy use in Europe [1] and for about 36% of the EU's total CO{sub 2} emissions [2], including the existing energy conservation in buildings [3]. Key features of the Finnish energy policy are improved energy efficiency and increased use of renewable energy sources. To achieve a sustainable shift in the energy system, a target set by the authorities, both energy savings and increased use of low-pollution energy sources are therefore priority areas. Building low-energy buildings is in accordance with the declared national aim of reducing energy use and thus reducing CO{sub 2} emissions. The main motivation in renewing building codes for new buildings was to build more energy efficiently, encourage the use the most efficient energy sources and to enhance the use of renewable energy sources. In addition the aim was to give more freedom to fi nd the real optimal solutions for energy efficiency by optimising all aspects including the building architecture and different systems with demand controls. However, in order to ensure the good quality of buildings certain minimum requirements for structure U-values are given. (orig.)

Intervention strategies for energy efficient municipal buildings: Influencing energy decisions throughout buildings` lifetimes

Energy Technology Data Exchange (ETDEWEB)

NONE

1993-12-31

The current energy-related decisionmaking processes that take place during the lifetimes of municipal buildings in San Francisco do not reflect our ideal picture of energy efficiency as a part of staff awareness and standard practice. Two key problems that undermine the success of energy efficiency programs are lost opportunities and incomplete actions. These problems can be caused by technology-related issues, but often the causes are institutional barriers (organizational or procedural {open_quotes}people problems{close_quotes}). Energy efficient decisions are not being made because of a lack of awareness or policy mandate, or because financial resources are not available to decisionmakers. The Bureau of Energy Conservation (BEC) is working to solve such problems in the City & County of San Francisco through the Intervention Strategies project. In the first phase of the project, using the framework of the building lifetime, we learned how energy efficiency in San Francisco municipal buildings can be influenced through delivering services to support decisionmakers; at key points in the process of funding, designing, constructing and maintaining them. The second phase of the project involved choosing and implementing five pilot projects. Through staff interviews, we learned how decisions that impact energy use are made at various levels. We compiled information about city staff and their needs, and resources available to meet those needs. We then designed actions to deliver appropriate services to staff at these key access points. BEC implemented five pilot projects corresponding to various stages in the building`s lifetime. These were: Bond Guidelines, Energy Efficient Design Practices, Commissioning, Motor Efficiency, and Facilities Condition Monitoring Program.

Estimation of the Relationship Between Remotely Sensed Anthropogenic Heat Discharge and Building Energy Use

Science.gov (United States)

Zhou, Yuyu; Weng, Qihao; Gurney, Kevin R.; Shuai, Yanmin; Hu, Xuefei

2012-01-01

This paper examined the relationship between remotely sensed anthropogenic heat discharge and energy use from residential and commercial buildings across multiple scales in the city of Indianapolis, Indiana, USA. The anthropogenic heat discharge was estimated with a remote sensing-based surface energy balance model, which was parameterized using land cover, land surface temperature, albedo, and meteorological data. The building energy use was estimated using a GIS-based building energy simulation model in conjunction with Department of Energy/Energy Information Administration survey data, the Assessor's parcel data, GIS floor areas data, and remote sensing-derived building height data. The spatial patterns of anthropogenic heat discharge and energy use from residential and commercial buildings were analyzed and compared. Quantitative relationships were evaluated across multiple scales from pixel aggregation to census block. The results indicate that anthropogenic heat discharge is consistent with building energy use in terms of the spatial pattern, and that building energy use accounts for a significant fraction of anthropogenic heat discharge. The research also implies that the relationship between anthropogenic heat discharge and building energy use is scale-dependent. The simultaneous estimation of anthropogenic heat discharge and building energy use via two independent methods improves the understanding of the surface energy balance in an urban landscape. The anthropogenic heat discharge derived from remote sensing and meteorological data may be able to serve as a spatial distribution proxy for spatially-resolved building energy use, and even for fossil-fuel CO2 emissions if additional factors are considered.

Energy Performance Certificate of building and confidence interval in assessment: An Italian case study

International Nuclear Information System (INIS)

Tronchin, Lamberto; Fabbri, Kristian

2012-01-01

The Directive 2002/91/CE introduced the Energy Performance Certificate (EPC), an energy policy tool. The aim of the EPC is to inform building buyers about the energy performance and energy costs of buildings. The EPCs represent a specific energy policy tool to orient the building sector and real-estate markets toward higher energy efficiency buildings. The effectiveness of the EPC depends on two factors: •The accuracy of energy performance evaluation made by independent experts. •The capability of the energy classification and of the scale of energy performance to control the energy index fluctuations. In this paper, the results of a case study located in Italy are shown. In this example, 162 independent technicians on energy performance of building evaluation have studied the same building. The results reveal which part of confidence intervals is dependent on software misunderstanding and that the energy classification ranges are able to tolerate the fluctuation of energy indices. The example was chosen in accordance with the legislation of the Emilia-Romagna Region on Energy Efficiency of Buildings. Following these results, some thermo-economic evaluation related to building and energy labelling are illustrated, as the EPC, which is an energy policy tool for the real-estate market and building sector to find a way to build or retrofit an energy efficiency building. - Highlights: ► Evaluation of the accuracy of energy performance of buildings in relation with the knowledge of independent experts. ► Round robin test based on 162 case studies on the confidence intervals expressed by independent experts. ► Statistical considerations between the confidence intervals expressed by independent experts and energy simulation software. ► Relation between “proper class” in energy classification of buildings and confidence intervals of independent experts.

NASA Net Zero Energy Buildings Roadmap

Energy Technology Data Exchange (ETDEWEB)

Pless, S.; Scheib, J.; Torcellini, P.; Hendron, B.; Slovensky, M.

2014-10-01

In preparation for the time-phased net zero energy requirement for new federal buildings starting in 2020, set forth in Executive Order 13514, NASA requested that the National Renewable Energy Laboratory (NREL) to develop a roadmap for NASA's compliance. NASA detailed a Statement of Work that requested information on strategic, organizational, and tactical aspects of net zero energy buildings. In response, this document presents a high-level approach to net zero energy planning, design, construction, and operations, based on NREL's first-hand experience procuring net zero energy construction, and based on NREL and other industry research on net zero energy feasibility. The strategic approach to net zero energy starts with an interpretation of the executive order language relating to net zero energy. Specifically, this roadmap defines a net zero energy acquisition process as one that sets an aggressive energy use intensity goal for the building in project planning, meets the reduced demand goal through energy efficiency strategies and technologies, then adds renewable energy in a prioritized manner, using building-associated, emission- free sources first, to offset the annual energy use required at the building; the net zero energy process extends through the life of the building, requiring a balance of energy use and production in each calendar year.

Building occupancy diversity and HVAC (heating, ventilation, and air conditioning) system energy efficiency

International Nuclear Information System (INIS)

Yang, Zheng; Ghahramani, Ali; Becerik-Gerber, Burcin

2016-01-01

Approximately forty percent of total building energy consumption is attributed to HVAC (heating, ventilation, and air conditioning) systems that aim to maintain healthy and comfortable indoor environments. An HVAC system is a network with several subsystems, and there exist heat transfer and balance among the zones of a building, as well as heat gains and losses through a building's envelope. Diverse occupancy (diversity in terms of when and how occupants occupy a building) in spaces could result in increase of loads that are not actual demands for an HVAC system, leading into inefficiencies. This paper introduces a framework to quantitatively evaluate the energy implications of occupancy diversity at the building level, where building information modeling is integrated to provide building geometries, HVAC system layouts, and spatial information as inputs for computing potential energy implications if occupancy diversity were to be eliminated. An agglomerate hierarchical clustering-based iterative evaluation algorithm is designed for iteratively eliminating occupancy diversity. Whole building energy simulations for a real-world building, as well as virtual reference buildings demonstrate that the proposed framework could effectively quantify the HVAC system energy efficiency affected by occupancy diversity and the framework is generalizable to different building geometries, layouts, and occupancy diversities. - Highlights: • Analyze relationships between occupancy diversity and HVAC energy efficiency. • Integrate BIM for quantifying energy implications of occupancy diversity. • Demonstrate the effectiveness and generalizability of iterative evaluation algorithm. • Improve agglomerative hierarchical clustering process using heap data structure.

Energy and Environmental Research in the Building Area; Forschen und Bauen im Kontext von Energie und Umwelt

Energy Technology Data Exchange (ETDEWEB)

Binz, A. [Fachhochschule Nordwestschweiz (HABG-IEB), Muttenz (Switzerland); Chianese, D. [Scuola Universitaria Professionale della Svizzera Italiana, Dipartimento Ambiente Costruzioni e Design, Instituto di Sostenibilita Applicata all' Ambiente Costruito (SUPSI-DACD-ISAAC), Canobbio (Switzerland); Filleux, Ch. [Basler und Hofmann, Zuerich (Switzerland); Gaegauf, Ch. [Oekozentrum Langenbruck, Langenbruck (Switzerland); Gugerli, H. [Amt fuer Hochbauten der Stadt Zuerich, Zuerich (Switzerland); Menti, U.-P. [Hochschule Luzern, Technik und Architektur, Horw (Switzerland); Rommel, M. [Hochschule fuer Technik, Institut fuer Solartechnik (SPF), Rapperswil (Switzerland); Schwehr, P. [brenet, building and renewable energies network of technology, HTA Luzern, Horw (Switzerland); Zimmermann, M. [Swiss Federal Laboratories for Materials Testing and Research (EMPA), Duebendorf (Switzerland)

2010-07-01

These proceedings of the 16{sup th} Swiss Status Seminar held in September 2010 at the Swiss Federal Institute of Technology ETH in Zurich, Switzerland, present a comprehensive overview of the two-day event on Swiss energy and environmental topics in the building area. A total of 55 lectures in ten sessions covered architectural and building topics. The main lectures at the beginning of the seminar covered models for sustainable city development, building for the 2000-watt society and design principles. Also the 'Tropical House' project, the 'Self' autonomous house, the new Monte Rosa mountaineers hut and the Swiss Village project in Masdar were presented. The presentations were divided into nine thematic areas: The house as a 'power station', building renewal, energy management, heat pumps, processes, innovative building and renovation, city districts, building technologies, ventilation and the building as a system. Twenty poster contributions completed the seminar. Themes addressed in the 'house as a power station' set looked at the local generation of power, buildings that generate or even export energy and low-energy consumption buildings. Building renewal topics discussed included grey energy and legal topics, energy management contributions dealt with control, hot water preparation and energy efficiency. The heat pump section dealt with theory and practice of heating and cooling, multi-functional and low-exergy systems and related calculation aids. The processes section included contributions on infra-red analysis, solar-assisted systems, modelling, eco-balances and the City of Zurich's resource strategy for mineral building materials. Innovative building and renovation topics included renovation with prefabricated elements, integrated photovoltaic modules, retrofits as well as financing topics. The topics covered in the district development set included contributions on sustainable (re-)development, the 2000-watt

Impact of window selection on the energy performance of residential buildings in South Korea

International Nuclear Information System (INIS)

Ihm, Pyeongchan; Park, Lyool; Krarti, Moncef; Seo, Donghyun

2012-01-01

With rapidly increasing energy consumption attributed to residential buildings in South Korea, there is a need to update requirements of the building energy code in order to improve the energy performance of buildings. This paper provides some guidelines to improve the building energy code to better select glazing types that minimize total energy use of residential buildings in Korea. In particular, detailed energy simulation analyses coupled with economical and environmental assessments are carried out to assess the thermal, economical, and environmental impacts of glazing thermal characteristics as well as window sizes associated with housing units in various representative climates within South Korea. The results of the analyses have clearly indicated that selecting glazing with low solar heat gain coefficient is highly beneficial especially for large windows and for mild climates. In particular, it is found that using any double-pane low-e glazing would provide better performance for windows in residential buildings than the clear double-pane glazing, currently required by the Korean building energy code. - Highlights: ► Results show that windows can be energy neutral for residential buildings. ► In Korea, double-pane low-e glazing would provide better energy performance. ► Double low-e clear filled with argon gas glazing is the most cost-effective.

Recent Developments of the Modelica"Buildings" Library for Building Energy and Control Systems

Energy Technology Data Exchange (ETDEWEB)

Wetter, Michael; Zuo, Wangda; Nouidui, Thierry Stephane

2011-04-01

At the Modelica 2009 conference, we introduced the Buildings library, a freely available Modelica library for building energy and control systems. This paper reports the updates of the library and presents example applications for a range of heating, ventilation and air conditioning (HVAC) systems. Over the past two years, the library has been further developed. The number of HVAC components models has been doubled and various components have been revised to increase numerical robustness.The paper starts with an overview of the library architecture and a description of the main packages. To demonstrate the features of the Buildings library, applications that include multizone airflow simulation as well as supervisory and local loop control of a variable air volume (VAV) system are briefly described. The paper closes with a discussion of the current development.

Optimizing Energy Consumption in Building Designs Using Building Information Model (BIM

Directory of Open Access Journals (Sweden)

Egwunatum Samuel

2016-09-01

Full Text Available Given the ability of a Building Information Model (BIM to serve as a multi-disciplinary data repository, this paper seeks to explore and exploit the sustainability value of Building Information Modelling/models in delivering buildings that require less energy for their operation, emit less CO2 and at the same time provide a comfortable living environment for their occupants. This objective was achieved by a critical and extensive review of the literature covering: (1 building energy consumption, (2 building energy performance and analysis, and (3 building information modeling and energy assessment. The literature cited in this paper showed that linking an energy analysis tool with a BIM model helped project design teams to predict and create optimized energy consumption. To validate this finding, an in-depth analysis was carried out on a completed BIM integrated construction project using the Arboleda Project in the Dominican Republic. The findings showed that the BIM-based energy analysis helped the design team achieve the world’s first 103% positive energy building. From the research findings, the paper concludes that linking an energy analysis tool with a BIM model helps to expedite the energy analysis process, provide more detailed and accurate results as well as deliver energy-efficient buildings. The study further recommends that the adoption of a level 2 BIM and the integration of BIM in energy optimization analyse should be made compulsory for all projects irrespective of the method of procurement (government-funded or otherwise or its size.

Modeling Boston: A workflow for the efficient generation and maintenance of urban building energy models from existing geospatial datasets

International Nuclear Information System (INIS)

Cerezo Davila, Carlos; Reinhart, Christoph F.; Bemis, Jamie L.

2016-01-01

City governments and energy utilities are increasingly focusing on the development of energy efficiency strategies for buildings as a key component in emission reduction plans and energy supply strategies. To support these diverse needs, a new generation of Urban Building Energy Models (UBEM) is currently being developed and validated to estimate citywide hourly energy demands at the building level. However, in order for cities to rely on UBEMs, effective model generation and maintenance workflows are needed based on existing urban data structures. Within this context, the authors collaborated with the Boston Redevelopment Authority to develop a citywide UBEM based on official GIS datasets and a custom building archetype library. Energy models for 83,541 buildings were generated and assigned one of 52 use/age archetypes, within the CAD modelling environment Rhinoceros3D. The buildings were then simulated using the US DOE EnergyPlus simulation program, and results for buildings of the same archetype were crosschecked against data from the US national energy consumption surveys. A district-level intervention combining photovoltaics with demand side management is presented to demonstrate the ability of UBEM to provide actionable information. Lack of widely available archetype templates and metered energy data, were identified as key barriers within existing workflows that may impede cities from effectively applying UBEM to guide energy policy. - Highlights: • Data requirements for Urban Building Energy Models are reviewed. • A workflow for UBEM generation from available GIS datasets is developed. • A citywide demand simulation model for Boston is generated and tested. • Limitations for UBEM in current urban data systems are identified and discussed. • Model application for energy management policy is shown in an urban PV scenario.

Application of users’ light-switch stochastic models to dynamic energy simulation

DEFF Research Database (Denmark)

Camisassi, V.; Fabi, V.; Andersen, Rune Korsholm

2015-01-01

deterministic inputs, due to the uncertain nature of human behaviour. In this paper, new stochastic models of users’ interaction with artificial lighting systems are developed and implemented in the energy simulation software IDA ICE. They were developed from field measurements in an office building in Prague......The design of an innovative building should include building overall energy flows estimation. They are principally related to main six influencing factors (IEA-ECB Annex 53): climate, building envelope and equipment, operation and maintenance, occupant behaviour and indoor environment conditions...

Energy conservation in existing office buildings. Appendices to report, Phase I, Volume 2

Energy Technology Data Exchange (ETDEWEB)

1977-06-01

A blank form of Questionnaire No. 1 is first presented, followed by data compiled from that questionnaire. Then data are presented on the analyses of the 436 buildings, statistical validation for selection of the 44 building sample, and some examples of the matching buildings for the 44 building sample. Questionnaire No. 2 is then given, followed by additional data collected from the study concerning energy consumption and building characteristics. To complete the appendices, a simulation of a typical building and a hypothetical building is included. (MCW)

Understanding Net Zero Energy Buildings

DEFF Research Database (Denmark)

Salom, Jaume; Widén, Joakim; Candanedo, José

2011-01-01

Although several alternative definitions exist, a Net-Zero Energy Building (Net ZEB) can be succinctly described as a grid-connected building that generates as much energy as it uses over a year. The “net-zero” balance is attained by applying energy conservation and efficiency measures...... and by incorporating renewable energy systems. While based on annual balances, a complete description of a Net ZEB requires examining the system at smaller time-scales. This assessment should address: (a) the relationship between power generation and building loads and (b) the resulting interaction with the power grid...

Using passive cooling strategies to improve thermal performance and reduce energy consumption of residential buildings in U.A.E. buildings