Project group members and presentation time Thursday Chris Holcomb Cristian Wolleter Michelle Noriega Mei Baumann, Zahid Alibhai, Ellie Azolaty Randy Maddox and Garrett Jones Mariel Kerbacher Friday Jeremy Theodore Steve Bourne Jordan Clark and Adam Keeling Meg Gunther and Nick David Joshua Rhodes and Marwa Farhat Yogita Manan and Kostas Mouratideis Sarah Johnson, Jocelyn Citty, Benjamin Ash Lauren Davis and Marcus Allen Jae Koh and Kenneth Graeves Presentation length: 8 minutes presentation + 2 minutes for questions

Lecture Objectives: Discuss accuracy of energy modeling Talk about available modeling tools Review the course outcome

What are the reasons for energy simulations? System Development Building design improvement Economic benefits Budget planning

How to evaluate the whole building simulation tools Two options: 1)Comparison with the experimental data - monitoring - very expensive - feasible only for smaller buildings 2) Comparison with other energy simulation programs - for the same input data - system of numerical experiments - BESTEST

Comparison with measured data Cranfield test rooms (from Lomas et al 1994a)

BESTEST Building Energy Simulation TEST System of tests (~ 40 cases) - Each test emphasizes certain phenomena like external (internal) convection, radiation, ground contact -Simple geometry -Mountain climate COMPARE THE RESULTS

Example of best test comparison

What are the reasons for energy simulations? System Development Building design improvement Economic benefits Budget planning

Life Cycle Cost Analysis Engineering economics

Example Using eQUEST analyze the benefits (energy saving and pay back period) of installing - low-e double glazed window - variable frequency drive in a school building in NYC

What are the reasons for energy simulations? System Development Building design improvement Economic benefits Budget planning

For budget planning Load vs. dry bulb temperature Measured for a building in Syracuse, NY Model Empirical model For average year use TMY2 =835890ton hour = Btu

Advance Energy Modeling with coupled energy and airflow Example: Night Cooling/Hybrid Ventilation The IONICA Office Building, Cambridge, UK

Night Cooling/Hybrid Ventilation: Requires combined Energy and airflow modeling

Night Cooling/Hybrid Ventilation: The IONICA Office Building, Cambridge, UK

Available software Which software to use: - Depends on project requirements - If you have a choice: the one which passed BETEST Be ready to conduct additional analysis based on your modeling skills

Structure of ES programs Solver Interface for input data Graphical User Interface (GUI) Interface for result presentation Preprocessor Engine Preprocessor ASCI file ASCI file

Modeling steps Define the domain Analyze the most important phenomena and define the most important elements Discretize the elements and define the connection Write energy and mass balance equations Solve the equations Present the result ES program Preprocessor Solver Postprocessor

EnergyPlus

Component-based simulation programs - Trnsys

ESPr University of Strathclyde - Glasgow, Scotland, UK Detailed models – Research program

1. Identify basic building elements which affect building energy consumption and analyze the performance of these elements using energy conservation models. 2. Analyze physics behind various numerical tools used for solving different heat transfer problems in building elements. 3. Use basic numerical methods for solving systems of linear and nonlinear equations. 4. Conduct building energy analysis using comprehensive computer simulation tools. 5. Evaluate performance of building envelope and environmental systems considering energy consumption. 6. Perform parametric analysis to evaluate the effects of design choices and operational strategies of building systems on building energy use. 7. Use building simulations in life-cycle cost analyses for selection of energy- efficient building components. Course Objectives