Copyright  2011 EnergyPlus and Model Outputs CEE 243 CEE 243:Week 5 Introduction to EnergyPlus & Model Outputs E+ model of Y2E2 James O’Donnell Ph.D.Copyright  2011 EnergyPlus and Model Outputs CEE 243 Agenda 1. EnergyPlus Concepts 2. Examples 3. Ideal Industry Integration of Simulation 4. Conclusions 5. Homework 2Copyright  2011 EnergyPlus and Model Outputs CEE 243 Big ideas • creating simulation models requires a process to model the facility and populate assumptions about building thermal properties – Best to create analyses with careful attention to a well-established process • E+ allows flexible assumptions and simulation outputs. This session shows: – The principles behind EnergyPlus – Visualization of important E+ Outputs – Other possible simulation outputs 3Copyright  2011 EnergyPlus and Model Outputs CEE 243 EnergyPlus Concepts • E+ assumes – Time dependent heat conduction • Conduction through building surfaces calculated with conduction transfer functions • Heat storage and time lags – Air Migration between zones • Air exchange follows a nodal model – Only analyzes what is explicitly described • Missing wall does not let air in • Missing roof does not let sun in 4Copyright  2011 EnergyPlus and Model Outputs CEE 243 EnergyPlus Concepts (cont’d) • Heat balance loads calculation (one of two load calculation methods recommended by ASHRAE) • Moisture balance calculation • Simultaneous building/systems solution • Sub-hourly time steps • Modular HVAC system simulation • WINDOW 6 methodology 5Copyright  2011 EnergyPlus and Model Outputs CEE 243 EnergyPlus Concepts (cont’d) • Simple input/output file structures • No surface, zone or system limits – Defaults to 50 coils per HVAC loop – Can be increased • Links to other software – COMIS, wind-induced airflow – TRNYSYS, Photovoltaics 6Copyright  2011 EnergyPlus and Model Outputs CEE 243 EnergyPlus Structure 7 Note: these UIs are not available in mid-2011Copyright  2011 EnergyPlus and Model Outputs CEE 243 Integrated Simulation Manager • Fully integrated simulation of loads, systems and plant – Integrated simulation allows capacity limits to be modeled more realistically – Provides tighter coupling between the air- and water-side of the system and plant 8Copyright  2011 EnergyPlus and Model Outputs CEE 243 Integrated Simulation Manager (cont’d) 9 Note: these arrows represent two-way information flowCopyright  2011 EnergyPlus and Model Outputs CEE 243 Today’s Learning Itinerary • Run Control • Geometry • Internal Loads • Systems • Control 10Copyright  2011 EnergyPlus and Model Outputs 11 CEE 243 Process to create an EnergyPlus model BIM GST IDF Generator (LBNL project) IDF Geometry IFC Geometry IDF Setpoints Schedules IDF HVAC systems IDF Controls Architectural drawings Mechanical drawings EPW Weather file Field surveys Manufacturer product data Predicted data Material library Data Format Legend: Model or data Process Tool Information Flow Design BIM Analytical BIMCopyright  2011 EnergyPlus and Model Outputs 12 CEE 243 ExamplesCopyright  2011 EnergyPlus and Model Outputs CEE 243 Examples 1. Example 1: Geometry Only 2. Example 2: Manually modify to add insulation for one zone 3. Example 3: Load Determination 4. Example 4: HVAC System 13Copyright  2011 EnergyPlus and Model Outputs CEE 243 Example Description • 1 zone building with a door and a window on the south façade. • Construction Descriptions – Walls, Floors, Ceiling (Cavity Wall) – Window (Single Pane) • Create in ArchiCAD • Save as IFC • Run Through GST • GST Output = Energyplus input file. 14Copyright  2011 EnergyPlus and Model Outputs CEE 243 Run Control Assume: • Design Day (San Jose) • Design Day Only • No annual simulation 15 4/28/2011 CEE243Copyright  2011 EnergyPlus and Model Outputs CEE 243 Simple Model Setup • Box model with concrete walls low thermal mass (Shown in Sketch Up). – 1 South Facing Window – 1 South Facing Door • Necessary Inputs • Design Day Data (Santa Clara). 16 4/28/2011 CEE243Copyright  2011 EnergyPlus and Model Outputs CEE 243 Simple Model 1 Output • Outputs with an RVI file • Look at zone temperature • Conductive heat transfer • Output Contains OA DB, Zone DB, Perhaps Wall Conductance 17Copyright  2011 EnergyPlus and Model Outputs CEE 243 Example 1: Output (2 Two Design Days) 18 Example 1: AO DB Temp V Zone DB Temp Temp (C) -505101520253035Environment:Outdoor Dry Bulb [C](Hourly) TESTZONE_001:Zone/Sys Air Temperature [C](Hourly)Note: zone temp swings far from assumed functional intent of 23oC ~= 74oFCopyright  2011 EnergyPlus and Model Outputs CEE 243 Simple Model 2 • Add insulation to the walls • Add Triple Glazing • Compare with previous results 19Copyright  2011 EnergyPlus and Model Outputs CEE 243 Example 2: Output (2 Design Days) 20 05101520253035Temperature C Example 2: AO DB Temp V Zone DB Temp Environment:Outdoor Dry Bulb [C](Hourly) TESTZONE_001:Zone/Sys Air Temperature [C](Hourly)Note: zone temp stays close to assumed functional intent of 23oC ~= 74oFCopyright  2011 EnergyPlus and Model Outputs CEE 243 Simple Model 3 • Zone sizing • System sizing • Highlight Max heating and cooling loads and max heating Load 21Copyright  2011 EnergyPlus and Model Outputs CEE 243 Simple Model 3 Outputs: Zone Sizing 22 02000000400000060000008000000100000001200000014000000Sensible Load (W) Zone Sensible Load: Alternative 1 TESTZONE_001:Zone/Sys Sensible Heating Energy [J](Hourly) TESTZONE_001:Zone/Sys Sensible Cooling Energy [J](Hourly)Note: heating in winter Note: cooling in summerCopyright  2011 EnergyPlus and Model Outputs CEE 243 Example 3: Impact of moving building from San Jose to San Francisco 23 02000000400000060000008000000100000001200000014000000 Load (J) Design Days: Zone Sensible Loads TESTZONE_001:Zone/Sys Sensible Heating Energy [J](Hourly) TESTZONE_001:Zone/Sys Sensible Cooling Energy [J](Hourly)Note: heating in winter slightly less Note: cooling in summer slightly lessCopyright  2011 EnergyPlus and Model Outputs CEE 243 Systems Definition • Engineering Description (On Board) • E+ Description (On Board) • Additional inputs – Setpoint Schedules, – Branches etc. 24Copyright  2011 EnergyPlus and Model Outputs CEE 243 Example 4: System Temperatures 25 0510152025Temperature C System Dry Bulb