Digital Environmental Design: Modeling Basics

• Digital Environmental Design involves simulating/modelling environmental and energy performances in the built environment.
• It uses software to model and simulate environmental performance, covering thermal, visual, and acoustic aspects.
• Also considers energy performance, including consumption for heating, cooling, and lighting in buildings or urban areas.
• The lecture covers building environmental and energy modelling basics, main functions of building and energy models, and applications of modelling tools.

Basic Knowledge

• Creating building models for environmental and energy performance requires considering desired results, design questions, tool costs, and simulation speed.
• Digital tools used early in building design require considering building form, orientation, window areas, along with shading devices that affect environmental and energy performance.
• Digital tools in detailed design require optimizing insulation levels plus glass and frame specifications, and glare/light quality.
• Key factors in designing building service systems for building engineers are system type selection relative to building loads, specific design decisions like equipment efficiencies, and air distribution system design.
• Energy consumption is a key result, including annual consumption, cost, and CO2 emissions.

Main Functions

Digital tools facilitate design in several areas:

• Site analysis covers site planning on a large scale by checking for solar access or analyzing wind/airflow in outdoor spaces.
• Building component analysis and design uses digital tools to test building features like insulation and window configurations + façade systems.
• Building thermal analysis uses tools to test design solutions based on thermal comfort and performance.
• Lighting design and analysis tests design solutions based on visual comfort and lighting conditions.
• Ventilation design and analysis uses tools that design ventilation systems for good air quality and airflow/temperature.
• HVAC design employs digital tools to design building service systems, including heating, ventilation, & air conditioning
• Energy performance and CO2 emissions target overall performance, with digital tools testing designs.

Applications

Popular tools in the building industry:

• Revit + Insight = an important BIM tool.
• Revit is a BIM tool and Insight is a plugin for Revit, allowing for environmental and energy performance simulation.
• Can be downloaded from www.autodesk.co.uk/products.
• It provides whole energy performance and cost analysis to identify key energy performance drivers like lighting power density, HVAC systems, and glazing properties.
• Millions of potential design scenarios can be quickly compared, visualizing the impact of orientation, envelope, WWR, lighting equipment, schedules, HVAC, and PV usage.
• Using EnergyPlus, REVIT + Insight analyze heating and cooling systems based on energy calculations.
• Solar Analysis tracks how much building energy can be offset with PV solar panel design using shading design.
• Lighting Analysis for Revit is integrated into Insight for LEED analysis and customized lighting settings, including date/time selection, plane specification, and threshold, to generate illuminance renderings with electric lighting.
• DesignBuilder + EnergyPlus is a commercial software widely used.
• A link to DesignBuilder + EnergyPlus is found here: https://designbuilder.co.uk/software/for-architects.
• The main simulation engine is EnergyPlus.
• A link to EnergyPlus is found here: https://energyplus.net/.
• It provides a holistic view of performance for fast confident decisions.
• Functions of DesignBuilder include 3D Modeller, Visualization, Simulation (EnergyPlus), Daylighting, HVAC, Cost calculation, LEED, Optimization, Scripting, CFD, and Certification.
• Designs offer energy, daylighting, and airflow performance.
• IES Virtual Environment (IESVE) translates building physics into technical info and visualisation, essential for architects/engineers.
• A commercial software, it can be found here: www.iesve.com.
• Functions of IES VE: 3D Modelling & BIM Interoperability, Energy Simulation, Solar Shading, Daylight Simulation/Lighting Design (Radiance), HVAC System Sizing/Optimization, Airflow (CFD), LEED, and Certification.
• IES VE uses APACHESIM, not EnergyPlus, as its simulation engine.
• SketchUp + OpenStudio is a free tool.
• As a SketchUp plugin, OpenStudio supports building energy modeling using EnergyPlus and Radiance: https://www.radiance-online.org/.
• The free plugin can be found here: www.openstudio.net.
• This tool assists design based on energy and environmental performance simulation, including heating, cooling, ventilation, and lighting, to visual design.
• Rhino + DIVA is a commercial tool.
• DIVA-for-Rhino is a daylighting and energy modeling plug-in for the Rhinoceros - NURBS modeler, requiring both Rhino and then DIVA to be installed.
• Rhino = www.rhino3d.com
• DIVA = http://diva4rhino.com/
• DIVA-for-Rhino facilitates environmental performance evaluations, including Radiation Maps, Photorealistic Renderings, Climate-Based Daylighting Metrics, Glare Analysis, LEED/CHPS Compliance, and Energy/Load Calculations.
• It supports building energy modeling with EnergyPlus and Radiance: https://www.radiance-online.org/.

Tools for parametric study

• Grasshopper 3D + DIVA is used for environmental analysis.
• Ladybug is used for environmental analysis.
• Honeybee is used for environmental analysis.
• These tools use EnergyPlus and Radiance as simulation engines.

Key simulation workflow (Energy and Lighting)

• Step 1: Build a new project.
• Step 2: Define the location by loading weather data.
• Step 3: Model building and architectural features.
• Step 4: Set building characteristics like U values and g value.
• Step 5: Set environmental properties, like service systems and occupancy.
• Step 6: Run simulation.