utilizing energy modeling to reduce operating costs
TRANSCRIPT
Integrated Design Solutions Architecture, Engineering, Interiors & Technology
UTILIZING ENERGY MODELING TO REDUCE
OPERATING COSTS
Bruce Snyder, CEM, CEA, LEED AP BD + C
October, 2011
Just the facts:
Source: Energy Information Administration, U.S. Dept. of Energy. June 2008.
Commercial Buildings in the U.S. are
responsible for:
20% of the total energy consumption
35% of electrical consumption
18% of CO2 emissions
17% of all green house gas emissions
Presentation Overview
What is a Whole Building Energy Model?
Who uses them and why?
When to use it.
Are they accurate?
Software Options.
Efficiencies in Design.
Top Ten ECM list.
What is a Whole Building Energy Model?
It is a computational (mathematical) representation
of a physical structure and the equipment within
that can be set to operate in a particular climate to
produce energy consumption and cost output.
The model can be for an existing building or new.
It is not a physical scale model
is not intended for aesthetic
evaluations.
What is a Whole Building Energy Model?
It is not computational fluid
dynamics (CFD).
Not cost effective at analyzing
individual energy conservation
measures (ECM’s) piecemeal.
It is used for individual ECM
assessment as part of a
comprehensive analysis.
What is a Whole Building Energy Model?
Effectively analyzes multiple
ECM’s and design features with
interactions.
BAS Modifications
Active Chilled Beam Condensing Boilers Lighting retrofit
Creating the Model.
Before you start:
Obtain all record documents relative to the design, construction, usage, and operation of the building.
Walk the entire building. Including the roof!
Photograph as much as possible/entire building exterior.
Obtain 12-24 months of utility bills. Including water.
Interview the building engineers and users.
Creating the Model.
The difference between 3D graphical model and non-graphical.
Select the building location/weather station.
Create the footprint and input spaces.
Input the envelope details, windows, roof, walls, skylights, etc.
Creating the Model.
Input the HVAC systems.
Source of heat, source of cooling, heat recovery elements, equipment schedules, temperature and static pressure set points, etc.
Creating the Model.
Input the internal load components.
Input the mechanical terminal equipment. Enter features, pressure dependant/independent, static reset, occupancy control, DCV, etc.
Thermotron Typical Terminal Unit
Creating the Model.
Input plant data. Chillers, boilers, remote plants,
district heating or cooling, etc.
Misc. fuel use.
Input utility rates.
Utility Bills
Creating the Model.
Most programs accommodate complex utility rate
structures.
Rate
Type
Demand
Usage
Delivery
Creating the Model.
Scan Floor Plan into Micro Station.
Un-scaled owner furnished key plan
scanned into AutoCAD and traced
Scaled drawing in eQuest
Creating the Model.
Create Zoning.
Interior zoning
Blue- Current Zone
Green- Already
Zoned
Yellow- To be
Zoned
Creating the Model.
Data entry screen- HVAC systems.
Wizard mode
Detailed mode
Creating the Model.
Data entry screen- hover & help information.
Description
appears when you
hover the curser
over the input value
Creating the Model.
Data entry screen- hover & help information.
Direct link to
help
information
Creating the Model.
Create roof and walls.
Roof details
Red Text is
user input
Green Text
is Default
Creating the Model.
Window data and locations.
Custom window locations
Window characteristics
Creating the Model.
Occupancy schedules. Seasonal, daily, hourly.
Season Definitions – Wizard Mode
Occupancy Schedule – Wizard Mode
Creating the Model.
Utility Rate input screen.
Creating the Model.
Model example.
Satellite picture 3D Model
Creating the Model.
Model example.
3D Model
Green indicates
earth contact
Tan indicates
above
unconditioned
space White
indicates
above
conditioned
space
Creating the Model.
Model example.
Satellite picture 3D Model
Creating the Model.
Model example.
Satellite picture
3D Model
Creating the Model.
Sample outputs.
Annual energy consumption by end use Monthly energy consumption by end use
797,640 KWH 4,975.6 MBtu
Creating the Model.
Sample output comparing multiple energy conservation measures.
Monthly total energy consumption comparison Annual utility bills by rate comparison
Who uses Energy Models and why?
Architects, designers, engineers, and building
performance analysts.
Certified Energy Managers and LEED AP’s.
Performance Contract Companies aka
Energy Services Companies (ESCO’s).
Building owners and operators.
ASHRAE, ICC, The DOE, and the EPA.
Who uses Energy Models and why?
Why?
To determine the optimum design
strategy/Explore different options.
To support “evidence-based design.”
To determine ECM paybacks.
To meet ASHRAE Level (2 &) 3 Energy Audit requirements.
To meet the Rebuild Michigan Comprehensive Technical Energy Analysis (CTEA) requirements.
To meet the Energy Works Michigan Energy Efficiency (EE) grant program requirements.
Who uses Energy Models and why?
To meet State & Federal grant requirements.
ASHRAE Standard 189.1 Design of High-
Performance Green Buildings.
To meet the requirements for Internal Revenue
Service (IRS) Code 179D Tax Credits.
To qualify for LEED Credit EA1,
Optimize Energy Performance.
Revenue Service (IRS) Code 179D Tax Credits
A tax credit of up to $1.80/SF is available to owners/tenants/designers of new or existing commercial buildings that are constructed or renovated to save 50% of heating, cooling, ventilation, water heating and lighting energy cost of a building that meets ASHRAE Standard 90.1-2001.
Envelope 10%, lighting 20%, HVAC 20%.
Buildings placed into service from 1/1/2006 through 12/31/2013.
Key Provisions:
Certifications must be done by licensed engineers not “related” to the taxpayer taking the deduction.
Certification must be in accordance with Appendix G of ASHRAE Standard 90.1-2004.
The certification must include a field investigation to confirm savings goals.
Certifiers must provide the building owner with the list of energy efficient features and projected annual energy costs.
Revenue Service (IRS) Code 179D Tax Credits Revenue Service (IRS) Code 179D Tax Credits
LEED- 2009, EA Credit 1,
Optimize Energy Performance
When to use a Whole Building Energy
Model?
Leve
l of
Effo
rt/La
bor
Hours
Programming
Size, Site Analysis, Building Orientation, etc.
Schematic Design
Window to Wall Ratios, HVAC & Ventilation Options, Day lighting, Smart building features
DD & CD’s
Equipment Sizing, LEED Documentation, Equipment Performance Requirements
Design Phase
Are They Accurate?
“This degree of scatter suggests significant room for improvement in
energy use predication accuracy on an individual project basis.”
Ref: New Building Institutes “Energy Performance of LEED for New Constructed Buildings”
Are They Accurate?
Ref: New Building Institutes “Energy Performance of LEED for New Constructed Buildings”
Are They Accurate?
Major contributors to model inaccuracies:
Experience of the architect or engineer developing
the model.
Poor communication with the owner/ bad
information from the owner/ lack of complete
information from the owner.
Incomplete owner interview process.
Incomplete field survey.
Are They Accurate?
Major contributors to model inaccuracies cont’d:
Deviation from average weather data in the
modeling program (without DD correction).
Unanticipated change in use from it’s original intent.
Limitations of the existing modeling programs.
Software Options
U.S. DOE Building Energy Software Tools Directory
lists 387 unique software programs.
Qualified Software for the DOE Tax Credits:
DOE 2.2, EnergyGauge, EnergyPlus, EnergyPro,
EnerSim, eQuest, Green Building Studio, Carrier
HAP, IES, Trane Trace 700.
Software Options
The Race to Integrate:
In 2008, Bentley Systems (MicroStation) bought energy-
analysis software maker Hevacomp Ltd. and secured
right’s to distribute Environmental Design Solutions Ltd.
(EDSL).
Also in 2008, Autodesk (AutoCAD) bought Green Building
Studio and Ecotect with intent to create a stream line from
Revit to energy analysis.
In 2009, Graphisoft released EcoDesigner which is built
into ArchiCAD billed to be one-click analysis.
Efficiencies in Design
The goal is to move from BIM to building energy analysis without substantial duplication of effort.
Green Building XML (gbXML).
gbXML is an open data exchange protocol used to accomplish this.
Efficiencies in Design
Using Google SketchUp, users can conduct basic building energy analysis with plugins from IES VE-Ware, EnergyPlus and Greenspace Research’s Demeter.
Must add attributes to the geometry.
With the appropriate plugin, SketchUp is able to import and export gbXML files.
Efficiencies in Design
IES VE can be used as a SketchUp plug-in that works off of a toolbar that connects to IES’s tools: IES VE-Ware, IES VE-Toolkits, and the full Virtual Environment.
EnergyPlus is a building energy simulation software created by the U.S. DOE. This is also can be a plug-in to SketchUp used to model heating, cooling, lighting, ventilation etc.
Efficiencies in Design
Autodesk Ecotect is a concept-to-detail sustainable design and analysis tool intended to improve performance of existing and new building designs.
Provides online energy, water, and carbon-emission analysis capabilities for visualizing and simulating building performance. Covers solar effect, shadows, reflections, daylighting etc.
Solar radiation analysis as completed in Autodesk Ecotect.
Closing Thoughts
Whole Building Energy Modeling should have a major impact on any renovation or new building design.
It should start early in the design process and progress through each stage.
It can be a very accurate predictor of future costs and energy consumption if done correctly.
Selecting the correct software and file sharing will reduce duplication of effort by the design team.
Energy Modeling Seminars
AEE – 3 Day Seminar on The Fundamentals of Building Energy Simulation at the Navy Pier in Chicago, IL Oct 11-13, 2011.
University of Wisconsin, Energy Modeling for High Performance Buildings with Emphasis on eQuest and LEED Projects, June 20-21, 2012 in Madison, WI.
The Energy Center University, eQuest Training Series- Introduction & intermediate eQuest, LEED Energy Modeling with eQuest, Nov 1-3, 2011 at Holiday Inn, Madison WI.
Top Ten ECM List
1. Steam Trap Audit Program
2. Variable Frequency Drive’s on everything
3. DDC Retrofit/Upgrade
4. Demand Controlled Ventilation
5. Lighting Efficiency Upgrade
6. Lighting Controls
7. District wide temperature set point standards
8. Data Center Improvements
9. Retro-commissioning
10. Improved plug load efficiencies
Contact Information:
Bruce Snyder
1441 W. Long Lake
Troy, MI 48098
Phone: 248-823-2174
Email: [email protected]
Questions???
Integrated Design Solutions Architecture, Engineering, Interiors & Technology