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ARCHITECTUR
October 8, 2014
ENERGIZED
Part 2:Energy Code Performance Path
MORNING OVERVIEW
2
• Key differences in performance path between ASHRAE and NECB
• Performance Path in Practice - Demo
What you will learn
• How to prepare a detailed energy model using the performance path
What you won’t learn
PERFORMANCE PATH
3
Flexible – Not Prescriptive!
Potential benefits outweigh the additional effort
Prescriptive, Trade-off may weight envelope too high
Model tells you best bang for the buck and provides a path for many design constraints
COMPLIANCE PATHS
4
LEED Canada NC 2009
MNECB 1997
ASHRAE 90.1-2007
App. G Rules
ASHRAE 90.1-2010
ECB Rules
NECB 2011
Code Compliance
LEED v4
NECB 2011 w/ mods
ASHRAE 90.1-2010
App. G Rules
WHICH CODE SHOULD I USE?
5
No “catch-all” answer Some buildings are “caught” by one of the codes Energy consultant should know ins/outs of the code
and make an informed “guess”
NECB VS. ASHRAE
6
NECB 2011 ASHRAE 90.1 2010
Envelope More Stringent -
HVAC & DHW Slightly More Stringent -
Lighting & Electrical Same Same
Trade off options For every section For some sections
Energy Modeling Based on “Energy Use” Based on “Energy Cost”
Mandatory provisions
None for Energy models Always applied
Glazing Ratio Calculation Only above grade
Includes below grade, provision for orientation
Performance Path ??? ???
COMPARISON STUDIES
7
DOES SOFTWARE MATTER?
8
GENERAL
9
• Schedules• Process Loads
0 3 6 9 12 15 18 21 240
0.1
0.2
0.3
0.4
0.5
0.6
0.7
0.8
0.9
1
NECB C Occupancy
Mon-Fri Sat Sun
Hour
Frac
tion
MANDATORY PROVISIONS
10
ASHRAE – Must always meet NECB mandatory requirements go
away with performance path
BUILDING ENVELOPE
11
NECB Glazing ratios, CoV correction
0 5 10 15 20 25$200,000
$205,000
$210,000
$215,000
$220,000
$225,000
$230,000
$235,000
$240,000
$245,000
$250,000
Energy Cost vs. Effective Wall R-value
ASHRAE MECHANICAL SYSTEMS
12
NECB MECHANICAL SYSTEMS
13
DISTRICT HEATING
14
No benefit or penalty for the “plant”
Plant usually compensates for poor envelope
Harder to comply with code
VENTILATION
15
NECB Use code rates ASHRAE Rates as per design Ventilation rates to be as per AHJ
(different than LEED!)
LIGHTING CONTROLS
16
Controls mandatory in ASHRAE (no credit) NECB has set “savings” for occupancy control – doesn’t
always mean reality Daylight benefit in NECB – modeled directly in
software
DOCUMENTATION
17
Consider early on! City of Vancouver Checklists Use of Schedule S
WHICH CODE?
18
ExamplesHigh Rise MURB with Electric BaseboardsHospitalData Centre
PERFORMANCE PATH IN ACTION
19
ARCHITECTUR
October 8, 2014
ENERGIZED
Parts 3 & 4:Responding to the Opportunity
OBJECTIVES
21
Identify the interrelated nature of architectural form on other building systems, energy and comfort
Extract more value from the integrated design process by incorporating data-driven guidance
Use key performance indicators to get early, real time feedback on design options
Realize more potential from your “energy modeler”
Enjoy the session
ENERGY ANALYSIS…WHO CAN DO IT?
22
Buildings are complicated
It’s more than just learning software
Opportunities for simplified analysis, but requires more judgment
Capacity bottlenecks
BETTER THAN BIM
23
WHERE DOES ANALYSIS FIT IN?
24
Goal SettingDiscovery
Interactive Loads and Comfort
Explorations
Optimization of Building Systems
Tuning and
Compliance
GOAL SETTING
25
Define
Measurable
Revisited
Accountable
PRIMARY GOALS
26
…
ADDITIONAL GOALS
27
Budget
Meet AHJ Requirements
Constructability
Environmental
Operating Costs
GOALS DESIGN CONSTRAINTS?
28
BUILDING ENVELOPE
29
STRONG RELATIONSHIP BETWEEN ARCHITECTURE AND THERMAL PERFORMANCE
HVAC OPTIONS
30
MissedOpportunities
Equipment Size System Type
Ventilation &
Occupancy
ARCHITECTURAL IMPACTS
31
Architectural
Form
Façade&
Glazing
Heat Loss Potential
HVAC Options
Condens. Risk
Solar Exposure
Orientation
Energy
Comfort Occ
DESIGN INTERACTIONS
32
Goals
Design Constraints
Architecture
Lighting
Mechanical
Envelope
INTEGRATED DESIGN EXPERIENCE
33
• When did it happen?• How far along was design?
Timing
• Who was there?• How were they engaged?
Players
• Did data inform the process?• Was there an active energy modeler?• Was any work done before hand?
Data
DATA DRIVEN GUIDANCE
34
• Detailed data takes time to produce• Simplified analysis cannot always be trusted• Past experience good, but is it validated?
The Challenge
• Real data based on anticipated direction• Visualize large data sets
The Solution
THE OPPORTUNITY
35
Goal SettingDiscovery
Interactive Loads and Comfort
Explorations
Optimization of Building Systems
Tuning and
Compliance
MASSING OPTIONS – OFFICE TOWER
36
BRAINSTORM
37
Massing?Elevations?Shading?
Tie Back to Goals
OUTCOMES
38
Energy• Too early• No M&E Yet• Possible for simple
projects
Loads• Heat, Cool, Light• Annual & Peak• No M&E Required• Need to know use
Comfort• What metrics are
valuable early?• Daylight contours
takes time• Glare indicators• Thermal Comfort
MAP IT
39
Optimizing Building Systems Through Energy Analysis
ENERGY MODELERS
41
TOP 5 QUESTIONS FOR ENERGY CONSULTANT
42
What are you doing here?
What code are you using and why?
What’s included in your R-value?
What matters?
How do these results compare with reality?
WHAT ARE YOU DOING HERE?
43
“Provide a fee for energy
modelling”
Write a scope that meets your
needs
What feedback to you want? When do
you want it?
Energy? Comfort? Daylight?
How will this consultant
help you do your job?
WHAT CODE ARE YOU USING?
44
Don’t chase the code
A good design will meet code, but…
Some codes penalize some buildings unfairly
Consultant should know the codes inside-out and recommend appropriately
WHAT’S WITH THE R-VALUE?
45
Is the R-value representative of the construction? What’s included in the R-value calculation? What source did you use? Have you seen the Building Envelope Thermal Bridging
Guide? Have you considered the details?
WHAT MATTERS?
46
Model Prescriptive?
Ask for a sensitivity analysis
Find out what matters to set yourself up for success throughout
design
WHAT DO THE RESULTS MEAN?
47
Can you put the energy use in context for me? How does this compare with other projects? Is the number similar to actual operating buildings? Is the end-use breakdown typical? Is it indicative of
anything odd?
BUILDING SYSTEMS OPTIMIZATION
48
Baseline – Office Tower Box, 60% Glazing, CW, no shading
Option 1 – Narrow, 20/20/40/20, H/V Shading Option 2 – Curve, 30/40/40/30, H Shading Option 3 – Box, 30/30/30/30, H/V Shading Option 4 – Curve, 60/60/60/40, H Shading
BUILDING ENVELOPE
49
BUILDING ENVELOPE
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Sample Effective Performance for “Standard” Construction Curtain Wall R4 to R9 Steel Framed R7 to R15 Concrete R6 to R12
Glazing Double Glazing with High and Low SHGC Triple Glazing with High and Low SHGC
M&E
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Standard VAV vs. 100% OA with Radiant Heating Efficiency Cooling Efficiency Heat Recovery Lighting Savings
MAP IT
52
CONCLUSIONS
53
Data driven conceptual design can help quantify the impacts of design decisions More options than you think!
Optimizing “form” leads to more options / cost effectiveness during building systems optimization
Energy models are more than that – take the opportunity to extract other important metrics like daylight, glare, and thermal comfort
Thank You