HIGH PERFORMANCE DESIGN Kristine Chalifoux, SEDAC Trade Ally Rally │Illinois │December 2014.
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Transcript of HIGH PERFORMANCE DESIGN Kristine Chalifoux, SEDAC Trade Ally Rally │Illinois │December 2014.
2
What will it take to achieve high performance?
A. Goal Setting: design & performance energy goals
Know where you are and where you want to go.
B. Pick the right team: identify an energy champion
C. Focus on energy: in design & construction
Know the most effective strategies
D. Verify energy goals: model & measure
E. Plan to maintain: training & ongoing verification
WHAT IS HIGH PERFORMANCE DESIGN?
Obtain at least one year’s worth of energy data on the building (two years or more is better).
Plot the energy consumption for each month versus heating degree days and cooling degree days.
Review the graphs for anomalies.
Here is a bank…
ENERGY USAGE ANALYSIS
www.degreedays.net/
July
Au
g
Se
p
Oct
No
v
De
c
Jan
Fe
b
Ma
r
Ap
r
Ma
y -
5,000
10,000
15,000
20,000
25,000
0
200
400
kWh CDD
kW
h
CD
D
July
Au
g
Se
p
Oct
No
v
De
c
Jan
Fe
b
Ma
r
Ap
r
Ma
y0500
1,0001,5002,0002,5003,0003,5004,0004,5005,000
0
200
400
600
800
1000
1200
1400Therms HDD
Th
erm
s
HD
D
Envelope Dominated: energy usage pattern tied to the climate, generally with some base load electrical and natural gas usage.
Internal Gain Dominated: energy usage pattern only slightly or not linked to the climate. Cooling load year-round.
Typically, small buildings are envelope dominated and large buildings are internal gain dominated – although this is not cast in concrete.
TWO TYPES OF BUILDINGS
ENERGY STAR® Target Finder was consulted for a comparison with similar buildings. Target Finder uses a large collection of building energy data to provide an estimate of an average building’s energy consumption, taking into account its location, size and use.
Energy Star Target Finder Score 1-100 www.Energystar.gov
UTILITY BILL ANALYSIS/BENCHMARKING
Annual Consumption Annual Costs Average Unit Cost
Electricity 504,000 kWh $ 50,249 87% $ 0.10 $/kWh Natural Gas 8,551 therms $ 7,236 13% $ 0.85 $/therm Total Facilities Area
Total: $ 57,485 15,753 ft2
Electricity Use Intensity
32 kWh/ft2/yr Gas Use Intensity
0.54 Therms/ft2/yr
Energy Use Intensity
163 kBtu/ft2/yr Energy Cost
Intensity $ 3.65 $/ft2/yr
Target Finder Results Bank Average ENERGY STAR Certified Energy Performance 31 Percentile 50 Percentile 70 Percentile Energy Use Intensity 163 kBtu/ft2/yr 104 kBtu/ft2/yr 82 kBtu/ft2/yr
050100150200250300350400450500
050,000
100,000150,000200,000250,000300,000350,000400,000
Nov
-10
Dec
-10
Jan-
11
Feb-
11
Mar
-11
Apr-
11
May
-11
Jun-
11
Jul-1
1
Aug-
11
Sep-
11
Oct
-11
Deg
ree
Day
s
kWh
kWh (3,753,262) CDD (1,237)
We know…
A school
No summer school
Heated
Cooled
Comfortable
TYPICAL DATA ANALYSIS – A SCHOOL…
REMEMBERWhen you shift a secondary axis you
are changing the story you tell.
0
200
400
050,000
100,000150,000200,000250,000300,000350,000400,000450,000500,000
Nov
-10
Dec
-10
Jan-
11
Feb-
11
Mar
-11
Apr-
11
May
-11
Jun-
11
Jul-1
1
Aug-
11
Sep-
11
Oct
-11
Deg
ree
Day
skWh
kWh (3,753,262) CDD (1,237)REMEMBERThe graph tells only part of the story! A school with minimal summer occupancy…
OR is the baseline electric use closer to~275,000 kWh?
April is a reasonable “guess” for baseline
monthly usage
High electric use in air conditioned schools - late spring/ early fall is not unusual as students return to classes and cooling demand can be high.
Base Load is typically lights, fans, pumps, plug loads, etc.
0
1,000
2,000
050,000
100,000150,000200,000250,000300,000350,000400,000450,000500,000
Nov
-10
Dec
-10
Jan-
11
Feb-
11
Mar
-11
Apr-
11
May
-11
Jun-
11
Jul-1
1
Aug-
11
Sep-
11
Oct
-11
Deg
ree
Day
skWh
kWh (3,753,262) HDDREMEMBERRemember to look for the unexpected!
Correlation with heating degree days likely means electric resistance heating somewhere in the building (i.e. teachers bringing in small space heaters)
0
500
1,000
1,500
2,000
0
1,000
2,000
3,000
4,000
5,000
6,000
Jun-10 Jul-10 Aug-10 Sep-10 Oct-10 Nov-10 Dec-10 Jan-11 Feb-11 Mar-11 Apr-11 May-11
Hea
tng
Deg
ree
Day
s
Mon
thly
The
rms
Nat'l Gas Usage (Therms) HDD
REMEMBERWhen you shift a secondary axis you are changing the story you tell.
Consider whether or not it is likely the baseline (base utility) natural gas use is ~2,500 Therms/month?
Base Load is typically DHW, pilot lights, etc.
100
300
500
700
900
1,100
1,300
1,500
0
1,000
2,000
3,000
4,000
5,000
6,000
Jun-10 Jul-10 Aug-10 Sep-10 Oct-10 Nov-10 Dec-10 Jan-11 Feb-11 Mar-11 Apr-11 May-11
Hea
tng
Deg
ree
Day
s
Mon
thly
The
rms
Nat'l Gas Usage (Therms) HDD
Or is it more likely that high natural gas use in summer indicates excessive use of ventilation system reheat – and the baseline (base utility) use is closer to 300 Therms/month.
REMEMBERWhen you shift a secondary axis you are changing the story you tell.
Don’t forget the power of interval data analysis when available!
Figure 1: 1/2-Hour Interval Metered Electric Energy Demand – November 2010
0
20
40
60
80
100
120
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160
12:00 AM to 12:30 AM
1:00 AM to 1:30 AM
2:00 AM to 2:30 AM
3:00 AM to 3:30 AM
4:00 AM to 4:30 AM
5:00 AM to 5:30 AM
6:00 AM to 6:30 AM
7:00 AM to 7:30 AM
8:00 AM to 8:30 AM
9:00 AM to 9:30 AM
10:00 AM to 10:30 AM
11:00 AM to 11:30 AM
12:00 PM to 12:30 PM
1:00 PM to 1:30 PM
2:00 PM to 2:30 PM
3:00 PM to 3:30 PM
4:00 PM to 4:30 PM
5:00 PM to 5:30 PM
6:00 PM to 6:30 PM
7:00 PM to 7:30 PM
8:00 PM to 8:30 PM
9:00 PM to 9:30 PM
10:00 PM to 10:30 PM
11: 00 PM to 11:30 PM
1/2-Hour Interval Metered Electric Energy Demand (kW) November 2010
Monday November 1, 2010
Tuesday November 2, 2010
Election Day, school is closed. But some portions are open for polling.
TOP TEN ENERGY STRATEGIESForm & Environment
1. Orientation & Form
2. Insulation
3. Air Sealing
Loads
4. Lighting
5. Loads
Heating, Ventilating, & Air Conditioning
6. Heating
7. Cooling
8. Motors & Pumps
9. Building Automation
10. Commissioning
EXTRA CREDIT: After implementing all of
these, consider renewables such as solar and wind.
CASE STUDY
Science & Technology magnet school Replaces existing building
He
atin
g
Co
olin
g
Pu
mp
s/F
an
s
Inte
rio
r L
igh
ting
Plu
g L
oa
ds0
100,000
200,000
300,000
400,000
500,000
Baseline Annual kWh Proposed Annual kWh
kW
h
Base Case Annual
kWhProposed Annual
kWhSavings Annual
kWh% Saved % Total
Heating 437,167 25,197 411,970 94% 45%
Cooling 74,963 31,606 43,357 58% 5%
Pumps/Fans 72,140 166,560 -94,420 -131% -10%
Interior Lighting 123,298 104,357 18,941 15% 2%
Exterior Lighting 18,505 18,505 0 0% 0%
Plug Loads 200,509 200,509 0 0% 0%
Total 926,582 546,734 379,848 41% 41%
Orient buildings on the east-west axis (+/- 10°)
Reduce west facing glass
Shade south glazing
Take advantage of, or block, prevailing winds
Orientation makes a difference in energy use!
ORIENTATION & ENVIRONMENT
East West Axis South overhangs Northern and southern windows
CASE STUDY ORIENTATION
0° 90° 180° 270°$70,000
$72,000
$74,000
$76,000
$78,000
$80,000
$82,000
…faces west
Beware of value engineering!
Shading devices compensate for the heat gain from large banks of windows, only to be eliminated later in order to cut up-front costs. If the windows themselves are not re-designed, the result is visual discomfort from glare and higher energy costs.
ORIENTATION “DON’TS”
Exceed codeWall and roof insulation levels
Continuous insulation
Windows Percent of wall area Low-e coating
Reduced infiltration Air sealing Air barrier Vestibules
Envelope commissioning
ENVELOPE
Air infiltration is unwanted air flow into and out of the building caused by leakage paths and pressure differences between inside and outside of the building.
Openings at the top and bottom of the building are the most important to seal.
plumbing chases wiring recessed lights chimney enclosures sill plate look above a recessed ceiling ducts in unconditioned areas surprises that you will find
AIR SEALING
SEALING THE ENVELOPE
Pre-Retrofit Post Air Sealing
From SEDAC report
Current condition
Wall to Roof Junction Air Sealing
STACK EFFECT
Positive pressure (with reference to outside)
Neutral pressure plane
Negative pressure (with reference to outside)
Photo Credit: David Keefe, Vermont Energy Investment Corporation
Don’t let this happen to your building!
R-18 to R-24 walls3” continuous insulation (polyiso)
R-37 roof insulation6” continuous insulation (polyiso)3” minimum at drains
Windows U-0.27, SHGC-0.31
Vestibules
Designed with heat exchanger to make up for reduced air infiltration
CASE STUDY ENVELOPE
Occupants were cold
No continuous insulation
Don’t underestimate the impact of thermal bridging
ENVELOPE “DON’TS”
28
Avoid these common pitfalls
• Assemblies with significant thermal bridging
MORE ENVELOPE “DON’TS”
29
Avoid these common pitfalls
• Assemblies with significant thermal bridging
MORE ENVELOPE “DON’TS”