Transcript Slide 1

Development of the Potential Energy
Savings Estimation (PESE) Toolkit
Jingjing Liu,
Juan-Carlos Baltazar and David E. Claridge
17th Symposium for Improving Building Conditions in Hot and Humid Climates
Energy Systems Laboratory
Texas A&M University
August 2010
Overview

Introduction

Methodology

PESE Toolkit

Example of Application

Conclusions
17th Symposium for Improving Building Conditions in Hot and Humid Climates
2
Introduction
17th Symposium for Improving Building Conditions in Hot and Humid Climates
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Problem Statement

Some form of screening is needed to determine
whether there is sufficient potential for savings to
justify a EBCx assessment.
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Approach to Problem

To make it a useful tool in EBCx, further
improvement and testing of the methodology is
necessary, which requires development of a prototype
computer tool.
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Methodology
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Review of Methodology

Compares actual energy cost with minimized cost
from a simulation based on modified bin method
 Minimum energy use cost determined with
– A model representing system performance
 weather conditions, load calculation, air-side system simulation
– The numerical procedure for energy cost minimization
 Uses sequential exhaustive search
 Generates the input parameter values for minimum energy cost
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Review of Methodology
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Review of Methodology
Potential Energy Cost Savings =
Actual Energy Cost – Minimum EnergyCost
Energy Cost = (ELE CostLTEQ + ELE CostFANP) +
CHW Cost + HHW Cost
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Improvements on Methodology

Optimization Parameters
– Five parameters: exterior and interior zone room temperature
set points, cold deck and hot deck (only for dual duct)
leaving air temperature set points, outside air flow rate.

Space load calculation
– Based on modified bin method
– Enabled by optimizing room temperature
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
Buildings with Multiple Types of Systems
– Permitted

AHU Shutdown Simulation
– A new empirical method is developed and used for
estimating the energy use during the AHU shutdown and
start-up period.
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PESE Toolkit
(Potential Energy Savings Estimation)
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Overview of PESE Toolkit

Purpose: to test the improved methodology
 Developed with Excel VBA 2003
 Important features:
– User friendly input interface;
– Space load calculation is included;
– User can decide which optimization parameters to activate;
– Simulation models of four common HVAC systems;
– Comprehensive output for each bin and illustrated in plots.

Input and output
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Name
City
Latitude
Orientation (Wall# 1)
Length
Width
Height
Above ground floors
Has Basement
Basement conditioned
A tot
SYSTEM INFORMATION
System Type
SDVAV
Reheat Type
Hot Water
Preheat Type
Hot Water
Has Economizer
FALSE
AHU shut off
FALSE
Fraction of A e
100.0%
General
Sanders Corps of Cadets Center
College Station
N
30 °
NE
180 ft
110 ft
15 ft
1
Ae
FALSE
FALSE
2
19,800 ft
2
7,800 ft
Ai
2
12,000 ft
4
1
3
TCL
110
0.1
0.2
Fraction of A i
100.0%
Zone T set point during occupied hours
Te_ocp
°F
2
Ti_ocp
°F
Zone T reset point during unoccupied hours
Te_unocp
°F
##### of A tot
Ti_unocp
##### of A tot
V TD
Internal Heat Gain
120
TCL/THL (°F)
BUILDING INFORMATION
THL
100
90
80
70
60
50
0
20
40
°F
Ve
Vi
Ocpi
20 pep
TCL (setpoint 1)
64 °F
cfm
@
TOA1=
25 °F
AveOcpFactor (Ocp)
1.00
TCL (setpoint 2)
57 °F
@
TOA2=
65 °F
AveOcpFactor (Unocp)
0.10
THL (setpoint 1)
95 °F
@
TOA1=
30 °F
THL (setpoint 2)
80 °F
30 hp
@
TOA2=
70 °F
Weather
67.65
33.60
P SF-rated
P RF-rated
FPS_July
0.72
OA controlled by
FPS_January
0.48
XOA,min_ocp
Tpc
Tph
To,des
U-wall
107 °F
27 °F
86 °F
Envelope
2
0.09 Btu/(h∙ft ∙°F)
100 120
cfm
20 pep
54 kW
25 kW
80
27,545 cfm
Ocpe
LTEQ (Ocp)
LTEQ (Unocp)
60
TOA (°F)
0 hp
VOAmin
VOA max
cfm
XOA,min_unocp
V OA,min_ocp
cfm
V OA,min_unocp
VAV systems
VAV mechanism Variable Speed Drive
cfm
V e,min_ocp
3,820 cfm
V e,min_unocp
0 cfm
V i,min_ocp
3,600 cfm
V i,min_unocp
0 cfm
U-window
U-roof
U-ground
A win/A wall 1
1.00 Btu/(h∙ft 2∙°F)
0.05 Btu/(h∙ft 2∙°F)
0.05 Btu/(h∙ft 2∙°F)
25.0%
OPTIMIZATION OPTIONS
Variables
Select
A win/A wall 2
15.0%
Te
TRUE (°F)
70 −
78
9
65
−
85
11
A win/A wall 3
25.0%
Ti
TRUE (°F)
68 −
72
5
65
−
85
11
A win/A wall 4
15.0%
TCL
TRUE (°F)
55 −
70
16
55
−
70
16
THL
FALSE (°F)
80 −
115
16
80
−
115
16
600 −
4,500
11
0
−
4,500
12
A sky lights
2
0 ft
Ocp: range & grid Unocp: range & grid
VOA
TRUE (cfm)
0.20
ELE Price
0.092 $/kWh
0.25
CHW Price
9.602 $/MMBtu
0.00
HHW Price
13.099 $/MMBtu
SC 1
0.45
SC 2
0.15
SC 3
SC 4
SC skylights
Wall color
Medium colored
RHz1
10 %
Roof color
Dark colored
RHz2
60 %
17th Symposium for Improving Building Conditions in Hot and Humid Climates
ESTIMATE POTENTIAL ENERGY
COST SAVINGS
17
Bin data input in the simulation
BIN DATA INPUTS
Outside air
temperature
OCCUPIED PERIOD
(°F)
TOA
27
32
37
42
47
52
57
62
67
72
77
82
87
92
97
102
107
Outside air
humidity ratio
wOA
0.001948
0.002618
0.003551
0.004116
0.004348
0.005150
0.005589
0.006464
0.008619
0.010431
0.012683
0.014488
0.014880
0.014615
0.013313
0.012134
0.012752
Zone relative Hours of
Measured ELE
humidity
occurrence consumption
(%)
RHOA
65.2
69.5
77.1
73.4
64.1
62.9
56.8
54.9
61.3
62.3
63.9
61.8
54.0
45.4
35.5
27.9
25.2
(hr)
HOURS
2
5
33
56
110
112
163
192
290
351
382
374
290
282
140
11
1
(kWh)
ELE_Meas
89
255
1,998
3,651
7,204
7,262
10,795
12,654
19,161
23,177
25,705
25,465
20,511
20,020
10,176
816
75
Measured CHW
consumption
Measured HHW
consumption
(kBtu)
CHW_Meas
241
912
6,122
11,484
25,093
27,096
41,775
52,277
85,079
109,389
130,655
137,366
116,138
123,951
66,872
5,560
494
(kBtu)
HHW_Meas
410
1,246
7,843
12,516
21,783
21,622
29,424
31,724
42,959
47,778
44,621
37,379
25,384
22,089
11,207
1,003
106
Measured CHW
consumption
Measured HHW
18
consumption
BIN DATA INPUTS
Outside air
Outside air
Zone relative Hours of
Measured ELE
temperature
humidity
ratio
humidity
occurrence
consumption
17th Symposium for Improving Building Conditions in Hot and Humid Climates
87
92
97
102
107
0.014880
0.014615
0.013313
0.012134
0.012752
54.0
45.4
35.5
27.9
25.2
Bin data input in the simulation
290
282
140
11
1
19,890
19,748
10,014
804
75
122,998
126,638
65,899
5,423
521
8,671
6,673
2,439
123
5
BIN DATA INPUTS
Outside air
temperature
UNOCCUPIED PERIOD
(°F)
TOA
27
32
37
42
47
52
57
62
67
72
77
82
87
92
97
102
Outside air
Zone relative Hours of
Measured ELE Measured CHW Measured HHW
humidity ratio
humidity
occurrence consumption
consumption
consumption
wOA
0.002106
0.002643
0.003461
0.003995
0.004601
0.005675
0.007088
0.008834
0.010686
0.013023
0.015470
0.015346
0.014747
0.014614
0.012826
0.010645
(%)
RHOA
70.5
70.1
75.2
71.3
67.8
69.3
71.9
74.8
75.7
77.5
77.6
65.3
53.5
45.3
34.2
24.5
(hr)
(kWh)
(kBtu)
(kBtu)
HOURS ELE_Meas CHW_Meas HHW_Meas
11
374
1,675
2,782
76
2,586
12,942
18,657
186
6,329
35,019
44,282
303
10,310
62,495
69,893
378
12,861
84,761
84,393
428
14,563
103,669
92,387
445
15,141
115,788
92,761
538
18,305
149,681
108,163
646
21,980
190,560
121,143
813
27,662
246,615
134,016
1,030
35,046
321,319
112,886
532
18,101
167,240
45,876
298
10,353
97,964
21,916
205
7,369
72,233
13,797
82
3,052
30,520
5,007
10
386
3,913
548
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PARAMETERS
FLOW FRACTION
AIRSENSIBLE
SAVINGS
LOADS
CONSUMPTIONS
LOAD COMPONENTS
PARAMETERS
COST
PARAMETERS
SYSTEM
ENERGY
& HUMIDITY
ENERGY
SIMULATED
BIN
POWER
POTENTIAL
FANTEMPERATURE
BIN
ZONE
OPTIMIZED
FLOW RATE PARAMETERS
EXTERIOR
AIR LOADS
Cold- deck air
Interior load
Cooling coil
Optimized ELECURRENT
BINzone
ENERGY
COST
OPTIMIZED
BIN zone
ENERGY
COST
Transm
relative
HHW
latent
Return
Zone
Total
zone air flow
flow
zone Return
Interior
Optimized
cooling
dollar
Outside
zone air
Total
Whether
- percentage
Interior
Exterior
CHW
load
zone
Interior
percentage
Interior
Cooling/heating
Interior
HHW
zone
Optimized
coil
Exterior
zone
humidity
dollar
load
airPreheat
ELE
HHW
Exterior
Mixed
humidity
Optimized
air
Transmission
zone
CHW percentage
gain
zone
dollar
Interior
Interior
heat
CHW
zonepercentage
Solar
latent
Exterior
coilExterior
zone
load
zone
acrosscoil
ELE
Cooling
Interior
ELErise
Temp.
zone
Exterior
Cooling
Optimized
Exterior
Transmission
Temp. rise across
Lighting andleaving
leaving air humidityTotal heating load Total fan power
flow
temp.
air air
Mixed
Total
load
temp.
flow coil
airair
Preheat
Return
Return
load FANP
power
fan
flow
cooling
Return
Total
power air
Ratio Supply fanOutside
savings
Load
dollar
Partial
ELE
con
savings ratio
humidity
consumption
temperature
ratio
is wetOccupants
savings
coil
temperature
flow ratio
air
temp.
load
supply
savings
entering
reheat
ratio
coil
load
consumption
air flow
temp.
load
latent
leaving
supply
ratio
savings
reheat
component
consumption
ratioconduction
solar
savings
load
temp. savings load
glass
supply
through
temp.savings
supply
flow
load LTEQ
air
load
fan sensible
supply
load
flow
consumption
air
supply fan sensible
sensible
supply return
temperature
equipment
ratio
consumption
Optimized ELE
Optimized CHW
Optimized CHW
Optimized total
Current ELE cost Current CHW cost Current CHW cost Current Total cost
cost
cost(°F)
cost
cost
(B
(°F)
(%)
(Btu/hr)
(kBtu)
(°F) (Btu/hr)
-(°F) (Btu/hr)
($)
(Btu/hr)
(%)
(kBtu)
(Btu/hr)
(lbw/lbda)
($) (°F)
(lbw/lbda)
(°F)
(cfm)
(kWh)(Btu/hr)
(Btu/hr)
(%) (Btu/hr)
(lbw/lbda)
(°F)
(cfm)
(°F) (Btu/hr)
($) (Btu/hr)
(hp)
(kWh)(Btu/hr)
(cfm)
(Btu/hr)
(°F) (Btu/hr)
(%) (Btu/hr)
(hp)
(cfm)
(Btu/hr)
(kWh)
- (Btu/hr)
($)
(cfm)(°F)(Btu/hr)
(°F)
dTSF
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.0
2.1
2.2
2.3
2.4
2.5
2.6
TCL
XR
RH
qFT
Ti QLTEQe
qil
HHW_Opt
XOA Tot_%Sav
qHT
WetCoil
Te QsOCPe
Xi Tot_$Sav
wCL
qiRH
CHW_Opt
qel
Xe HHW_%Sav
wMA
qeRH
VT HHW_$Sav
QTSe
ELE_Opt
wR
qPH
TR
VR CHW_%Sav
TiS CHW_$Sav
qCT
PRF
VOA
QSOLe
qCl
PSF
ViTeSELE_%Sav
qes
QTe
qCs
PLR
VedTRF
ELE_$Sav
($) qis
($) LTEQ_Opt
($) FANP_Opt
($) TMA
($) TPH
($)TCE
($)
($)
0.96
22.4
-23.6
328
38,946
72,583
3,100
72.0
-4
0.04
164,146
72.0
FALSE
340
0.61
4,900
19.9
72.2
37,354
0.011311
3,100
0.39
1
70.3
0
126,792
0.003708
131
70.3
18,280
0
-40.9
72.0
0.003778
17,580
62,565
23
-1
0.0
66.8
6,543
169,775
700
80.0
0
13.8
-47.3
11,080
0.0
108
-61,863
-4
-145,888
0.664
7,200
169,775
ELECost_Cur CHWCost_Cur HHWCost_Cur TotCost_Cur ELECost_Opt CHWCost_Opt HHWCost_Opt TotCost_Opt
0.96
-2.2
26.3
794
72.0
-1
0.04 38,946
72.0
FALSE
954
36.3
72.4
41,825
0.010963
0.39
670.5
0158,734
116,910
0.004378
70.5327
0
-4.6
72.057
0.004448
17,580
68,565
0
0.0
66.3
7,019
190,830
700
77.8 -28.1
02 3,100
13.8
11,080
0.0 0.664
270
-45,176
-7
-129,678
7,200190,830
8
5 3,100
16 18,280
12
3 0.61
4 4,900
20 72,583
3.9
31.8
38,946
5,060
72,583
3,100
72.0
0.04
13
153,323
72.0
FALSE
0.61
4,900
6,992
35.5
72.6
46,295
0.010624
3,100
0.39
70.7
36
0
107,027
0.005311
2,159
70.7
18,280
0
-14.2
72.0
0.005381
17,580
74,565
-8
377
0.0
65.8
7,496
211,884
700
75.7
0
-8.0
13.8
11,080
0.0 0.664
1,782
-28,490
-15
-113,468
7,200211,884
23
9
16
49
30
9
10
50 0.96
6.5
0.96
35.2
38,946
8,283
3,100
72.0
0.04
39
147,911
72.0
FALSE
0.61
4,900
33.8
13,045
72.8
50,766
0.010294
3,100
0.39
70.9
55
0
97,145
0.005876
3,663
70.9
18,280
0
-13.6
72.0
0.005946
17,580
80,565
639
0.0
-15
65.3
7,973
232,939
700
73.5
0
-0.3
13.8
11,080
0.0 0.664
3,024
-11,803
-1
-97,259
7,200232,939
184
59
103
345
199
67
66
332 72,583
4.5 72,583
0.96
36.6
72.0
0.04 38,946
53 4,900
72.0
FALSE
0.61
28.0
27,939
73.015,675
55,236
0.390.009974
8071.0
0142,499
87,263
0.006108
7,196
71.0
18,280
0-81,049
-11.3
72.0
0.006178
17,580
86,565
0.0 3,100
-27
64.8
8,449
1,256
700253,993
71.4 13.8
0 3,100
0.1
11,080
0.0 0.664
4,883
5,940
1
7,200253,993
336
110
164
610
337
125
108
571
3.3
41.3
38,946
72,583
15,354
3,100
72.0
0.04
41
137,087
72.0
FALSE
0.61
4,900
29.0
30,805
73.2
59,707
0.009663
3,100
0.39
71.2
82
0
77,380
0.006910
7,326
71.2
18,280
0
-13.7
72.0
0.006980
17,580
92,565
0.0
-36
64.3
8,926
1,278
275,048
700
69.2
0
-0.9
13.8
11,080
0.0 0.664
21,569
6,048
-6
-64,839
7,200275,048
663
241
285
1,189
662
268
205
1,136 0.96
3.0 72,583
0.96
43.9
38,946
21,463
3,100
72.0
0.04
54
131,675
72.0
FALSE
0.61
4,900
27.1
48,265
73.4
64,178
0.009360
3,100
0.39
71.4
104
0
67,498
0.007348
71.4
10,663
18,280
0
-15.5
72.0
0.007419
17,580
98,565
0.0
-62
63.8
9,403
1,861
296,103
700
67.1
0
1.2
13.8
11,080
0.0 0.664
38,256
8,802
12
-48,629
7,200296,103
668
260
283
1,211
674
296
201
1,171
1.2
49.1
38,946
72,583
24,243
3,100
72.0
0.04
24
126,264
72.0
FALSE
0.61
4,900
23.6
60,894
73.6
68,648
0.009066
3,100
0.39
71.6
98
0
57,615
0.008224
71.6
12,560
18,280
0
-16.5
72.0
0.008294
17,580
104,565
0.0
-83
63.3
9,879
2,192
317,157
700
64.9
0
0.7
13.8
11,080
0.0 0.664
54,942
9
10,368
-32,420
7,200317,157
993
401
385
1,780
981
463
281
1,726 0.96
0.9 72,583
0.96
53.0
38,946
33,043
3,100
72.0
0.04
28
113,942
72.0
TRUE
0.61
4,900
23.1
97,537
73.8
68,931
0.008894
3,100
0.39
71.8
130
0
45,011
0.008951
71.8
18,970
18,280
0
-14.6
72.0
0.008964
17,580
110,565
0.0
-120
62.8
3,310
10,356
336,334
700
62.8
1.0
13.8
5,032
11,080
0.0 0.664
71,629
15,660
18
-16,210
7,200331,302
1,164
502
416
2,082
1,155
585
318
2,058
2.9
53.0
38,946
72,583
32,031
3,100
72.0
0.04
110
91,256
72.0
TRUE
0.61
4,900
33.0
74.0
62,931
121,535
0.008894
3,100
0.39
72.0
206
0
28,325
0.009020
72.0
22,960
18,280
0
-11.1
72.0
0.008964
17,580
116,565
0.0
-117
62.3
4,006
10,832
346,253
700
60.6
0.9
13.8
11,171
0
11,080
0.0 0.664
88,315
18,954
20
7,200335,082
1,763
817
563
3,142
1,745
937
433
3,115 0.96
8.0 72,583
0.96
53.0
40,562
16,188
3,100
72.0
0.04
335
42,378
72.0
TRUE
0.59
4,900
63.7
74.2
42,378
139,677
0.008894
3,100
0.41
0
72.2
372
0.009102
72.2
18,004
25,169
18,673
0
-6.9
72.0
0.008963
17,973
137,118
0.0
-87
60.5
4,541
11,309
365,647
700
57.0
2.1
14.3
18,804
11,080
0.0 0.678
123,006
16,210
20,628
49
7,593346,843
2,132
1,050
626
3,809
2,112
1,167
420
3,699
5.7
53.0
45,057
72,583
13,516
3,100
72.0
0.04
236
36,139
72.0
TRUE
0.56
4,900
63.8
74.5
36,139
148,545
0.008894
3,100
0.44
0
72.4
313
0.009155
72.4
18,444
25,135
19,730
0
-8.1
72.0
0.008959
19,030
143,357
0.0
-107
60.0
4,939
11,786
397,178
700
57.0
1.3
15.9
24,934
11,080
0.0 0.716
140,132
32,420
20,196
30
8,650372,245
2,365
1,255
584
4,204
2,316
1,341
212
3,869 0.96
6.3 72,583
0.97
53.0
49,767
8,671
3,100
72.0
0.03
210
29,901
72.0
TRUE
0.53
4,900
65.8
74.7
29,901
122,998
0.008894
3,100
0.47
0
72.5
219
0.009155
72.5
18,884
19,890
20,787
0
-5.9
72.0
0.008956
20,087
149,595
0.0
-66
59.5
4,230
12,262
424,131
700
57.0
3.0
17.6
26,270
11,080
0.0 0.755
157,258
48,629
15,660
57
9,707397,861
2,343
1,319
490
4,151
2,312
1,426
177
3,916
6.1 72,583
0.97
53.0
6,673
72.0
0.03 54,688
201
23,662
72.0 4,900
TRUE
0.51
69.8
75.0
23,662
126,638
0.490.008894
0 72.6
202
0.009134
72.6
19,323
19,748
21,844
0 64,839
-2.2
72.0
0.008953
21,144
155,834
0.0 3,100
-26
59.0
4,520
12,739
700449,071
57.025,383
1.4 3,100
19.3
11,080
0.0 0.793
174,384
15,228
25
10,764423,688
1,887
1,115
333
3,335
1,830
1,181
114
3,124
8.1
52.9
59,817
2,439
72,583
3,100
72.0
0.03
139
17,424
72.0
TRUE
0.48
4,900
78.2
65,899
75.2
17,424
0.008894
3,100
0.52
0
72.8
115
0.009083
72.8
19,763
10,014
22,902
0
1.5
72.0
0.008950
22,202
162,072
9
0.0
58.5
2,454
13,216
470,705
700
57.0
1.6
21.2
20,983
11,080
0.0 0.831
7,560
191,510
81,049
15
11,822449,723
1,842
1,190
289
3,321
1,817
1,216
87
3,120 0.97
9.8 72,583
0.97
52.9
123
65,150
3,100
72.0
0.03
14
11,185
72.0
TRUE
0.46
4,900
5,423
87.7
75.4
11,185
0.008894
3,100
0.54
0
72.9
12
0.009041
804
72.9
20,203
23,959
0
2.5
72.0
0.008947
23,259
168,311
1
210
0.0
57.9
13,692
492,958
700
57.0
1.5
23.0
16,996
11,080
0.0 0.870
594
208,636
1
97,259
12,879475,962
936
642
147
1,725
921
633
32
1,586
5
8.6
52.9
70,684
72,583
3,100
72.0
1
0.03
4,947
72.0
TRUE
521
0.44
4,900
95.3
4,947
75.6
0.008894
3,100
0.56
0
1
73.0
75
0.009052
73.0
20,642
25,016
0
-5.6
72.0
0.008945
24,316
174,549
21
0
0.0
57.4
14,169
521,499
700
57.0
1.0
25.0
19,097
11,080
54
0.0 0.908
225,762
0
113,468
13,936502,402
75
53
13
142
74
52
2
128 0.97
Space
loads
and
Current
and
optimized
energy
cost
System
parameters
–components
Temperature
System
System
parameters
parameters
–
Fan
–
Air
power
flow
&
rates
humidity
ratios
Optimized
Potential
energy
consumptions
cost
savings
Simulated system consumptionand
loadfractions
7
5
1
13
7
17th Symposium for Improving Building Conditions in Hot and Humid Climates
5
0
12
20
63.7
62.8
61.9
61.0
60.2
59.3
58.4
57.5
57.0
57.0
57.0
57.0
57.0
57.0
57.0
57.0
57.0
Chart Sheet
Plot*
Unit
(a) Energy cost during occupied
Thousand $
(b) Energy cost during unoccupied
Thousand $
(c) Savings during occupied
Thousand $
(d) Savings during unoccupied
Thousand $
(a) Measured and optimized energy use
MMBtu; MWh
(b) System consumption loads and bin hours
MMBtu/hr; hours
(c) Exterior zone loads
MMBtu/hr
(d) Interior zone loads
MMBtu/hr
(a) Temperatures
°F
(b) Air flow rates
Thousand cfm
(c) Humidity ratios and relative humidity
Lbw/lbda
(d) Air flow ratios
%
(a) Measured and optimized energy use
MMBtu; MWh
(b) System consumption loads and bin hours
MMBtu/hr; hours
(c) Exterior zone loads
MMBtu/hr
(d) Interior zone loads
MMBtu/hr
(a) Temperatures
°F
(b) Air flow rates
Thousand cfm
(c) Humidity ratios and relative humidity
Lbw/lbda
(d) Air flow ratios
%
(1) Energy cost and saving
(2) Consumptions and loads during
occupied period
(3) System parameters during
occupied period
(4) Consumptions and loads during
unoccupied period
(5) System parameters during
unoccupied period
*In each chart sheet, (a), (b), (c), (d) refer to the upper left, upper right, lower left and lower right plot.
17th Symposium for Improving Building Conditions in Hot and Humid Climates
21
TotCost_Opt
HHW_Opt
TPH
ELE_Opt
CHWCost_Opt
30
0.5
9
20
8
80
140
25
7
70
120
qClHHWCost_Cur
qCT
Vi
qHT
qFTVOA
HHWCost_Opt
TotCost_Cur
qPH
VR
HOURS
TotCost_Opt
qeRH ELECost_Opt
VT
ELECost_Cur
ELE Consumptions (MWh)
20
5
50
80
4
40
400
0.4
16
7
350
0.4
14
6
300
0.3
12
5
250
flowconsumption
rates
Energy Temperatures
consumptions ←
←→
→ Air
System
load
15
60
3
30
10
40
2
20
5
20
1
10
20
20
20
40
60
80
40
60
80
40
60
80
Bin
Outside
Air
Temperature
(°F)
Bin
Outside
Air
Temperature
(°F)
Bin Outside Air Temperature (°F)
qes
ELE_$Sav
wOA
wR
qel
5.0
0.25
0.016
QTe
CHW_$Sav
wMA
QsOCPe
QSOLe
HHW_$Sav
wCL
QLTEQeRHOA
100
100
100
3
0.2
6
150
2
0.1
4
100
1
0.1
2
50
0
120
120
120
0
0.0
0
00
0
90
5.0
0.25
120%
QTSe
Tot_$Sav
RH
80
70
60
3.0
0.010
0.05
50
20
40
60
80
100
40
120
30
-0.10
0.004
1.0
20
20
20
40
60
40
60
8080
40
60
80
Bin
Outside
Air
Temperature
Bin
Outside
Air
Temperature
(°F)
Bin Outside Air Temperature(°F)
(°F)
qis
ELE_$Sav
Xe
QTSi
qil
Xi CHW_$Sav
QsOCPi XOA
QTi
HHW_$Sav
QLTEQiXR
0
120 120
120
100100
100
QSOLi
Tot_$Sav
PLR
4.5
0.20
100%
4.0
0.15
3.5
0.10
80%
3.0
0.05
2.5
60%
0.00
2.0 0
-0.05
40%
1.5
20
40
60
80
100
120
100
100
120
120
-0.10
1.0
Exterior zone ← Space loads → Interior zone
20
-0.15
0.5
0.002
-0.20
0.0
0.000
0
-0.25 0
200
OCCUPIED PERIOD
Humidity ←
ratios
→ Air →
flow
fractions
Occupied
Cost←savings
Unoccupied
4.5
0.20
0.014
4.0
0.15
0.012
3.5
0.10
2.5
0.008
0.00
2.0 0
0.006
-0.05
1.5
0.3
10
4
0.2
8
OCCUPIED PERIOD
Relative Humidities (%)
00
0
00
0
450
0.5
18
8
Occupied ← Energy costs → Unoccupied
6
60
100
Humidity
Ratios
Exterior
Zone
Loads (lbw/lbda)
(MMBtu/hr)
Savings
during
Occupied
(thousand dollars)
CHWCost_Cur
qCs
qiRHVe
CHWCost_Opt
Hours in Each Bin (Hours)
HHWCost_Opt
CHW_Opt
TMA
FANP_Opt
TCL
ELECost_Opt
Savings
during
Unoccupied
(thousand dollars)
Air
Flow
Ratios
Interior
Zone
Loads
(MMBtu/hr)
CHW & HHW Consumptions (MMBtu)
Temperatures
Energy Cost during
Occupied(°F)
(thousand dollars)
HHWCost_Cur
HHW_Meas
TiS
TR
LTEQ_Opt
Te
Ti
TotCost_Cur
Air during
Flow
Rates
(thousand
cfm)
System
Consumption
Loads
(MMBtu/hr)
Energy
Cost
Unoccupied
(thousand
dollars)
CHWCost_Cur
CHW_Meas
TeS
ELE_Meas
TCE
ELECost_Cur
160
9
90
10
20
20
40
60
80
40
60
80
BinOutside
OutsideAir
AirTemperature
Temperature(°F)
(°F)
Bin
100
100
0
120
120
20%
-0.15
0.5
-0.20
0.0
0%
0
-0.25 0
20
20
17th Symposium for Improving Building Conditions in Hot and Humid Climates
40
60
80
40
60
80
Bin
Bin
Outside
Air
Temperature
(°F)
BinOutside
OutsideAir
AirTemperature
Temperature(°F)
(°F)
22
Example of Application
17th Symposium for Improving Building Conditions in Hot and Humid Climates
24
Sanders Corps of Cadets Center

Introduction
– Single story display hall
(19,363ft2)
– 8:00AM-5:00PM (Mon-Fri)
– One AHU, SDVAV
– CC® implemented by 11/2/2007
– One year Post-CC hourly data of
weather and measured
consumption
17th Symposium for Improving Building Conditions in Hot and Humid Climates
25

Resetting Minimum Airflow
Ext. zone (cfm)
Int. zone (cfm)
Savings
Occupied
7,200 → 3,820
11,080 → 3,600
20%
Unoccupied
6,370 → zero
9,800 → zero
54%
– Reset values are also used in the following optimization
17th Symposium for Improving Building Conditions in Hot and Humid Climates
26
Optimization parameter setting limits
Opt. Parameter
Unit
Lower
Limit
Upper
Limit
Te
°F
70
78
9
Ti
°F
68
72
5
TCL
°F
55
70
16
VOA
cfm
600
4,500
11
Te
°F
65
85
11
Ti
°F
65
85
11
TCL
°F
55
70
16
VOA
cfm
0
4,500
12
Occupied
Unoccupied
17th Symposium for Improving Building Conditions in Hot and Humid Climates
Grid
Division
27
100
Temperatures (°F)
90
Te
Ti
40
60
TCL
80
70
60
50
40
30
0
20
80
100
120
Air Flow Rates (thousand cfm)
Bin Outside Air Temperature (°F)
20
VOA
VT
15
10
5
0
0
20
40
60
80
100
120
Bin Outside Air Temperature (°F)
Optimized parameter settings during occupied period
17th Symposium for Improving Building Conditions in Hot and Humid Climates
28

Potential Energy Cost Savings
Energy cost and savings during
occupied period (thousand $)
– An extra 7% (occupied) and 12% (unoccupied) savings
compared with resetting minimum airflow
25
Baseline Energy Use Cost
Savings from Resetting Vmin
20
Potential Energy Savings
15
10
5
0
ELE
CHW
17th Symposium for Improving Building Conditions in Hot and Humid Climates
HHW
29
Conclusions
17th Symposium for Improving Building Conditions in Hot and Humid Climates
30

Conclusions of Work
– Methodology has been improved and implemented in a
prototype computer tool;
– Using the tool only requires limited information about the
building and the built-in HVAC system, as well as sorted
bin weather and energy consumption data.
– It provides comprehensive output of energy costs and
savings, space loads, and system parameters, etc.
17th Symposium for Improving Building Conditions in Hot and Humid Climates
31
Thanks!
17th Symposium for Improving Building Conditions in Hot and Humid Climates
32