cp2005 scott r1 - vacom technologies · microsoft powerpoint - cp2005_scott_r1.ppt author: doug...
TRANSCRIPT
On Balance:Heat Rejection Controla Packaged Solution
Echelon Americas Channel Partner ConferenceMarch 11, 2005
Presented by
Doug ScottVaCom TechnologiesLa Verne, California
2
Opportunity
An integrated packaged control with:Broad applicabilityValue to end usersValue to integratorsOpen systems benefits
3
Description
One-box integration of:Variable speed drivesBypass controlsControllerUser interfaceEnergy efficiencyCommunications
4
Application
Any type of heat rejection to ambient:Air-cooled condensersEvaporative-cooled condensersFluid coolers (evap or air-cooled)Cooling towers
5
Value to Owners
Lower installed costLower operating costsReliabilityServiceabilityEasier life-cycle cost maintenance
6
Value to Integrators
Higher delivered value to ownerDifferentiation with life cycle cost
Save cost and time vs. custom buildNew business
Retrofit previous projectsFirst opportunity for new customersLeverage utility incentives
7
Add to Open Systems Value
Subsystem control example:Integrate subsystem elementsBuilt-in energy efficiency optimizationPush intelligence closer to end-use
Information = service opportunityManufacturers monitor during warrantyThird party service and monitoring
Flexibility: integrate now or later
8
Energy Background
Concepts Vapor compression cycleLift and floating head pressureVariable speed – affinity lawsSystem balance
9
Vapor Compression Cycle
CompressorPower
Compressor
Low-pressure
Vapor
Evaporator
Condenser
Low-pressureLiquid
LiquidHigh-pressure
Expansion Valve
Low-pressureVapor
Heat source (Cooling)
BASIC CONCEPTS
Energy is conserved -- energy in equals energy out.
Compressor pumps vapor; refrigerant has the cooling effect: Lb/Hr X BTU/Lb= BTU/Hr
High-pressure Vapor
10
Cooling System “Lift”
Evap
orat
or /
Con
dens
ing
Tem
p
-20
100
70
20Lo
w T
empe
ratu
reFi
xed
Hea
d
Low
Tem
pera
ture
Floa
ting
Hea
d Med
ium
Tem
pFi
xed
Hea
d
Med
ium
Tem
pFl
oatin
g H
ead
Fixed
Floating
11
Fixed vs. Floating Head Pressure
20
30
40
50
60
70
80
90
100
Jan Feb Mar Apr May Jun Jly Aug Sep Oct Nov Dec
Tem
pera
ture
, F
Ambient Fixed Setpoint Floating Setpoint
12
Variable Setpoint Control
40
50
60
70
80
90
100
Ambient Temperature Condensing Temperature Setpoint
13
Floating Head Pressure –Impact on capacity
30
40
50
60
70
80
90
5060708090100
Condensing Temperature, F
Capacity, Tons
14
Floating Head Pressure –Impact on capacity and power
30
40
50
60
70
80
90
5060708090100
Condensing Temperature, F
Capacity, Tons Power, kW
15
Floating Head Pressure –Net effect on efficiency
0
0.2
0.4
0.6
0.8
1
1.2
5060708090100
Condensing Temperature, F
Efficiency, kW/Ton
16
Variable Speed Fan Control Third power relationship
0 %
1 0 %
2 0 %
3 0 %
4 0 %
5 0 %
6 0 %
7 0 %
8 0 %
9 0 %
1 0 0 %
0 % 1 0 % 2 0 % 3 0 % 4 0 % 5 0 % 6 0 % 7 0 % 8 0 % 9 0 % 1 0 0 %
F an S p eed %
Fan
Pow
er %
Capacity varies directly with change in
airflow
Fan power varies with
cube of change in airflow
80% speed = 51% power
50% speed = 12% power
17
Part Load PerformanceVariable speed vs. fan cycling
50% capacity 50% power
80 BTUH/Watt
50% capacity 12% power
330 BTUH/Watt
On On Off Off
50% 50% 50% 50%
Specific efficiency increased by 300% with variable speed
18
Energy SavingsEnergy Savings come from:
Lower head pressureLower fan power
Variable speedVariable setpoint
System stabilityOverall: optimum system balance
19
Early ExperienceSuccessful supermarket trial
Vons Controls Retrofit -- Four Store Summary
0
200
400
600
800
1000
1200
1400
Jan Feb Mar Apr May Jun Jly Aug Sep Oct Nov Dec
Mon
thly
kW
h, T
hous
ands
1995 kWh
Cumulative Savings
92 - 94 Average kWh
Savings Target
20
Case Study
Cold storage warehouse in StocktonEvaporative condenserBase case = fixed SCT at 85 FOptions
Float SCT using fixed setpointAdd variable setpointAdd variable speed with fixed setpointAdd variable speed with variable setpoint
21
Results
FHP FSP VSP VFD Savings Payback NPV
X X 6,400$ 0.3 63,500$
Control Options
Annual Energy, mWh
0 250 500 750 1000
Base
Option 1
Compressor Condenser
22
Results
FHP FSP VSP VFD Savings Payback NPV
X X 6,400$ 0.3 63,500$
X X 8,400$ 0.6 80,300$
Control Options
Annual Energy, mWh
0 250 500 750 1000
Base
Option 1
Option 2
Compressor Condenser
23
Results
FHP FSP VSP VFD Savings Payback NPV
X X 6,400$ 0.3 63,500$
X X 8,400$ 0.6 80,300$
X X X 9,100$ 4.4 52,900$
Control Options
Annual Energy, mWh
0 250 500 750 1000
Base
Option 1
Option 2
Option 3
Compressor Condenser
24
Results
FHP FSP VSP VFD Savings Payback NPV
X X 6,400$ 0.3 63,500$
X X 8,400$ 0.6 80,300$
X X X 9,100$ 4.4 52,900$
X X X 21,600$ 2.1 175,300$
Control Options
Annual Energy, mWh
0 250 500 750 1000
Base
Option 1
Option 2
Option 3
Option 4
Compressor Condenser
25
Example System
75 Ton condenser for two glycol chillers with four
separate high sides
Estimated first cost savings:
$3,000 savings in reduced custom programming
$2,500 savings in reduced on-site electrical installation cost and MCC hardware
26
Typical Panel
27
Controller I/O
Analog inputsAmbient DBTAmbient RHDischarge pressures
Digital inputsFan enablesVFD statusOverride statusPump proofDefrost monitor
Digital outputsVFD enableVFD auto bypassPump enableEmergency spray
Analog outputsVFD speed
28
Controller Functions
CapabilityUp to four separate pressures or temperature inputsTwo VFDs per controller
VFD controlAuto, bypass and service modesAutomatic restartsAutomatic bypass
Control logicFixed setpoint Variable setpoint using DBT or WBTPID controlSCT calculation for different refrigerants
Other featuresEmergency spray controlRun time and cycle monitoring
29
Communications Interface
i.LON100 used for:Initial setupCurrent statusSetpointsAlarms and datalogging
Use web browser for setup, setpoint adjustments and current status
http://63.110.57.69/forms/main.htm
37
Performance Monitoringusing EnergyDashboard™
Remote efficiency monitoringReal time, continuous performance analysisWeb based results presentation
High level performance metrics Energy efficiency: kW/Ton, $/Ton-HrMaintenance indicatorsTrends (e.g. refrig. level, inventory)
