Transcript Slide 1

Distribution System Energy Management and
Operations Optimization System
Implementation at Gwinnett County
Brian M. Skeens, P.E.
Copyright © AWWA 2010
Acknowledgements
≈ Neal Spivey, Gwinnett County
≈ Angela Dotson, Gwinnett County
≈ Derceto
Need for Real Time Energy Optimization
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Rising Energy Costs
– (Second largest cost behind labor)

Manage energy cost in real-time rate environment
– Many systems have option of real-time hourly pricing
– Systems in deregulated markets can negotiate rates and structure

Reduce energy use (and GHG emissions)
– 85% energy use is pumping - manage pumping for best efficiency

Operate more consistently to best utilize & protect assets
– Do not breach system constraints (pressures, etc)
Typical Power Use in a Water System
Other (HVAC,
Lighting), 6% Backwash, 5%
Raw Water Pumps, 31%
High Zone Pumps, 21%
Main Zone Pumps, 37%
89 %+ of Water System Energy Use is in Pumping
Energy Costs Typically 2nd Behind Labor
20 % of all energy used in California is Water Pumping
50 % of all energy use in Dallas, TX is Water Pumping
Range of Solutions
≈ Capital equipment upgrades
≈ Standard operating procedures (SOPs) development
≈ Partial automation (PLC coordination)
≈ Full, real time automation (Energy Management Operations
System)
≈ Understand potential savings and calculate the payback
period for capital costs
Cost Reduction Techniques
≈ Moving Energy (kWh) in Time
(Energy Load Shifting)
≈ Reducing (peak) Demand Charges
(kW)
≈ Generating Efficiency Gains

Selecting most efficient pumps or
combination of pumps
≈ Selection of lowest production
cost sources of water
≈ Selection of lowest cost transport
path for water
Pump
lifecycle costs
Why a Real Time Optimization System?
≈ Interfaces directly to existing SCADA with minimal equipment,
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instrumentation or hardware changes
Operational tool to schedule pumps/valves to achieve lowest overall
cost (without breaching constraints)
Solves mass-balance first (i.e. must deliver water)
Aims to minimize costs of energy (best use of off-peak rates)
Aims to maximize energy efficiency of pumps (BEP)
Can improve water quality by managing turnover
Runs in real time – Like an autopilot
Recalculates schedule (next 24-48 hours) every 1/2-hour, adapting to
changing conditions of the day
Energy Management and Operations (EM&O) Optimization System
Energy Load Shifting
Scenic East Energy Usage Comparison
Peak
Part Peak
100%
90%
80%
Usage
70%
60%
50%
40%
30%
20%
10%
0%
Month
takes max advantage of off peak rates
Off Peak
0
Observed With Derceto
Day
Expected Without Derceto
31-May
30-May
29-May
28-May
27-May
26-May
25-May
24-May
Max Peak-Time kW (May 2006)
23-May
22-May
21-May
20-May
19-May
18-May
17-May
16-May
15-May
14-May
13-May
12-May
11-May
10-May
9-May
8-May
7-May
6-May
5-May
4-May
3-May
2-May
1-May
Sum of kW at WTP and Intakes
Peak kW Reduction
5 MW Reduction
20000
18000
16000
14000
12000
10000
8000
6000
4000
2000
Target the Highest Efficiency Pumps
Chooses Efficient Pump Combinations
80 100 120 140 160 180 200
100
60
30
40
20
20
10
90
80
60
50
40
0
0
2
4
Telemetry Points
Paper Curve (2 pumps)
Scaled Curve (2 pumps)
6
Flowrate (MGD)
8
10
12
Paper Curve (1 pump)
Scaled Curve (1 pump)
Scaled Efficiency Curve (1 pump)
14
Efficiency (%)
70
0
Head (ft)
Combining Pumps
Pump Efficiency Improvements
EBMUD Pump Efficiency Improvements, 2003-2008
18%
11 %
16%
14%
Pre-Aquadapt
Frequency
12%
Post-Aquadapt
Mean Pre-Aquadapt
10%
Mean Post-Aquadapt
8%
6%
4%
2%
0%
0.00%
10.00%
20.00%
30.00%
40.00%
50.00%
Efficiency
60.00%
70.00%
80.00%
90.00%
100.00%
Typical Real Time Optimization Project Overview
≈ Phase 1 – Feasibility Study:
3 months
≈ Phase 2 – Detailed Design:
≈ Phase 3 – Implementation
4 months
8 months
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SW Configuration /FAT (6 months)
Field Installation/SAT (2 months)
≈ Phase 4 – Ongoing Support and Maintenance
Derceto AQUADAPT Utility Case Studies
Total Utility
Population
Served
Annual
Savings
(US$)
Energy Cost Savings
(%)
Annual
CO2 Reduction
(Ton)
East Bay Municipal Utility District,
Oakland CA (2004)
1.3 M
$370k
13%
800
Eastern Municipal Water District,
Perris CA, Stage 1 (2006)
0.6 M
$125k
10%
300
Eastern Municipal Water
District, Perris CA, Stage 2 (2007)
0.6 M
$150k
15%
TBA
Washington Suburban Sanitary
Commission, Laurel MD (2006)
1.7 M
$775k
11%
4,500
WaterOne, Kansas City KS (2006)
0.4 M
$800k
20%
4,800
Region of Peel, ON
(2009)*
1.1 M
~1M+*
16%
TBA
Gwinnett County, GA (2009)*
0.4 M
~$460k*
10%
TBA
Energy Management Installations
* Estimated savings on recent Installations
Gwinnett County, Georgia
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800,000 Population Served
2 Water Filtration Plants, 145 MGD Peak Demand
8 Pressure Zones,19 Storage Tanks, 9 RCVs
17 Pumping Plants with 44 Pumps
$ 4.6 M power cost in 2006
Gwinnett Optimization Drivers
Neal Spivey, Director of Water Production quoted their key operational drivers for pursuing an
optimization project as being:
≈ Operational Consistency
Overall objectives of distribution system operation were met, but
 Each operator had his own preference for an operational scheme
≈ Asset Management
 Required better information on pump efficiency, run hours, lead-lag, so better pump schedule
selection based on “best fit” could be made coincident with Gwinnett’s Asset Management
concept.
≈ Energy Cost and Usage
 Power cost and the economy were both considerations.
 Cost was $4.6 M in 2006 and anticipated $ 6.1 million in 2010
 Energy management and cost reduction were prudent strategies
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Real-Time Market Prices
14.0
12.0
Price (¢/kWh)
10.0
8.0
Jun 07-08
Jun 06
6.0
Oct 07-08
Oct 06
4.0
2.0
0.0
0:00
2:00
4:00
6:00
8:00
10:00
12:00
Time of Day
14:00
16:00
18:00
20:00
22:00
2007 Analysis of Options
≈ Optimization feasibility study completed by CH2M HILL and
Derceto concluded:
 Short Term: Savings estimated at $235k of “Incremental
Energy”
 Long Term: Savings on “Standard Bill”
 Risk Mitigation: Operating on real-time market
 Other Savings: Pump operating efficiency gains
 Other Benefits: Water turnover, predictable operation &
planning
Will Take Advantage of Real-Time Energy Pricing
Raw Pumping – Summer Alt 1
SC to Lanier Raw Water Historical Summer Operation
350
40
35
30
250
25
20
200
150
10
5
100
0
50
-5
Date
Derceto Raw Pumps from SC intake
Historical Raw Pumps from SC intake
Derceto Raw Water Storage
Min/Max Raw Lanier Storage
Day Ahead Price
21/06/2006 12:00
21/06/2006 0:00
20/06/2006 12:00
20/06/2006 0:00
19/06/2006 12:00
19/06/2006 0:00
18/06/2006 12:00
18/06/2006 0:00
17/06/2006 12:00
17/06/2006 0:00
16/06/2006 12:00
16/06/2006 0:00
-10
15/06/2006 12:00
0
15/06/2006 0:00
MGD and $/MWh
15
MG
300
Raw Pumping – Summer Alt 2
SC to Lanier Raw Water Summer Operation
40
350
30
300
25
250
20
15
200
5
150
0
100
-5
-10
50
-15
0
Historical Raw Pumps from SC intake
Date
Derceto Raw Pumps from SC intake
Derceto Raw Water Storage
Min/Max Raw Lanier Storage
Day Ahead Price
21/06/2006 12:00
21/06/2006 0:00
20/06/2006 12:00
20/06/2006 0:00
19/06/2006 12:00
19/06/2006 0:00
18/06/2006 12:00
18/06/2006 0:00
17/06/2006 12:00
17/06/2006 0:00
16/06/2006 12:00
16/06/2006 0:00
15/06/2006 12:00
-20
15/06/2006 0:00
MGD and $/MWh
10
MG
35
Lanier FP Flow & CW Storage – Summer
SC to Lanier Raw Water Historical Summer Operation
350
40
35
30
250
25
20
200
150
10
5
100
0
50
-5
Derceto Lanier FP Flow Rate
Date
Historical Lanier FP Flow Rate
Day Ahead Price
Derceto Lanier CW Storage
Historical Lanier CW Storage
Min/Max CW Storage
21/06/2006 12:00
21/06/2006 0:00
20/06/2006 12:00
20/06/2006 0:00
19/06/2006 12:00
19/06/2006 0:00
18/06/2006 12:00
18/06/2006 0:00
17/06/2006 12:00
17/06/2006 0:00
16/06/2006 12:00
16/06/2006 0:00
-10
15/06/2006 12:00
0
15/06/2006 0:00
MGD and $/MWh
15
MG
300
WFP Flow Rate Change Example
2008 Detailed Design
≈ Gwinnett decided to proceed with an optimization
system design and implementation project
 Based on industry proven software solution (Derceto
Aquadapt)
 Timing driven by budget availability (drought / economy)
≈ Key elements of detailed design phase included:
 Operational workshops and constraints specification
 Hydraulic modeling/analysis and pump curve calibration
 Review of optimization benefits (savings estimate
updated to $400k+) and revised operating strategies
 Energy management software configuration
specification
 SCADA / HMI interface & IT design
 Project WBS, schedule and implementation timelines
Paul West/ATL worked
in NZ with Derceto
during Detailed Design
HAZOP Meeting & Constraints
≈ Hazards and Operability (HAZOP) Workshops
≈ HAZOP Summary
≈ Constraints for each Asset at All Facilities
Reservoir operating levels
 Pressure constraints
 Pump station constraints
 Valve constraints
 WFP constraints
 Other constraints
 Other modes of operation
≈ Fill Valves Recommendations
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Example Calibrated Pump Curve
VFD Pump Curve Recalibration
Efficiency Improvements Analysis
90%
80%
70%
60%
50%
40%
30%
20%
10%
0%
Projected Efficiency Improvements
Estimated Improvement
Average Efficiency
EM&O DETAILED DESIGN - Savings Review
Annual Energy Bill
Savings Type
$ Savings
% Savings
$4.6 M
Load Shifting
$ 235K
5.1%
Efficiency Gains
$ 160K
4.0%
TOTAL
$ 395K
9.1%
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Original projected ROI of 32 months
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Projected energy cost increase 32% since study
Annual Energy Bill
Savings Type
$ Savings
% Savings
$6.072 M
Load Shifting
$ 300K
3.5%
Efficiency Gains
$ 160K
4.0%
TOTAL
$ 460K
7.5%
2009 Implementation
≈ Key elements of implementation phase;
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Aquadapt software configuration
Optimizer server hardware procurement
Integration with calibrated hydraulic model
Transdyn SCADA / HMI interface testing
Transdyn RTU/PLC updated for optimization operating mode
Set-up robust “real-world” test environment
for factory acceptance testing (FAT)
On-site installation and operator training
and site acceptance testing (SAT)
Key Aquadapt Modules
Water Utility
SCADA System
OPC
Operator Panel
201
PC on
LAN
SCADA Interface
203
Current day / real-time
Primary Database
(Live Server)
Data Cleaner
206
Application Manager
218
Hydraulic Model
208
Backup
Database
PC on LAN
Dashboard
210
PC on
LAN
Operations Simulator
209
GCDWR Operator Panel –
Lanier Central High Service Pumps
2009 Implementation
≈ Deliverables
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Fully configured, tested and implemented energy
management and operations optimization system
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Fully trained operations team (certification contact hours)
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Fully documented implementation project and user guides
Overall Outcomes
≈ Aquadapt software has basically run the Gwinnett County
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system since December 2009, with few surprises or difficulties.
Settings have been modified quickly to correct competing
actions (too many pumps for conditions, etc).
Support has been excellent.
Project is a good story to tell (public relations).
Initial evaluation of savings from the first 4 months of 2010
(compared to 2009):
 Total system pumping ~ 11 MGD more
 Energy bills are ~$100,000 lower, so far
 Expecting much more savings as water demand increases
Preliminary Savings Results
Water Pumped
5,000
4,000
MG
3,000
2,000
2009
2010
1,000
0
January
February
March
month
April
Preliminary Savings Results
Power Cost
$400,000
$300,000
2009
2010
$
$200,000
$100,000
$0
January
February
March
month
April
Preliminary Savings Results
Cost per Million Gallons Pumped
$100
$80
$/MG
$60
$40
2009
2010
$20
$0
January
February
March
month
April
Preliminary Savings Results
KWH/MG
Power use per Million Gallons
1400
1200
1000
800
600
400
200
0
2009
2010
January
February
March
month
April
Preliminary Savings Results
Cost per KWH
0.085
0.08
$/KWH
0.075
0.07
0.065
2009
2010
0.06
January
February
March
month
April