Copyright © AWWA 2010 Distribution System Energy Management and Operations Optimization System Implementation at Gwinnett County Brian M. Skeens, P.E.

Acknowledgements Neal Spivey, Gwinnett County Angela Dotson, Gwinnett County Derceto

Need for Real Time Energy Optimization 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

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, 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 hours) every 1/2-hour, adapting to changing conditions of the day Energy Management and Operations (EM&O) Optimization System

takes max advantage of off peak rates Energy Load Shifting

5 MW Reduction Peak kW Reduction

Target the Highest Efficiency Pumps

Chooses Efficient Pump Combinations

Pump Efficiency Improvements

Typical Real Time Optimization Project Overview Phase 1 – Feasibility Study:3 months Phase 2 – Detailed Design:4 months Phase 3 – Implementation8 months SW Configuration /FAT (6 months) Field Installation/SAT (2 months) Phase 4 – Ongoing Support and Maintenance

Derceto AQUADAPT Utility Case Studies Energy Management Installations 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$370k13%800 Eastern Municipal Water District, Perris CA, Stage 1 (2006) 0.6 M$125k10%300 Eastern Municipal Water District, Perris CA, Stage 2 (2007) 0.6 M$150k15%TBA Washington Suburban Sanitary Commission, Laurel MD (2006) 1.7 M$775k11%4,500 WaterOne, Kansas City KS (2006) 0.4 M$800k20%4,800 Region of Peel, ON (2009)* 1.1 M~1M+*16%TBA Gwinnett County, GA (2009)* 0.4 M~$460k*10%TBA * Estimated savings on recent Installations

Gwinnett County, Georgia 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 Gwinnetts 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

Real-Time Market Prices

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

Raw Pumping – Summer Alt 2

Lanier FP Flow & CW Storage – Summer

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

Example Calibrated Pump Curve

VFD Pump Curve Recalibration

Efficiency Improvements Analysis

EM&O DETAILED DESIGN - Savings Review Original projected ROI of 32 months Projected energy cost increase 32% since study Annual Energy BillSavings Type $ Savings% Savings $4.6 MLoad Shifting$ 235K5.1% Efficiency Gains$ 160K4.0% TOTAL$ 395K9.1% Annual Energy BillSavings Type $ Savings% Savings $6.072 MLoad Shifting$ 300K3.5% Efficiency Gains$ 160K4.0% TOTAL$ 460K7.5%

2009 Implementation Key elements of implementation phase; 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 PC on LAN Application Manager 218 PC on LAN Dashboard 210 OPC Current day / real-time Data Cleaner 206 SCADA Interface 203 PC on LAN Operator Panel 201 Operations Simulator 209 Hydraulic Model 208 Primary Database (Live Server) Backup Database

GCDWR Operator Panel – Lanier Central High Service Pumps

2009 Implementation Deliverables Fully configured, tested and implemented energy management and operations optimization system Fully trained operations team (certification contact hours) Fully documented implementation project and user guides

Overall Outcomes Aquadapt software has basically run the Gwinnett County 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