Optimization of Energy and Water Quality Management Systems for Drinking Water Utilities

Transcription

1 No part of this presentation may be copied, reproduced, or otherwise utilized without permission. of Energy and Water Quality Management Systems for Drinking Water Utilities May 21, 2015

2 Acknowledgements Funding Agencies Water Research Foundation California Energy Commission Project Team MWH Global Carla Cherchi, PhD Joan Oppenheimer, BCES Christopher Bros Joseph Jacangelo, PhD Project Managers Linda Reekie (WRF) David Weightman (CEC) Project Advisory Committee Joe Young Jack Jacobs Jeff Daniel Steve Conrad, PhD Derceto, Inc. Matthew Gordon Vessie Pencheva Christophe Jay Iyad Darcazallie

3 Acknowledgements Participating Utilities Austin Water Utility, TX California-American Water Company, CA City of Aurora Utilities, CO City of Houston, TX City of Lake Oswego, OR City of Riverside, CA Colorado Springs Utilities, CO East Bay Municipal Utility District, CA Eastern Municipal Water District, CA El Paso Water Utilities, TX Las Vegas Valley Water District, NV Newport News Waterworks, VA Northumbrian Water Limited, UK North Texas Municipal Water District, TX San Antonio Water System, TX Tarrant Regional Water District, TX United Utilities, UK United Water, NJ

4 Agenda Background Current State of EWQMS Implementation Project Objectives Research Approach Pilot Study Results Cost-Benefit Analysis Implementation Challenges Conclusions

5 Background EWQMS concept provides a framework to minimize energy costs while meeting water quality goals within a utility s daily operational constraints Water utilities engage in a broad array of strategies to minimize energy costs, but traditional EWQMS does not necessarily focus solely on energy efficiency or GHG emissions reduction More than 90% of GHG emitted from a drinking water facility is due to electricity consumption EWQMS integrated with energy/ghg optimization will allow water utilities to identify energy efficient alternatives and more sustainable operations

6 Chronological Development of EWQMS

7 EWQMS Framework An EWQMS is a system control management tool that cohesively addresses energy management and water quality within operational constraints Adapted from Jentgen et al., 2003

8 EWQMS Framework An EWQMS is a system control management tool that cohesively addresses energy management and water quality within operational constraints Adapted from Jentgen et al., 2003

9 Head (m) Efficiency (%) 80 EWQMS Principle Pump Curve Efficiency Curve Can exceed 40% of monthly costs Flow (m 3 /h) Energy Efficiency CONSTRAINTS OBJECTIVE FUNCTION Water Quality Demand Charges Energy Charges OFF PEAK MID PEAK ON PEAK MID PEAK Energy Charges Energy Cost Reduction System Hydraulic Equilibrium FLAT TARIFF TOU Permits and Regulations Asset Management

10 Agenda Background Current State of EWQMS Implementation Project Objectives Research Approach Pilot Study Results Cost-Benefit Analysis Implementation Challenges Conclusions

11 Selected EWQMS Implementations Utility Name Utility Location Peak Flow (MGD) % of Entire system Pump stations Eastern Municipal Water District (EMWD) California, US % 59 East Bay Municipal Utility District (EBMUD) California, US % 16 El Paso Water Utilities (EPWU) Texas, US % 54 Northumbrian Water Limited (NWL) UK % 64 Las Vegas Valley Water District (LVVWD) Nevada, US % 52

12 Infrastructure Needed for EWQMS Utility Software Hydraulic Model SCADA Short-term Demand Forecasting EMWD Aquadapt InfoWater, Innovyze OASyS, Schneider Electric Derceto EBMUD Aquadapt InfoWater, Innovyze OASyS, Schneider Electric Derceto EPWU Aquadapt H 2 Omap, Innovyze RSVIEW32, Rockwell Derceto NWL Aquadapt Piccolo, Safege SERCK, Schneider Electric Derceto LVVWD In-house H2OMap, Innovyze OASyS, Schneider Electric In-house

13 Energy Cost Savings Achieved through EWQMS Utility Operational Energy Costs ($/year) Energy Cost Savings Achieved ($/year) (%) Energy Consumption (MWh/year) Energy Savings (%) EMWD 1.7M 377K 22% 12,825 8% EBMUD 2.8M 360K 12.5% 26,127 13% EPWU 6.7M 500K - 800K* 7.5%* 66,980 6% NWL 8.5M (Essex) 11M (Northeast) 586K ~800K 8% 67,605 87,509 N/A LVVWD 13M 3M 23% 1377 kwh/mg 6% *Predicted

14 Project Cost and Payback Software Period license of EWQMS Implementation Configuration Personnel training Utility Project Cost ($) Estimated Payback Period (years) EMWD $1.87M 5 EBMUD $0.75M N/A EPWU $1.30M 3 NWL $3.75M 2-3 LVVWD N/A N/A

15 Agenda Background Current State of EWQMS Implementation Project Objectives Research Approach Pilot Study Results Cost-Benefit Analysis Implementation Challenges Conclusions

16 Research Questions Energy Source Energy Efficiency Energy Charges CONSTRAINTS OBJECTIVE FUNCTION Energy Energy GHG Cost Consumption Reduction Reduction Water Quality System Hydraulic Equilibrium Permits and Regulations Asset Management

17 Energy Efficiency Energy Charges Permits and Regulations Research Questions Energy Source CONSTRAINTS OBJECTIVE FUNCTION Cost/Energy/GHG Reduction Asset Management Water Quality System Hydraulic Equilibrium How does the EWQMS work if GHG reduction is a driver? What happens to water quality if the EWQMS operation is based on the lowest GHG operation? Does lower GHG operation result in increased operating cost for water utilities?

18 Agenda Background Current State of EWQMS Implementation Project Objectives Research Approach Pilot Study Results Cost-Benefit Analysis Implementation Challenges Conclusions

19 Research Approach Modify EWQMS with a GHG module Phase I Phase II Conduct offline simulations of the pilot sites Real-Time operation of the modified EWQMS Phase III

20 Conceptual Framework INPUT Pump/Efficiency Curves Demand Forecaster Tariff Rates/ GHG Emission Factors Historical Calculations Historical Data HYDRAULIC MODEL (e.g., pump flows, pump head, tank levels, tank outflows) System Constraints (e.g., water quality, tank min/max levels, hydraulic equilibrium) Optimizer Initial Schedule (pumping schedule, pump combination, tank levels, cost and kwh use predictions) NO EPANET Control Schedule hydraulically feasible and acceptable water quality? OUTPUT YES Final Schedules and Predictions

21 Offline Tool OFFLINE OPTIMIZATION TOOL: Version 1.0

22 Goals Pump operated when the cost is minimum Pump operated at the lowest specific energy (kwh/mg) Cost Pump operated at the lowest specific energy (kwh/mg) Assumes flat tariff operations kwh Pump operated when the GHG emission factor is minimum Pump operated at the lowest specific energy (kwh/mg) GHG System under manual control by operators Baseline

23 Agenda Background Current State of EWQMS Implementation Project Objectives Research Approach Pilot Study Results Cost-Benefit Analysis Implementation Challenges Conclusions

24 Pilot Sites Selection Eastern Municipal Water District, CA East Bay Municipal Utility District, CA Pilot Area Selection Criteria Configuration: Operations in a closed system Ability to maintain full pump control Availability of mixed energy supplies consisting of natural gas and grid electricity (only at EMWD) Ability to utilize a mixture of flat rate and TOU tariff Low operational and financial risk to the utility The tool has the capability to include gas pumps

25 EMWD Pilot Site PILOT SITE Diamond 3 Searl Tank Mission 1 Tank Mission 2 Tank Mission Canyon MG 0.1 MG 0.1 MG Mission Canyon 2

26 EMWD Electric Tariffs OFF PEAK MID PEAK ON PEAK MID PEAK TOU FLAT TARIFF TOU

27 27,348 30,138 30,897 31,645 32,630 33,472 34,537 35,420 36,328 37,757 38,978 39,727 41,472 42,289 43,488 44,361 45,154 46,306 47,259 48,519 50,473 51,960 53,512 55,158 CO2 (Lbs) GHG Principle Energy Source Energy Efficiency CONSTRAINTS OBJECTIVE FUNCTION Water Quality 600 Electrical Load (MWh) PLEXOS MODEL Energy Charges Energy Energy GHG Cost Consumption Reduction Reduction System Hydraulic Equilibrium Permits and Regulations Asset Management

28 TOU Emission Factor Profile

29 Gas vs. Electricity Driven Pumping Year 2010 Year 2013 Gas Electric Gas Electric Flow MG Energy Consumption kwh/mg GHG Emissions Cost lbs/kwh lbs/mg cents/kwh $/MG

30 Percentage of pumping (%) EMWD Real-Time Operation Results Mission Canyon 2 Off-Peak Mid-Peak Peak 100% 80% 60% 40% 20% 0% Baseline (Electric) Cost kwh GHG

31 Energy (kwh) Total Cost ($) EMWD Real-Time Operation Results 1, Demand Charges Energy Charges Baseline Cost kwh GHG 5,900 5,800 5,700 5,600 Baseline Cost kwh GHG

32 EMWD Offline vs. Real-Time Comparison Scenario Cost (% reduction) Offline Simulations Pilot Energy (% reduction) Offline Simulations Pilot GHG (% reduction) Offline Simulations Pilot Cost kwh GHG -3.4% 7.8% 1.7% 2.9% 1.7% 2.9% % -5.6% 2.8% 2.9% 2.8% 2.9% -9.5% 1.7% 2.7% 2.9% 2.7% 2.9%

33 EBMUD Pilot Site PILOT SITE Blackhawk 1 Blackhawk 2 Scenic 3.0 MG PUMPING STATION Blackhawk 4.5 MG 4.5 MG PUMPING STATION Acorn Acorn Scenic East PUMPING STATION Blackhawk East 1.2 MG 4.0 MG

34 EBMUD Electric Tariffs OFF PEAK MID PEAK ON PEAK MID PEAK

35 Percentage of pumping (%) Percentage of pumping (%) 100% 80% 60% 40% 20% EBMUD Offline Simulation Results Blackhawk Off Peak Mid Peak Peak 0% Baseline Cost kwh GHG 100% 80% 60% 40% 20% Acorn Off Peak Mid Peak Peak 0% Baseline Cost kwh GHG

36 Percentage of pumping (%) Percentage of pumping (%) Percentage of pumping (%) EBMUD Real-Time Operation Results 100% Blackhawk Off Peak Mid Peak Peak 80% 60% 40% 20% 100% Acorn Off Peak Mid Peak Peak 0% Baseline Cost kwh GHG 80% 60% Blackhawk East Off Peak Mid Peak Peak 40% 100% 20% 80% 60% 0% Baseline Cost kwh GHG 40% 20% 0% Baseline Cost kwh GHG

37 Energy (kwh) EBMUD Real-Time Operation Results 42,000 40,000 38,000 36,000 Baseline Cost kwh GHG

38 EBMUD Offline vs. Real-Time Comparison Scenario Cost (% reduction) Offline Simulations Pilot Energy (% reduction) Offline Simulations Pilot GHG (% reduction) Offline Simulations Pilot Cost kwh GHG 25.3% 23.7% -0.4% 4.8% -0.4% 4.8% -22.3% 21.8% 6.1% 5.3% 6.1% 5.3% -0.9% 17.8% 3.3% 4.8% 3.3% 4.8%

39 Energy (kwh) EBMUD Most Efficient Pump Selection Objective Identification of the highest priority pumps Operation Pump 1 in manual operation at all pumping stations Pump 2 in manual operation at all pumping stations Pump 3 in manual operation at all pumping stations Operation with the highest priority pumps Operation under EWMQS System manually operated with the pump duty set in the most efficient priority order System operated under EWQMS optimized for cost 27,000 26,000 25,000 24,000 23,000 22,000 Manual Pump Operation Under Rotation Policy Manual Operation Using Most Efficient Pumps EWQMS Operation Using Most Efficient Pumps

40 EBMUD Simulated Water Age Baseline Cost kwh GHG Baseline Cost kwh GHG Acorn Tank Blackhawk #1 and #2 Tanks

41 Total Chlorine (mgcl 2 /L) EBMUD Chlorine Residual in Tanks Baseline Cost kwh GHG

42 Agenda Background Current State of EWQMS Implementation Project Objectives Research Approach Pilot Study Results Cost-Benefit Analysis Implementation Challenges Conclusions

43 Tangible Cost-Benefits Costs (-) Benefits (+) Capital Investments Infrastructure (SCADA, Meters, Telemetry) EWQMS Software Software Design and Installation Operational Expenses Licensing Fees Maintenance Labor Energy Cost Savings Cost Cost Savings Savings Incentives through DR Programs Revenue kwh Reduction GHG Emissions Reduction Environmental Benefits Operator Training Refresher Training

44 Intangible Cost-Benefits Costs (-) Benefits (+) Capital Investments Risks Cultural Conflicts Water Age Concerns Risk Associated w/ Implementation Improved Maintenance Planning Improved Emergency Response Improved Asset Performance Visibility Increased Customer Goodwill Improved Strategic Simulations/ Planning Cost Avoidance Improved Water Quality Improved Uniformity of Operations

45 Agenda Background Current State of EWQMS Implementation Project Objectives Research Approach Pilot Study Results Cost-Benefit Analysis Implementation Challenges Conclusions

46 Challenges and Recommended Practices Constraints Overrides Cultural Issues Training

47 Challenges and Recommended Practices Constraints Overrides Initially set the system with the lowest number of constraints possible Identify conflicts in order to rank and prioritize constraints based on their level of importance Cultural Issues Training

48 Challenges and Recommended Practices Constraints Overrides Reducing the number of constraints, improving field resolution and maintenance, and initiating training programs for operators Perform a lessons learned to identify root causes and recommended improvements in software, training, constraints/rules Cultural Issues Training

49 Challenges and Recommended Practices Constraints Overrides Cultural Issues Organize meetings among the IT, operation, and management departments to discuss integration issues Involve the operators at all stages of the project to better understand issues and provide useful inputs Management and engineers should consider alternative perspectives of different occupational groups Training

50 Challenges and Recommended Practices Constraints Overrides Cultural Issues Training Multiple operator training sessions, using the simulator, should be offered during the installation phase Recommended Trainings: HMI operator training and initial Pre-FAT operator training On-site training/verification during installation Follow-up training

51 Conclusions Cost optimization not only saved energy costs but also reduced energy consumption and consequently GHG emissions substantially EWQMS can be implemented for kwh/ghg optimization; however, any trade-offs between cost reduction and least GHG/kWh operation should be carefully examined Water utilities should just focus on kwh optimization to achieve the lowest GHG operation until the variability of GHG emission factors are well established Commitments from all levels of the organization are critical for a successful implementation of EWQMS

52 Thank You Comments or questions, please contact: Download report at: For more information visit: