Operations Optimization: Maximize Water Quality and Supply – Minimize Cost

Water utilities are facing significant challenges. From limited funds to aging infrastructure and multiplying security concerns, current drivers require utility managers to be more resourceful than ever. As high-quality water supplies decline, water quality regulations become more stringent, operating costs increase and customer expectations soar, new tools are needed to respond to the complexity.

Operations Optimization is a management tool offering water utilities a fast, efficient, proactive means to minimize cost and maintain a reliable and high quality water supply to their customers, every minute of the day – every day.

Providing Valuable Real-time Data

Operations Optimization provides a comprehensive management solution that includes an accelerated software development cycle, advanced software solution techniques, maximized use of existing SCADA system assets, new business processes, and the empowerment of staff through involvement and training. There are multiple components involved:

• Business processes – redefining how work is accomplished at the utility
• Organization – new, formalized system for planning and scheduling based on new processes being implemented at the utility
• Technology – implementation of reSolveSM, EMA’s advanced system optimization software that meets individual utilities’ operational needs

The reSolve software works in concert with a Supervisory Control and Data Acquisition (SCADA) system to provide valuable data for system analysis, enabling the utility to have constant control of pumps and valves to minimize cost and maximize water quality and supply. The resulting Operating Plan allows the utility to optimize system operations (Figure 1), using a daily planning process, to control the entire water system in the most efficient manner possible.

Systems Approach Considers the Whole Process

A systems approach to optimization takes a planned, comprehensive look at the entire water system, yielding a “systems” view of the key information – from the raw water resource through the entire water “value chain” to the customer (Figure 2). This approach provides effective overall operations management, optimizing energy and minimizing maintenance costs.

The first step in this four-step process (Figure 3) is to understand what opportunities exist for integrated, system-wide optimized control. Step 2 defines and models new operational protocols to support centralized, optimized control of the water system. In Step 3, these business models define requirements, cost, and expected benefits; and Step 4 implements the right custom optimization solution for your utility.

Concept Originated in the Electric Utility Industry

The concept of Operations Optimization is not new. For 40 years, the electric utility industry has used optimization successfully to control generation every few seconds to reduce costs. Electric utilities use Energy Management Systems (EMS) to centrally control power plant output – minimizing transmission line losses and maximizing economies of generation.

EMA, in conjunction with the American Water Works Association Research Foundation (AwwaRF) and the Electric Power Research Institute (EPRI), conducted research over the past 10 years to transfer these electric utility EMS concepts to water utilities. This includes not only the technology, but also the operational discipline and structured protocols. In an electric utility, an entire system can fail in minutes if protocols are violated. This same rigor of operation is a useful model for water utilities, too. For example, it includes a structured clearance process that defines when equipment be removed for maintenance or key values operated in the distribution system.

Working Together to Customize Your Solution

Every utility is different, requiring a solution customized to manage the unique features of your water supply, treatment plants, distribution system, and technology. The first step is an assessment of current operational performance to analyze three important aspects of your utility:

• Process – existing processes, instrumentation and control to identify potential energy management, water quality, and water supply opportunities
• Organization – utility organization structure (staffing, alignment, etc.) and how it will inhibit or enable optimization
• Technology – existing SCADA and plant control systems and instrumentation to support optimization

There are four key components to the EMA solution:

1. Water Consumption Forecaster utilizes neural net technology to forecast daily and annual consumption to 95 percent accuracy
2. Water Supply Analyzer, a rules-based program, evaluates inputs affecting water supply and generates an optimum water supply priority schedule in the form of plant production limits and goals
3. Water System Simulator/Scheduler (Figure 4) with an integrated optimizer and neural network model, evaluates water system performance to develop a daily, optimal production schedule that minimizes energy usage and maximizes use and sustainability of the utility’s existing water resources
4. Water Quality Analyzer evaluates quality information from multiple sources, in real time, to quickly respond to potential problems in the water system

Once the assessment is complete, EMA provides multiple services:

• Workshops to jointly develop operational and business process changes (Figure 5)
• Application design to build various modular components that integrate to solve optimization problems and meet operating strategies and objectives
• Implementation services to program and fully test each module in the optimization solution and monitor on-going business results
• Design and installation of control system changes such as SCADA system upgrades, process automation, and instrumentation upgrades
• Software package review and selection, implementation, and configuration

Return-On-Investment

Utilities implementing Operations Optimization have been pleased with the compressed time frame and the tangible (and relatively quick) Return-On-Investment (ROI). In part, rapid ROI is possible because of the fast-track, four-step, Define-Validate-Deploy-Improve (D-V-D-I) approach being
used (Figure 6).

The four steps are:

• Define best practices and technology
• Validate to confirm these meet the requirements (dynamically simulating conditions using the reSolve optimization suite)
• Deploy into the operation, monitoring results to evaluate performance
• Improve continuously to keep the process operating at peak efficiency

Gensym’s G2 software suite – the world’s leading real-time reasoning technology – is used as the base for rapid deployment of the reSolve system.

Optimization Benefits

Optimization yields substantial improvement in water system operations with savings in a variety of areas (Figure 7).

The following results are typical:

• Reduced energy costs of pumping and maximized hydro generation
• Improved management of multiple water supplies – both ground and surface water
• Reduced cost of water supplies
• Improved coordination of maintenance positively influencing system operations
• Reduced capital costs – need for new investment is reduced by maximizing the efficiency of current systems
• Maintained consistent high quality water through real-time monitoring of water quality parameters