Reliability Evaluation of Active Distribution Networks and Wastewater Treatment Plant Electrical Supply Systems

As energy demand increases in U.S. society, especially in terms of electricity and water, it becomes crucial for the operator to ensure the reliability and security of power distribution systems and wastewater treatment facilities. In the past, deterministic approaches were developed in evaluating the reliability of power supply systems. However, deterministic approaches lack the stochastic characteristic modeling, which makes it ineffective in modeling practical systems with increasing uncertainties. In this thesis, a set of probabilistic, quantitative reliability indices will be calculated for the active power distribution networks and wastewater treatment plant (WWTP) electrical supply systems. First, the probabilistic reliability evaluation for active distribution networks is performed. Due to the higher pressure from the environment, the integration of renewable resources and application of storage units has become more prevalent in the past several decades. Consequently, using the conventional deterministic approach to evaluate the reliability of active distribution networks may not be effective anymore. In this thesis, a new method is proposed to evaluate the active distribution system reliability containing microgrid and energy storage. The power output of distributed generator (DG) within the microgrid is first calculated based on the approach of generalized capacity outage tables (GCOTs). Then, the Monte Carlo Simulation (MCS) is utilized for performing power system reliability evaluation. The results obtained considering different energy storage capacities are compared. Furthermore, real-time pricing strategy is incorporated in optimizing the control strategy of the storage device. The reliability indices are then recalculated to inform the system operator in power system planning and operations. Second, the probabilistic reliability evaluation for WWTP electrical supply systems is conducted. Due to the rapid development of industry development and population growth, the electrical power supply system in WWTPs also demands a more comprehensive reliability evaluation, which is currently treated as a mechanical reliability problem in the wastewater treatment industry. In fact, the electrical part also plays an essential role in ensuring the availability and reliability of WWTPs. In this thesis, reliability evaluation mainly focuses on the electrical power supply system instead of the mechanical equipment. Furthermore, the Intelligent Power Motor Control Center (IPMCC) model is incorporated, which is widely used in WWTP control systems. A time-sequential MCS simulation method is used to derive the system reliability indices, and several other techniques are also utilized including the reliability model of IPMCC and the load based reliability indices calculation. A comparison is conducted between the reliability analyses of active distribution system in power systems and the electrical supply system of WWTP. In fact, both systems do have some similarities, such as the component reliability model and the evaluation procedure. However, in terms of some specific characteristics of each system, reliability modeling and evaluation methods may need some changes correspondingly

Demand response within the energy-for-water-nexus - A review. ESRI WP637, October 2019

A promising tool to achieve more flexibility within power systems is demand re-sponse (DR). End-users in many strands of industry have been subject to research up to now regarding the opportunities for implementing DR programmes. One sector that has received little attention from the literature so far, is wastewater treatment. However, case studies indicate that the potential for wastewater treatment plants to provide DR services might be significant. This review presents and categorises recent modelling approaches for industrial demand response as well as for the wastewater treatment plant operation. Furthermore, the main sources of flexibility from wastewater treatment plants are presented: a potential for variable electricity use in aeration, the time-shifting operation of pumps, the exploitation of built-in redundan-cy in the system and flexibility in the sludge processing. Although case studies con-note the potential for DR from individual WWTPs, no study acknowledges the en-dogeneity of energy prices which arises from a large-scale utilisation of DR. There-fore, an integrated energy systems approach is required to quantify system and market effects effectively

Drivers of Microbial Risk for Direct Potable Reuse and de Facto Reuse Treatment Schemes: The Impacts of Source Water Quality and Blending.

Although reclaimed water for potable applications has many potential benefits, it poses concerns for chemical and microbial risks to consumers. We present a quantitative microbial risk assessment (QMRA) Monte Carlo framework to compare a de facto water reuse scenario (treated wastewater-impacted surface water) with four hypothetical Direct Potable Reuse (DPR) scenarios for Norovirus, Cryptosporidium, and Salmonella. Consumer microbial risks of surface source water quality (impacted by 0-100% treated wastewater effluent) were assessed. Additionally, we assessed risks for different blending ratios (0-100% surface water blended into advanced-treated DPR water) when source surface water consisted of 50% wastewater effluent. De facto reuse risks exceeded the yearly 10-4 infections risk benchmark while all modeled DPR risks were significantly lower. Contamination with 1% or more wastewater effluent in the source water, and blending 1% or more wastewater-impacted surface water into the advanced-treated DPR water drove the risk closer to the 10-4 benchmark. We demonstrate that de facto reuse by itself, or as an input into DPR, drives microbial risks more so than the advanced-treated DPR water. When applied using location-specific inputs, this framework can contribute to project design and public awareness campaigns to build legitimacy for DPR

Technology transfer potential of an automated water monitoring system

The nature and characteristics of the potential economic need (markets) for a highly integrated water quality monitoring system were investigated. The technological, institutional and marketing factors that would influence the transfer and adoption of an automated system were studied for application to public and private water supply, public and private wastewater treatment and environmental monitoring of rivers and lakes

Optimizing the Structure and Scale of Urban Water Infrastructure: Integrating Distributed Systems

Large-scale, centralized water infrastructure has provided clean drinking water, wastewater treatment, stormwater management and flood protection for U.S. cities and towns for many decades, protecting public health, safety and environmental quality. To accommodate increasing demands driven by population growth and industrial needs, municipalities and utilities have typically expanded centralized water systems with longer distribution and collection networks. This approach achieves financial and institutional economies of scale and allows for centralized management. It comes with tradeoffs, however, including higher energy demands for longdistance transport; extensive maintenance needs; and disruption of the hydrologic cycle, including the large-scale transfer of freshwater resources to estuarine and saline environments.While smaller-scale distributed water infrastructure has been available for quite some time, it has yet to be widely adopted in urban areas of the United States. However, interest in rethinking how to best meet our water and sanitation needs has been building. Recent technological developments and concerns about sustainability and community resilience have prompted experts to view distributed systems as complementary to centralized infrastructure, and in some situations the preferred alternative.In March 2014, the Johnson Foundation at Wingspread partnered with the Water Environment Federation and the Patel College of Global Sustainability at the University of South Florida to convene a diverse group of experts to examine the potential for distributed water infrastructure systems to be integrated with or substituted for more traditional water infrastructure, with a focus on right-sizing the structure and scale of systems and services to optimize water, energy and sanitation management while achieving long-term sustainability and resilience

Outcome evaluation of research for development work conducted in Ghana and Sri Lanka under the Resource, Recovery and Reuse (RRR) subprogram of the CGIAR Research Program on Water, Land and Ecosystems (WLE).

This is the main report of an external evaluation of the Resource Recovery and Reuse Flagship of the Water Land and Ecosystems (WLE) CGIAR Research Program. WLE commissioned the study. The Evaluators interviewed researchers and partners in two countries, Ghana and Sri Lanka, and in Ghana visited two sites. They also interviewed key international partners and analyzed a wide range of documents, reports and publications. The evaluation was focused on understanding how and in what ways the research and other activities carried out by IWMI and supported by WLE contributed to the outcomes. In essence, the purpose was to understand the specific impact pathways from research to outputs and outcomes

Assessment of the environmental aspects of the DOE phosphoric acid fuel cell program

The likely facets of a nationwide phosphoric acid fuel cell (PAFC) power plant commercial system are described. The beneficial and adverse environmental impacts produced by the system are assessed. Eleven specific system activities are characterized and evaluated. Also included is a review of fuel cell technology and a description of DOE's National Fuel Cell Program. Based on current and reasonably foreseeable PAFC characteristics, no environmental or energy impact factor was identified that would significantly inhibit the commercialization of PAFC power plant technology

NASA JSC water monitor system: City of Houston field demonstration

A water quality monitoring system with on-line and real time operation similar to the function in a spacecraft was investigated. A system with the capability to determine conformance to future high effluent quality standards and to increase the potential for reclamation and reuse of water was designed. Although all system capabilities were not verified in the initial field trial, fully automated operation over a sustained period with only routine manual adjustments was accomplished. Two major points were demonstrated: (1) the water monitor system has great potential in water monitoring and/or process control applications; and (2) the water monitor system represents a vast improvement over conventional (grab sample) water monitoring techniques

Preliminary design study of a baseline MIUS

Results of a conceptual design study to establish a baseline design for a modular integrated utility system (MIUS) are presented. The system concept developed a basis for evaluating possible projects to demonstrate an MIUS. For the baseline study, climate conditions for the Washington, D.C., area were used. The baseline design is for a high density apartment complex of 496 dwelling units with a planned full occupancy of approximately 1200 residents. Environmental considerations and regulations for the MIUS installation are discussed. Detailed cost data for the baseline MIUS are given together with those for design and operating variations under climate conditions typified by Las Vegas, Nevada, Houston, Texas, and Minneapolis, Minnesota. In addition, results of an investigation of size variation effects, for 300 and 1000 unit apartment complexes, are presented. Only conceptual aspects of the design are discussed. Results regarding energy savings and costs are intended only as trend information and for use in relative comparisons. Alternate heating, ventilation, and air conditioning concepts are considered in the appendix