A meta-regression analysis of benchmarking studies on water utilities market structure

This paper updates the literature on water utility benchmarking studies carried out worldwide, focusing on scale and scope economies. Using meta-regression analysis, the study investigates which variables from published studies influence these economies. Our analysis led to several conclusions. The results indicate that there is a higher probability of finding diseconomies of scale and scope in large utilities; however, only the results for scale economies are significant. Diseconomies of scale and scope are more likely to be found in publicly-owned utilities than when the ownership is mostly private; as would be expected, multi-utilities are more likely to have scale and scope economies.economies of scale; economies of scope; meta-regression analysis; water utilities

Current Issues of Water Management

There is an estimated 1.4 billion km3 of water in the world but only approximately three percent (39 million km3) of it is available as fresh water. Moreover, most of this fresh water is found as ice in the arctic regions, deep groundwater or atmospheric water. Since water is the source of life and essential for all life on the planet, the use of this resource is a highly important issue. "Water management" is the general term used to describe all the activities that manage the optimum use of the world's water resources. However, only a few percent of the fresh water available can be subjected to water management. It is still an enormous amount, but what's unique about water is that unlike other resources, it is irreplaceable. This book provides a general overview of various topics within water management from all over the world. The topics range from politics, current models for water resource management of rivers and reservoirs to issues related to agriculture. Water quality problems, the development of water demand and water pricing are also addressed. The collection of contributions from outstanding scientists and experts provides detailed information about different topics and gives a general overview of the current issues in water management. The book covers a wide range of current issues, reflecting on current problems and demonstrating the complexity of water management

Doctor of Philosophy

dissertationPublic water systems face escalating energy requirements due to scarcer water supplies, stricter water quality standards, and population growth. As the challenges of managing finite water and energy resources continue to grow, new data, analyses, and models are needed to help water systems manage their energy use and operate more sustainably. This work offers three original contributions: 1) the discovery of annual, utility-scale energy intensities for public water supply from a panel survey of over 100 U.S. water utilities; 2) an empirical statistical model that accurately predicts a water system's energy use as a function of a few accessible variables and lends itself to fairer energy benchmarking; and 3) the development of a high-resolution method to model energy use within a water distribution network to inform energy management decisions at multiple scales. The survey showed an average water system energy intensity of 1,809 kilowatt-hours per million gallons (kWh/MG) but with substantial spread from 250 kWh/MG to 11,500 kWh/MG and with interannual changes up to 70%. These geographic and temporal variations should be considered in future work. The survey confirmed that a lack of adequate data is one of the greatest barriers to understanding energy-for-water demands. In the statistical model, the most important factors influencing energy use were found to be water system size, water source type, precipitation, and air temperature. By considering such internal and external variables, the model overcomes much of the difficulty in equitable energy benchmarking. The model is more accurate than those developed previously and uses more-accessible variables to estimate energy use, features that are useful when actual observations are unavailable. The technique for modeling energy intensities within a water system, built on extended-period hydraulic modeling, provided specific and actionable energy management insights. A case study with a real water system illuminated energy inefficiencies, and their solutions were validated through actual energy savings. Where water and energy interactions are complex, the method is a valuable analysis tool. Overall, the development of strong datasets, empirical relationships, and modeling techniques helps advance sustainable water supply from an energy perspective, with value to both researchers and practitioners

Murdoch University science and computing building energy simulation & mechanical engineering green building design

Anchored in teaching, research and community engagement approaches, Murdoch University is setting up the development of a symbolic new mixed use campus precinct expansion which is listed as one of Murdoch University’s strategic plan. As stated above, a part of the strategic plan includes the development of a new Mechanical Engineering Building (MEB) in order to engage future Mechanical Engineering students. This newly proposed MEB would be designed and constructed as an extension building from the existing Science and Computing Building that is located at the Murdoch South Street campus. Hence, the major focus of this research study investigate the new Murdoch University Mechanical Engineering green building structure and design by analysing the energy consumption of the existing Science and Computing building. The annual energy consumption of the existing building is obtained through the identification of construction materials, building design and building operational activities. All this information is then simulated using Virtual Environment by Integrated Environmental Solutions (IES-VE). The outline of this IES-VE modelling tool and implementation procedures is illustrated in Chapter 3 (Methodology) and the simulation results used to identify the major sources of the energy use are included in Chapter 4 (Results). The results showed the massive energy consumption that being used in the current Science and Computing building and the annual energy consumption is broken down into different components that makes up the total energy use.Moreover, the possibilities for building energy consumption reduction are discussed and this is based on the low embodied energy building materials and low existing building operational energy reduction strategies. For the sake of achieving green star building standard, NABERS self rating tools are introduced by determining the building operational routines and its design structure. The existing building’s NABERS score will be recognised as a useful measure for the new MEB design ideas and the selection of appliances used in order to achieve the low energy building objectives. Furthermore, the structure and design of the new MEB are drafted based on the essential requirements using SketchUp drawing tool. The dimensions and working purpose of each individual floor are illustrated and reviewed. On the other hand, basic specifications of the MEB such as experimentation and research laboratory requirements, computer appliances and HVAC demands are determined in order to diagnose the NABERS rating and thus establish a new target for green building achievement. The estimated new building energy consumption is generated and possible strategies which include energy efficiency design, energy efficient technologies and renewable technologies are discussed in Chapter 5. Generally, a green building is achieved through an integration of energy efficient programs and environmentally friendly construction projects. Thus, an introduction of potential sustainable strategies is illustrated in Chapter 6 in order to develop Murdoch University into a carbon-neutral community. The potential sustainable strategies that are discussed in this thesis project included rainwater harvesting technology, wastewater treatment plants, timber prefabricated construction and green roof garden implementation. Lastly, project summary is included in Chapter 6 (Conclusion) and several recommendations are discussed that would be important to be evaluated and discussed for further improvement

Estimating the potential water reuse based on fuzzy reasoning

Studies worldwide suggest that the risk of water shortage in regions affected by climate change is growing. Decision support tools can help governments to identify future water supply problems in order to plan mitigation measures. Treated wastewater is considered a suitable alternative water resource and it is used for non-potable applications in many dry regions around the world. This work describes a decision support system (DSS) that was developed to identify current water reuse potential and the variables that determine the reclamation level. The DSS uses fuzzy inference system (FIS) as a tool and multi-criteria decision making is the conceptual approach behind the DSS. It was observed that water reuse level seems to be related to environmental factors such as drought, water exploitation index, water use, population density and the wastewater treatment rate, among others. A dataset was built to analyze these features through water reuse potential with a FIS that considered 155 regions and 183 cities. Despite some inexact fit between the classification and simulation data for agricultural and urban water reuse potential it was found that the FIS was suitable to identify the water reuse trend. Information on the water reuse potential is important because it issues a warning about future water supply needs based on climate change scenarios, which helps to support decision making with a view to tackling water shortage.Foundation for Science and Technology (FCT) under PhD grant SFRH/BD/66277/200

Probabilistic design and upgrade of wastewater treatment plants in the EU Water Framework directive context

The EU Water Framework Directive requires compliance with effluent and receiving water quality standards. This increased complexity implies that the evaluation of the impact of measures should be evaluated with adequate tools, both from the methodological point of view – by applying systems analysis investigations and modelling uncertainty assessment tools – and by making the developed methodology applicable in practice. Urban wastewater systems (UWWSs) are crucial components of river basins, since they usually contribute significantly to the pollution loads. They also have more flexibility in operation and management than other subsystems as agriculture. One part of this dissertation tries to answer the question “where” to improve the UWWS in a basin by means of systems analysis. A case study is tackled with the help of substance flow analysis (SFA) and of performance indicators. SFA allowed to identify the pressures on the receiving water. The indicators highlighted the critical structures in the basin. The spatial scale of the study was found to be of paramount importance. The other part of this dissertation deals with the question “how” to improve the UWWS, by proposing a systematic methodology to design correction measures, illustrated by the example of WWTP design and upgrade. The first step is the generation of influent time series to be fed to the WWTP models by means of a new phenomenological model of the draining catchment and sewer system. Ten different treatment process configurations were selected for the comparison. Further, eleven upgrade options were selected for evaluation, partly requiring real-time control (RTC) and partly the construction of additional treatment volume. For the immission-based evaluation, the integration of the WWTP model with a river model was made by means of the continuity-based interfacing method (CBIM). The propagation of the uncertainty on model parameters was performed with Monte Carlo simulations. Given the assumed boundary conditions, alternating systems show the best treatment cost-efficiency. RTC upgrades showed good potential for low-cost compliance, but with higher risk of limits exceedance. The immission-based evaluation revealed that considering the system from a holistic point of view can lead to substantial savings