Sensitivity of Optimal Tradeoffs between Cost and Greenhouse Gas Emissions for Water Distribution Systems to Electricity Tariff and Generation

Abstract

Increased awareness of climate change has shifted the focus of water distribution system (WDS) optimization research from cost minimization only to the incorporation of energy or associated greenhouse gas (GHG) minimization. In this study, a sensitivity analysis is conducted to investigate the impact of electricity tariff and generation (emission factors) on the results of multiobjective WDS optimization accounting for both total economic based optimization approach is used to conduct the analysis. The results show that electricity tariff has a significant impact on the total economic cost of WDSs and the selection of optimal solutions. In contrast, the changes of emission factor into the future have a significant impact on the total GHGs from WDSs. However, it does not alter the final solutions on the Pareto-optimal front.

Lost in Optimisation of Water Distribution Systems? A Literature Review of System Design

“…A multi-objective optimisation approach was possibly first applied in the late 1990s (Figure 1), maximising the network benefit on one hand and minimising the system cost (of network rehabilitation) on the other hand [63]. In studies of newly designed WDSs, in addition to the economic measure, the other objectives considered were the pressure deficit [30,62,[64][65][66][67] or excess [68,69] at network nodes, the penalty cost for violating the pressure constraint [70], greenhouse gas (GHG) emissions [71][72][73][74][75][76] or emission cost [77], water discolouration risk [68] and water quality [78]. A multiobjective optimisation approach is considered "very appealing for engineers as it provides a tool to investigate interesting trade-offs", for example, a marginal pressure deficit can be outweighed by a considerable cost reduction [67].…”

Comparison of Pumping Regimes for Water Distribution Systems to Minimize Cost and Greenhouse Gases

“…Objectives of pumping electricity cost and GHG emissions are considered separately and the characteristics of the optimal operating strategies for the objectives are compared. Multi-objective optimization of cost and GHG emissions for WDSs has been extensively covered in Wu et al (2010a); Wu et al (2010b); Wu et al (2011); Stokes et al (2012b); Stokes et al (2012c); Wu et al (2012a); Wu et al (2012b); Wu et al, (2013);and Stokes et al (2014). This research is different in that it considers the effect of the different pump operating regimes on each objective individually.…”

PEPSO: Reducing Electricity Usage and Associated Pollution Emissions of Water Pumps

“…Wu et al included the effect of variable emission rates and electricity tariffs in their WDS design optimization study [14]. Stokes et al also suggested a framework for the modeling and optimization of Greenhouse Gases (GHG) emissions associated with energy usage and pump operation [15].…”