Evaluating the electricity intensity of evolving water supply mixes: the case of California’s water network

Abstract

Climate change is making water supply less predictable, even unreliable, in parts of the world. Urban water providers, especially in already arid areas, will need to diversify their water resources by switching to alternative sources and negotiating trading agreements to create more resilient and interdependent networks. The increasing complexity of these networks will likely require more operational electricity. The ability to document, visualize, and analyze water-energy relationships will be critical to future water planning, especially as data needed to conduct the analyses become increasingly available. We have developed a network model and decision-support tool, WESTNet, to perform these tasks. Herein, WESTNet was used to analyze a model of California's 2010 urban water network as well as the projected system for 2020 and 2030. Results for California's ten hydrologic regions show that the average number of water sources per utility and total electricity consumption for supplying water will increase in spite of decreasing per-capita water consumption. Electricity intensity (kWh m −3 ) will increase in arid regions of the state due to shifts to alternative water sources such as indirect potable water reuse, desalination, and water transfers. In wetter, typically less populated, regions, reduced water demand for electricity-intensive supplies will decrease the electricity intensity of the water supply mix, though total electricity consumption will increase due to urban population growth. The results of this study provide a baseline for comparing current and potential innovations to California's water system. The WESTNet tool can be applied to diverse water systems in any geographic region at a variety of scales to evaluate an array of network-dependent water-energy parameters.

Energy use for urban water management by utilities and households in Los Angeles

“…The current system relies on imported water for a majority of supply from three main sources: the Colorado River Aqueduct (CRA), the California Aqueduct through the State Water Project (SWP), and the Los Angeles Aqueduct to the Owens Valley. While all the sources convey water over significant distances, two of them (CRA and SWP) require significant energy to get water over high elevations into the LA Basin, causing the electricity intensity to exceed that of many other urban areas (Garrison et al 2009, Sanders 2016, Sokolow et al 2016, Sowby and Burian 2017, Stokes-Draut et al 2017, Mika et al 2018 (see Supporting Information).…”

A mass balance approach to urban water analysis using multi‐resolution data

“…Energy in the form of electricity, natural gas, and fuel oil are required to treat and distribute drinking water and wastewater resources (Nair, George, Malano, Arora, & Nawarathna, 2014;Wisniewski, 2015;Chini & Stillwell, 2018;Sowby & Burian, 2017). Embedded energy of urban water systems also contributes to a city's carbon footprint and greenhouse gas emissions (Boulos & Bros, 2010;Alkasseh, Adlan, Abustan, Aziz, & Hanif, 2013;Aubuchon and Roberson, 2014;Nair et al, 2014;Stokes-Draut, Taptich, Kavvada, & Horvath, 2017).…”

Addressing Complex Challenges in Coupled Natural and Human Systems Through Principled Pragmatism: A Case Study From Bangladesh

“…It finds pervasive use in the water literature as an adjective to describe systems that are exceedingly intricate, highdimensional, or difficult to control. In this sense of the word, complexity is a challenge to be overcome through advances in data acquisition (e.g., Chen et al, 2018;Zounemat-Kermani et al, 2018), computational modeling (e.g., Berger et al, 2007;Hadka and Reed, 2015), and technologies that improve the efficiency of resource production, distribution, and consumption (e.g., Fereres et al, 2011;Stokes-Draut et al, 2017). In addition to this colloquial usage, complexity is found in multiple distinct and domain-specific senses within the water literature.…”