The effect of reducing per capita water and energy uses on renewable water resources in the water, food and energy nexus

Abstract

This study assesses the feedbacks between water, food, and energy nexus at the national level with a dynamic-system model, taking into account the qualitative and quantitative environmental water needs. Surface and groundwater resources are considered jointly in the water resources subsystem of this dynamic system. The developed model considers the effects of reducing the per capita use water and energy on its system’s components. Results indicate that due to feedbacks the changes in per capita uses of water and energy have indirect and direct effects. About 40% of the total water savings achieved by the per capita change policy was related to energy savings, in other words, it is an indirect saving. Implementation of per capita use reductions compensates for 9% of the decline of Iran's groundwater reservoirs (non-renewable resources in the short term) that occur during the five-year study period. The Manageable and Exploitable Renewable Water Stress Index (MRWI) corresponding to water and energy savings equals 214.5%, which is better than its value under the current situation (which is equal to 235.1%).

Groundwater for People and the Environment: A Globally Threatened Resource

“…The recharge of treated sewage, stormwater, and diverted surplus streamflow into aquifers for subsequent use by means of managed aquifer recharge constitutes an active effort to achieve sustainable groundwater use by means of managed aquifer recharge (Dillon et al 2019). Other options available to combat groundwater depletion are strategically managing the trade of virtual water (i.e., water consumed in the production of goods, Delpasand et al 2020, 2022), expanding alternative water sources such as seawater desalination powered by renewable energy (see, e.g., Gao et al 2017) and protective of marine ecosystems (Sheibani et al 2023), modifying cropping patterns and dietary customs in favor of foods that have a lower water footprint (Kheirinejad et al 2022; Radmehr et al 2022), metering water use and pricing water at its marginal cost to reduce wasteful use (Kiparksy et al 2018; Maples et al 2018), and developing a shared groundwater platform for groundwater monitoring and prediction (Condon et al 2021).…”

Framing a novel holistic energy subsystem structure for water-energy-food nexus: A review of existing literature

“…Function and aims of the WEF nexus system approach In the WEF nexus approach, actions in the water sector led to changes in energy and food subsystems so that the decision-making pattern will be coordinated in WEF subsystems 27,31 . The WEF nexus is tasked with exploring how three WEF subsystems will grow together and interact with one another 32,33 . Furthermore, synergies and trade-offs will be grown due to their management in the nexus system approach 19,[34][35][36] .…”

Framing a novel holistic energy subsystem structure for water-energy-food nexus based on existing literature (basic concepts)

“…In the WEF nexus approach, actions in the water sector led to changes in energy and food subsystems, so the decision-making pattern will be coordinated in WEF subsystems 28 , 32 . The WEF nexus is tasked with exploring how three WEF subsystems will grow together and interact with one another 33 , 34 . Furthermore, synergies and tradeoffs will be grown due to their management in the nexus system approach 19 , 35 – 37 .…”