世帯人数に基づく室内水消費の汎用数学モデル：サウジアラビアへの適用と水不足地域への転用可能性

Unofficial AI-generated summary based on the public title and abstract. Not an official translation.

🔬研究者:世帯規模と一人あたり水消費の関係を定量化する活動ベースモデルの構築手法が参考になる。

🏢実務担当者:節水器具導入による水・CO2削減の規模感を自社の水リスク評価や設備投資判断に活用できる。

🏛政策担当者:水需要計画に世帯規模分布を組み込むことの政策的意義と節水機器普及策の根拠を提供する。

Water scarcity and stress require urgent improvements in household water usage worldwide, including Saudi Arabia. This study develops an activity and fixture-based mathematical model to estimate daily indoor household water use as a function of household size. Outdoor water use, like for gardens, is excluded because it depends on the type of home and other factors. The model accounts for personal water-use activities such as showering, brushing and flushing etc. and household-level activities covering laundry, dishwashing, miscellaneous kitchen use etc. Also, each activity frequency and time is used to reflect realistic household behavior of Saudi Arabian residents. The mathematical model is implemented in Saudi Arabian context but can easily be used by other countries as per their regional contexts by changing the local data for activities, fixtures, and household type. Per-capita water consumption is calculated for household sizes ranging from 1 to \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:{10}^{+}$$\end{document} members under two scenarios (current and water-efficient fixtures). Results show that per-capita consumption decreases as household size increases, with single-member households using the most water (431.5 L/day) and \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\:{10}^{+}$$\end{document} member households the least (329.4 L/day). Upgrading to efficient fixtures reduces consumption by 27.5% to 28.9% across all household sizes. Scaled countrywide results show that Saudi households would save 1.977 million m³/day and non-Saudi households 1.085 million m³/day (offering an average reduction of 28.0% across both segments). Moreover, 1,117.6 million m³ of water will be conserved annually countrywide by both segments using efficient fixtures, offsetting also approximately 3.70 million tonnes of CO₂ emissions each year. Further analysis reveals distinct consumption patterns as water use is concentrated in medium-sized Saudi households (4–8 members) and (1–3 member) non-Saudi households. Validation and sensitivity analyses confirm that these findings are robust to uncertainties and behavioral offsets, with substantial co-benefits for water and climate. The study highlights the importance of integrating household-size distribution into water-demand planning and demonstrates that water-efficient fixtures offer co-benefits for both water security (SDG-6) and climate action (SDG-13). Develops a scalable activity- and fixture-based model for estimating indoorhousehold water consumption as a function of household size. Demonstrates an inverse relationship between household size and per capita wateruse across Saudi Arabian households. Proposes a design methodology for double-layer primary support rooted in sensitivity analysis of DLPS hardening features and soft rock's rheological property parameters. Quantifies water savings of 27–29% through adoption of water-efficient fixturesunder realistic usage scenarios. Estimates national-scale savings exceeding 3 million m³/day and significantreductions in CO₂ emissions. Provides a transferable framework for water demand planning in water-scarceregions, supporting SDG-6 and SDG-13. Develops a scalable activity- and fixture-based model for estimating indoorhousehold water consumption as a function of household size. Demonstrates an inverse relationship between household size and per capita wateruse across Saudi Arabian households. Proposes a design methodology for double-layer primary support rooted in sensitivity analysis of DLPS hardening features and soft rock's rheological property parameters. Quantifies water savings of 27–29% through adoption of water-efficient fixturesunder realistic usage scenarios. Estimates national-scale savings exceeding 3 million m³/day and significantreductions in CO₂ emissions. Provides a transferable framework for water demand planning in water-scarceregions, supporting SDG-6 and SDG-13.

• semanticscholar https://doi.org/10.1007/s13201-026-03003-9first seen 2026-11-04 05:54:24 · last seen 2026-11-06 05:52:12