Water Usage Patterns Research Articles

Temporal case study of household behavioural response to Cape Town's “Day Zero” using smart meter data

Faced with the threat of “Day Zero”, when it was feared that Cape Town's taps could run dry, consumers reduced household water usage from 540 to 280 L per household per day over the 36 months between January 2015 and January 2018. This paper describes the events that prompted this reduction. We look at how changes in water use were affected by official announcements and by public engagement with this news via the social media activity and internet searches. We analysed the water usage of a subset of middle to high income households where smart hot and cold water meters were installed. For hot water usage patterns we compared meter readings with that in another area unaffected by the drought. We further map our cold water smart meter readings against that of the City of Cape Town's municipal data for domestic freestanding households — a sample of more than 400,000 households. We found that the introduction of Level 5 restrictions had a perverse effect on consumption, possibly due to confusing messages. The most dramatic change in behaviour appears to have been instigated by a media storm and consequent user panic after the release of the City's Critical Water Shortages Disaster Plan in October 2017. However, contradictory communication from national and provincial government eroded some of this gain. The paper concludes with recommendations for demand management in a similar future scenario.

Comfort, peak load and energy: Centralised control of water heaters for demand-driven prioritisation

Recent advances in smart grid technology enable new approaches to address the problem of load control for domestic water heating. Since water heaters store energy, they are well-suited to load management. However, existing approaches have focused on the electrical supply side, ignoring the obvious link between the user and the grid: individual hot water consumption patterns. This paper proposes a load spreading approach in which water heaters compete for access to the heating medium. The proposed smart grid solution takes grid load limits, real-time temperature measurements, water usage patterns, individual user comfort, and heater meta-data into consideration. The scheduler only turns on the heaters with the highest level of need, but limits the number of on heaters to ensure that the grid load stays below a set limit for a set time. The method is evaluated by simulation against various heater set temperature levels, and for various load limits, and compared with ripple control and actual consumption measured in a field trial of 34 water heaters. The proposed algorithm reduces the load from 62 kW to 20, 30, 40, and 50 kW (vs. 106 kW for full ripple control). The resulting number of unwanted cold events is fewer than for ripple control, and only slightly more than no control, while reducing the total energy by 14% from a user-optimised natural experiment.

Sustainability of rainwater catchment systems for small island communities

Communities living on atolls and similar low-lying islands in the tropical Pacific rely on rainwater and shallow groundwater to meet domestic water needs. Rainwater, generally captured and stored using rooftop rainwater catchment systems, is the preferred water source due to higher quality and convenience of access. This study assesses the performance of rainwater catchment systems (RWCS) on Ifalik Atoll, located in Yap State, Federated States of Micronesia in the western Pacific. A field survey was conducted in August 2015 to evaluate RWCS features (guttered roof area, storage tank size, gutter leakage conditions), determine numbers of users, and estimate daily water use via household surveys. All 152 RWCS were surveyed. Water balance modeling was applied to the RWCS to estimate end-of-day stored rainwater volumes for each day of the 1997–1999 time period, during which an El Niño-induced drought occurred. Results indicate that the community is resilient to drought, although the majority of RWCS were depleted of rainwater and hence community sharing was required. Scenario testing indicates that increasing guttered roof area is the optimal strategy for enhancing system reliability. For example, the volume of water maintained at the peak of a drought can be tripled if the available roof areas for the RWCS are guttered. Design curves, which provide a set of roof area – tank volume combinations that achieve specified levels of reliability, were created and can be used to plan new RWCS. Besides offering insights into community-wide water storage and usage patterns and resiliency for Ifalik Atoll, this study presents methods that can be applied to other atoll island communities throughout the Indo-Pacific region.

A minimal simulation of the electricity demand of a domestic hot water cylinder for smart control

In many countries domestic electric hot water storage cylinders have high penetration and account for a large proportion of electricity demand. Their ability to store energy makes them a significant opportunity for emerging smart home energy management systems. One approach to evaluating the potential of hot water cylinders under smart control is to simulate electricity demand via a physical model of a cylinder together with assumed hot water usage patterns. Determining the accuracy of these simulations is made difficult by the lack of detailed data on cylinder variables and household hot water usage. This results in simulation methods that potentially miss essential features or are overly complex. To address this issue, we first propose a statistical fidelity measure that can be used to compare simulated with monitored electricity demand time series from an individual cylinder. We then present a minimal simulation method that achieves reasonable fidelity with monitored demand. The proposed method is particularly useful for simulating individual households using only electricity time-series data for the purpose of evaluating smart home management scenarios.

Analysis of the Spatial Characteristics of the Water Usage Patterns Based on ESDA-GIS: An Example of Hubei Province, China

The spatial characteristics and the high-duty water regions of the Water Usage Patterns (WUP) are very important for the allocation and management of water resources. Taken Hubei province, China as an example, we adopted the exploratory spatial data analysis (ESDA) method to investigate the spatial dependence and local patterns of the WUP from 2003 to 2012. Subsequently, the spatial variation mechanisms were analyzed through the gravity center model. The results indicated that the overall spatial dependence of the agricultural WUP was detected (more significant after 2008). Moreover, the global spatial autocorrelation analysis results on the domestic WUP showed statistical significance (Moran’s I > 0.1, P < 0.05). These indicated that the local patterns were presented. The high values clustering areas of the agricultural and domestic WUP were mainly distributed in the central province and in the western province respectively. However, the approximate random distribution was identified for the industrial WUP because the industrial development had been conducted widely in the whole province during these years. Furthermore, the governmental policies and natural environment contributed to the spatial evolution tendency of the WUP. An increasing trend of the spatial association of the agricultural WUP and a significant decreasing trend of that of the domestic WUP, which suggested that the natural circumstance superiority and the industrial structure adjustment related to water utilization has been utilized and implemented effectively. This study can provide a useful reference and guidance for scientific planning of water resource systems.

Availability Study of Groundwater in Jaffna Peninsula of Northern Sri Lanka

The Jaffna Peninsula lie in the northern-most part of Sri Lanka. It is separated from the mainland by two external lagoons. The Jaffna Peninsula depends for its water on the rainfall which percolates and stored in lime stone aquifers. The average annual rainfall is 1284 mm/year and the potential vapour transpiration is 1858.8 mm. The Jaffna Peninsula is struggling to meet the water demand and quality of available ground water also threatened by pollutants. The major aquifers within Jaffna Peninsula located in Valikamam, Vadamaradchchi and Thenmaradchchi area. From 1966 several surveys and investigations were carried out to find out the water usage pattern, required water and available water, etc. The studies which are carried out in different periods on deriving possible “Safe Yield” from the aquifers of Jaffna Peninsula are showing inconsistent results for the same aquifers. In last few decades the ground water is exposed for the pollution due to over extraction for irrigation lead for sea water intrusion, heavy usage of agro chemicals lead to increase the Nitrate concentration beyond the limit and discharging industrial waste in to ground lead to the contamination of petroleum components.The studies done so far on estimating the availability of groundwater in Jaffna Peninsula have been carried out to certain extent and derived recommendations for “Safe Yield” as well. But the findings are varying with the time period for a specific aquifer. Also the carrying capacity of the aquifers are not clearly studied in detail as the groundwater in Jaffna Peninsula is stored in fractured weak limestone aquifers. Therefore the over storage of groundwater in the aquifers beyond their capacity may cause adverse impact to the environment.Based on the past studies, the recommended total “Safe Yield” from the aquifers in Jaffna Peninsula is 13,100 m3 per day in dry season and 34,600 m3 per day in wet season while having a basic water requirement for domestic need of 31,500 m3 per day. Further available annual water resources is 718 m3 per day per person which is less than the recommended amount in the World Water Development Report of the United Nations. These are indicating that the Jaffna Peninsula is facing the water scarcity.The availability of groundwater and the possible additional recharge shall be studied with correlation to the carrying capacity of the aquifer to ensure and improve the available water resources in a sustainable manner. This paper is analysed and summarised the past studies on groundwater in Jaffna Peninsula.

Characterizing cooling water source and usage patterns across US thermoelectric power plants: a comprehensive assessment of self-reported cooling water data

This study characterizes cooling water sources (by type and quality) and cooling water usage rates in thermoelectric power plants across the US based on data reported by power plant operators to the Energy Information Administration (EIA) for the year 2014. Geospatial distributions of water usage by specific cooling technologies and water sources confirm trends towards wet recirculating cooling systems, dry cooling and reclaimed water usage in the power sector, especially in more water constrained locations. Results include a database of water withdrawal and water consumption rates for 672 unique power plants organized by fuel, prime mover and cooling system classification, expanding available data records by an order of magnitude from previous analyses. While median calculated rates are generally comparable to values reported in the literature for most cooling technologies, results suggest that water usage rates at power plants with unique locations or operating conditions might not be accurately characterized by averages, especially in the case of once-through cooled facilities. Despite previous criticisms of EIA cooling water data, improvements in form instructions, reporting methods, and cooling system definitions have markedly improved the quality and usability of cooling water data records in recent years.

“DAM ALERTS” M-POWERING FARMERS WITH IRRIGATION INFORMATION AND FLOOD ALERTS

Background/Objectives: In spite of major achievements in irrigation sector, there is still no dependable alert and dam information system regarding the level of water in dams, weather condition, water quality and early warning flood alerts in the neighbourhood dams and canals. In this paper the authors describes the development of an innovative and low cost dam information and allied water discharge alert system where the backend data updating and information retrieval from the portal is done using the simplicity and ubiquity offered by mobile phones. Methods/Statistical Analysis: A consultative approach was adopted in gathering the details of the dams, like capacity, alert threshold levels etc. from concerned divisions of the water resource department. The system is implemented using three tier architecture and the SMS based services are offered by integrating web services based API which extends the internet services to the mobile platform. Findings: Information can be requested using a mobile on an anytime anywhere basis and the requested information can be received using an ordinary mobile phone thus bridging the digital divide. This system will enable the not so tech savvy farmers also to access water levels in dams without being physically present at the dam site to read the water level display boards and without the need of a computer with Internet facility. Applications/Improvements: The value add this system brings in over the current manual paper register based system is that the data pooled digitally can be churned to derive valuable insights about the water usage pattern, demand-supply gap, seasonal surges and spikes etc thereby ensuring better management of scarce water resources. This system can be enhanced by deploying sensor nodes which enables more and more parameters to be recorded resulting in more accurate prediction capabilities.

The performance of an evacuated tube solar hot water system in a domestic house throughout a year in a northern maritime climate (Dublin)

The performance of an evacuated tube solar hot water system, installed on a domestic house (occupied by 2 adults and 3 children) in Dublin, Ireland has been intensely monitored over the period of a year. Instrumentation to measure flows and temperature were installed throughout both the solar circuit and domestic hot water system, in addition to solar radiometers being installed on site to measure both global and diffuse radiation. The overall annual solar system efficiency at the installation angle of 29° to the horizontal was 63%. Heat losses from all aspects of the solar circuit and hot water system have also been quantified. The ongoing hot water usage pattern of the house occupants over the course of the year has been analysed as well as the changing attitudes to the use of hot water since the installation of the new solar system. This has shown some evidence that more hot water tends to be used on days where there has been more direct sunlight. Net present value calculations based on 5years of operation however, have shown that the retrofit of such a system is not currently economically viable, although it has produced a carbon saving of approximately 1.1tonnes CO2eq over its first 5years of operation.

An integrated approach to modelling end-use energy and water consumption of Australian households

To predict both end-use energy and water consumption of households, an integrated approach was developed by adding water module into the AusZEH design tool, which was a physically-based model to simulate energy consumption of residential buildings considering building envelop, appliance characteristics, local climate and occupant behaviour. Water and its associated energy consumption includes indoor and outdoor water systems considering actual operation of the water systems. Monte Carlo approach was applied to simulate both energy and water use patterns of appliances considering uncertainties. The comparisons between simulation and actual data show the model can track both energy and water consumption and usage patterns.

Optimization of photovoltaic–thermal (PVT) based cogeneration system through water replenishment profile

A photovoltaic thermal (PVT) system is a renewable cogeneration system that produces low temperature heat and electricity simultaneously from solar radiation. In water based PVT systems, as the thermal load is served, storage tank is replenished immediately with cold makeup water. However, it is possible to determine an optimal water replenishment profile to optimize the overall configuration of PVT system. In this paper, effects of water replenishment on PVT system sizing are studied. At first, the problem is modeled as a mixed integer non-linear programming problem to analyze the impact of water replenishment on PVT system sizing. Subsequently, the design space approach is used to analyze the significance of water replenishment strategy on the PVT system configuration. Finally, based on analytical derivation, an approximate water replenishment profile is determined and its practical implementation strategies are discussed. Applicability of the proposed methodologies is demonstrated through sizing PVT systems for residential as well as industrial hot water usage patterns. Significant reductions in both collector area (10% for residential example and 7% for industrial example) and storage volume (66% for residential example and 23% for industrial example) are observed.

Water Usage Pattern on Different Group Residing in Vicinity Harapan Rainforest

Abstract This study was aimed to investigate water usage behavior on different group who residing in vicinity Harapan Rainforest. The qualitative and quantitative information was collected from 101 respondents by using semi-structure questionnaires. Respondent consist of three groups of people who residing in vicinity rainforest; indigenous people (Suku Anak Dalam), local people (Malay) and migrant (Javanese, Batak and Sundanese). Data was analyzed by using SPSS to describe the distribution pattern of different group on water usage (drinking and sanitary). Data was revealed, the average drinking water is 2.8 L/d/person, cooking sanitation and other is 21.7 L/d/person and total water consumption is 24.5L/d/person. Most of indigenous people were more dependent on river compare to other groups. Meanwhile, local people were dependent on using well as their sources of drinking water. Furthermore, migrant group is mostly dependent on well and commercial drinking water. In conclusion, during drought season local groups prefer to use well compare to others. Most of the households prioritized drinking water from the well in the drought season, where river were only used as sanitary purposes.

Water systems, sanitation, and public health risks in remote communities: Inuit resident perspectives from the Canadian Arctic

Safe drinking water and wastewater sanitation are universally recognized as critical components of public health. It is well documented that a lack of access to these basic services results in millions of preventable deaths each year among vulnerable populations. Water and wastewater technologies and management practices are frequently tailored to local environmental conditions. Also important, but often overlooked in water management planning, are the social, cultural and economic contexts in which services are provided. The purpose of this qualitative case study was to identify and understand residents' perceptions of the functionality of current water and wastewater sanitation systems in one vulnerable context, that of a remote Arctic Aboriginal community (Coral Harbour, Nunavut), and to identify potential future water related health risks. Semi-structured interviews were conducted with 28 Inuit residents and 9 key informants in 2011 and 2012. Findings indicate that the population's rapid transition from a semi-nomadic hunting and gathering lifestyle to permanent settlements with municipally provided utilities is influencing present-day water usage patterns, public health perceptions, and the level of priority decision-makers place on water and wastewater management issues. Simultaneously environmental, social and cultural conditions conducive to increased human exposure to waterborne health risks were also found to exist and may be increasing in the settlements. While water and wastewater system design decisions are often based on best practices proven suitable in similar environmental conditions, this study reinforces the argument for inclusion of social, cultural, and economic variables in such decisions, particularly in remote and economically challenged contexts in Canada or elsewhere around the world. The results also indicate that the addition of qualitative data about water and wastewater systems users' behaviours to technical knowledge of systems and operations can enhance the understanding of human–water interactions and be valuable in risk assessments and intervention development.

계획 신도시 물 사용량 및 이용 패턴 추정

계획 신도시 물 사용량 및 이용 패턴 추정

Fluoride contamination in the Bongo District of Ghana, West Africa: geogenic contamination and cultural complexities

This research investigated the extent of fluoride contamination in the Bongo District of northeast Ghana and the relationships of this fluoride contamination to the underlying geology and precipitation patterns, social and cultural attitudes towards water, and age divisions inherent in water usage patterns and the consequent demands placed on a borehole. The fluoride concentrations measured in the area are higher than reported in earlier literature. High fluoride levels are geographically confined to one geologic formation and appear to be inversely correlated to regional precipitation. Fluoride variation studies, tracking concentrations over 8 months, also reflect this link to local precipitation patterns. This localized analysis of water contamination issues addresses broader gender and policy issues inherent in supplying potable water.

SEASONAL VARIATION IN GREYWATER QUALITY FOR A REAL LIFE SYSTEM

Greywater is a wastewater generated in a house except toilet and kitchen wastewater. It is grossly contaminated but reuse and recycling is possible in water scarcity areas but greywater couldn’t use for drinking purpose. To know the quality of greywater in various seasons specific parameters have to be checked i.e. pH, Acidity, Alkalinity, Hardness, Conductivity, Turbidity, BOD and COD according to “Standard Methods for determining water and wastewater quality, 2000”. Greywater generation from a house contributes 59 % from bath, basin and shower, and 41 % from laundry wastewater. Characteristics of greywater changes due to the number, age, lifestyle, health status and water usage pattern of occupants. In this paper, seasonal variation in quality of greywater will be shown. Here, greywater is mainly used for toilet flushing and gardening purpose. Greywater should be colorless, odorless and should not be acidic. So to get idea of greywater quality, continuous evaluation and proper maintenance is required.

Schistosomiasis transmission; socio-demographic, knowledge and practices as transmission risk factors in pregnant women.

Schistosoma transmission is influenced by the interplay between various factors ranging from parasite to host associated factors. While many studies have focused on mass chemotherapy to reduce transmission in other populations, no study has examined the impact of social factors that favour transmission in pregnant women in Nigeria. The study was conducted to assess the impact of knowledge, attitudes and sociodemographic factors on schistosomiasis burden in pregnant women of rural communities of Nigeria. A cross sectional community-based field study was conducted to assess the association between Schistosoma haematobium burden and the associated risk factors among pregnant women in rural endemic communities of Nigeria. Structured questionnaire was used to gather information on participants' socio-demographic data, knowledge on schistosomiasis and water contact activities. Of the 237 respondents examined microscopically for infection, 50 (21.1%) were infected with overall mean infection intensity of 69.6±165.2eggs/10mL urine. Multivariate logistic analysis showed occupation of the women to be associated with infection with the artisans having the highest risk (OR 3.34, CI 1.67-6.69, P=0.022). Contact with water and water usage patterns are also associated with prevalence of disease with fetching (OR 2.04, CI 0.19-3.51, P=0.003) and multipurpose water usage (OR 4.31, CI 2.17-8.57, P=0.0002) being the most predisposing variables respectively. Awareness about water borne diseases showed no association with infection (P=0.382) with typhoid (23.7%) and fever (2.6%) constituting the most and least common water borne diseases mentioned by the women. Health education and provision of good water supply should be integrated into the control strategies in order reduce transmission in endemic areas.

Water Conservation and Sustainability: An Utmost Importance

Water Conservation and Sustainability: An Utmost Importance

Toward hydro-social modeling: Merging human variables and the social sciences with climate-glacier runoff models (Santa River, Peru)

Original abstract: Glacier shrinkage caused by climate change is likely to trigger diminished and less consistent stream flow in glacier-fed watersheds worldwide. To understand, model, and adapt to these climate-glacier-water changes, it is vital to integrate the analysis of both water availability (the domain of hydrologists) and water use (the focus for social scientists). Drawn from a case study of the Santa River watershed below Peru’s glaciated Cordillera Blanca mountain range, this paper provides a holistic hydro-social framework that identifies five major human variables critical to hydrological modeling because these forces have profoundly influenced water use over the last 60 years: (1) political agendas and economic development; (2) governance: laws and institutions; (3) technology and engineering; (4) land and resource use; and (5) societal responses. Notable shifts in Santa River water use—including major expansions in hydroelectricity generation, large-scale irrigation projects, and other land and resource-use practices—did not necessarily stem from changing glacier runoff or hydrologic shifts, but rather from these human variables. Ultimately, then, water usage is not predictable based on water availability alone. Glacier runoff conforms to certain expected trends predicted by models of progressively reduced glacier storage. However, societal forces establish the legal, economic, political, cultural, and social drivers that actually shape water usage patterns via human modification of watershed dynamics. This hydro-social framework has widespread implications for hydrological modeling in glaciated watersheds from the Andes and Alps to the Himalaya and Tien Shan, as well as for the development of climate change adaptation plans.

The Theoretical Modelling and Optimization of a 10 KWP Photovoltaic Thermal System for a Student Hostel in Singapore

Current commercial photovoltaic (PV) conversion efficiency (flat plate modules) is about 6--20%, depending on the materials used for the module construction. Since only a small fraction (<10%) of the incident solar energy is reflected and/or transmitted, a large fraction of the solar radiation is converted into heat. If this heat can be harvested as well, the overall energy efficiency of such an integrated photovoltaic thermal (PVT) hybrid system will be greatly improved. At the same time, pumping water through the PV modules will cool (if Twater < Tmodule) the solar cells and improve their electricity production efficiency. This article describes the design and numerical simulation of a PVT system for producing electricity and hot water in a student hostel in Singapore. The nominal electrical power output is 10 kWp (kilowatt peak). Thermal models were developed based on basic energy balance equations and average climatic conditions for Singapore over a typical year were used. A survey of the hot water usage pattern over a typical week was carried out and used in the simulation. The optimum mass flow rate in the collectors is found to be 0.039 kg/(s m2) and the optimum storage tank capacity for hot water is 2500 kg for a showering load of around 6000 kg/day. The average thermal and electrical efficiency of the system are 43% and 12%, respectively. The requirement of auxiliary electric energy for water heating is predicted to be reduced by 94%.