Contribution of Adriana Hulsmann in cooperation with Peter van Thienen and Ilse Pieterse-Quirijns (KWR Watercycle Research Institute).
Summary
SIMDEUM® (SIMulation of water Demand and End-Use Model) is the water demand end-use model developed at KWR to predict water demand patterns with a small time scale (1 second) and a small spatial scale (residence level). The end-use model is based on independent statistical information and not on flow measurements. The input parameters are available before any information on annual or daily use is available:
the parameter are not fitted on flow measurements. Therefore, the model is transferable to diverse residential areas in different countries. The model can be applied in the design stage (pre-build), in scenario studies, in water quality distribution network models and to determine leakage losses. The SIMDEUM® model has been applied in the Netherlands and abroad e.g. Hamburg, Germany.
Importance
SIMDEUM® is a new, proven tool that can be helpful in different ways. Firstly, it allows the drinking water installation for a new home, apartment building, hotel or office to be designed more efficiently and sustainably. Secondly, it supports the application and development of water quality models in the drinking water distribution network, to help to keep the water quality at a constant level. The reliable predictions made by SIMDEUM® of water demand in a residential or non-residential building give the designer the opportunity to make a sustainable, hygienic and energy-efficient drinking water installation, without compromising water quality or comfort.
SIMDEUM® can be used to predict water demand for various different types of buildings. This information can also be used to determine leakage losses. This becomes apparent when water consumption during the night period is much higher than predicted by SIMDEUM®.
A detailed understanding of the hydraulics in the drinking water distribution network cannot be gained solely on the basis of measurements. The variations in water demand over time and space are too great to make it possible to carry out sufficient measurements. Instead, what is needed is a reliable water demand model with a small temporal and spatial scale. SIMDEUM® is such a model. It makes a much better estimate of actual hydraulic circumstances possible. By incorporating a good understanding of the specific hydraulics, SIMDEUM® permits a better interpretation of water quality measurements in the distribution network, and better predictions of the water quality in the drinking water distribution network. An improved hydraulics model based on SIMDEUM® demand patterns supports the application and development of water quality models in the drinking water distribution network.
Approach
Our water use is predictable. Most people will use the toilet after they wake up; most take a bath or shower in the morning, or before they go to bed. When do they brush their teeth? Usually, after breakfast and before going to bed. How about doing the dishes? We tend to do them after dinner, or let the dishwasher run at night.
SIMDEUM® combines the predictability of human behaviour with statistics on water use and the technical specifications of water-using appliances. It therefore makes extensive flow measurements at each tap unnecessary. SIMDEUM® simulates water demand over the course of the day on a per-second basis, and is based on information of water use at the fixture level.
Figure 36 – SIMDEUM® SIMulation of water Demand and End-Use Model (KWR).
Census data such as the number of people per household and their ages; the frequency of use; duration and flow per water-use event; occurrence over the day for different end uses such as flushing the toilet, doing the laundry, washing hands etc.
With this approach, residential water demand patterns can be simulated.
Results (or proof)
The Netherlands’ Uneto-VNI has used SIMDEUM® to develop standard design parameters for water installations in new buildings. Drinking water company Oasen in the Netherlands has used SIMDEUM® to study the effect of using a separate hot tap water distribution network. Wageningen University & Research centre (the Netherlands) is employing SIMDEUM® to study the possibility of using alternatives to drinking water, such as grey water and rain water, for toilet flushing.
Implementation
Working together with a consultant, users will be able to identify the appropriate SIMDEUM® input parameters for their particular purposes. These might include specific behavioural components relevant to a certain country or region, or to a specific type of building. In addition, users will be identifying relevant design parameters; for example the maximum instantaneous flow, for sizing pipes, or the maximum hot water use over 10 minutes and 2 hours, for sizing the hot water tank. KWR will run the simulations with SIMDEUM® and extract the design parameters. On this basis the user will be in a position to produce a more sustainable design of the drinking water installation for a particular building in a specific country or region.
References
Blokker, E.J.M., J.H.G. Vreeburg and J.C. van Dijk (2010): Simulating residential water demand with a stochastic end-use model. Journal of Water Resources Planning and Management, 136(1), 19-26.
Blokker, E.J.M., J.H.G. Vreeburg, H. Beverloo, M. Klein Arfmann and J.C. van Dijk (2010): A bottom-up approach of stochastic demand allocation in water quality modelling. Drinking Water Engineering and Science, 3, 43-51.
Blokker, E.J.M., E.J. Pieterse-Quirijns, J.H.G. Vreeburg and J.C. van Dijk (2011):
Simulating Non-residential Water Demand with a Stochastic End-Use Model. Journal of Water Resources Planning and Management, 137(6), 511-520.
Pieterse-Quirijns, E.J., H. Beverloo and W. van der Schee (2011): Validation of design rules for peak demand values and hot water use in non-residential buildings. 38th International Symposium CIB W062 on Water Supply and Drainage for Buildings, Aveiro, Portugal, 86-92.
Pieterse-Quirijns, E.J., C.M. Agudelo-Vera and E.J.M. Blokker (2012): Modelling sustainability in water supply and drainage with SIMDEUM®. 38th International Symposium CIB W062 on Water Supply and Drainage for Buildings, Aveiro, Portugal, 23-36.