B041 Domestic water benchmark

A benchmarking model for water consumption of high-rise residential buildings of Hong Kong

Brief:

Fresh water consumption is one of the primary importance to the design of sustainable water systems in buildings and water consumption benchmarks are developed for the promotion of sustainability. A simple normalization requires precise regional and timing adaptation while a complicated benchmarking model could impose extra adaptation difficulties. In this study a simple benchmarking model for ‘per capita’ domestic water consumption using a five-star rating system with an updating algorithm was proposed. The model was tested with some existing domestic water consumption patterns reported in worldwide as a prior estimate of consumption and the latest regional water consumption survey as a likelihood function for assessing the model validity. The results showed that the posterior average consumption was agreed with the Hong Kong global fresh water consumption patterns. This epistemic approach would be useful for evaluating the benchmarks of water consumption under continuous monitoring. This study also presented a template for formulating epistemic water consumption benchmarks for residential premises elsewhere. It was demonstrated that, with the model, water consumptions for the least sustainable households, i.e. the top 10% of the survey samples in water consumption, which awarded the lowest sustainability rating ‘1 star’, and the most sustainable households (i.e. the bottom 10%) which awarded the highest rating ‘5 stars’. This simple benchmarking model could be useful for identifying the extreme cases of water consumption and promoting the policy on sustainable building designs and operations without inclusive measurements.

Further information:

Wong LT, Mui KW, Hui PS, 2007. A benchmarking model for water consumption of high-rise residential buildings of Hong Kong, The 1^st Hong Kong-Taiwan Workshop on Water Systems in High-rise Buildings, 25 Jun, Hong Kong, pp. 28-35.