An assessment of the energy and water embodied in commercial building construction

Growing global concern regarding the rapid rate at which humans are consuming the earth’s precious natural resources is leading to greater emphasis on more effective means of providing for our current and future needs. Energy and fresh water are the most crucial of these basic human needs. The energy and water required in the operation of buildings is fairly well known. Much less is known about the energy and water embodied in construction materials and products. It has been suggested that embodied energy typically represents 20 times the annual operational energy of current Australian buildings. Studies have suggested that the water embodied in buildings may be just as significant as that of energy. As for embodied energy, these studies have been based on traditional analysis methods, such as process and input-output analysis. These methods have been shown to suffer from errors relating to the availability of data and its reliability. Hybrid methods have been developed in an attempt to provide a more reliable assessment of the embodied energy and water associated with the construction of buildings. This paper evaluates the energy and water resources embodied in a commercial office building using a hybrid analysis method based on input-output data. It was found that the use of this hybrid analysis method increases the reliability and completeness of an embodied energy and water analysis of a typical commercial building by 45% and 64% respectively, over traditional analysis methods. The embodied energy and water associated with building construction is significant and thus represents an area where considerable energy and water savings are possible over the building life-cycle. These findings suggest that current best-practice methods of embodied energy and water analysis are sufficiently accurate for most typical applications, but this is heavily dependent upon data quality and availability.

Modelling direct and indirect water requirements of construction

Water consumed directly by the construction industry is known to be of little importance. However, water consumed in the manufacture of goods and services required by construction may be significant in the context of a building's life cycle water requirements and the national water budget. This paper evaluates the significance of water embodied in the construction of individual buildings. To do this, an input-output-based hybrid embodied water analysis was undertaken on 17 Australian non-residential case studies. It was found that there is a considerable amount of water embodied in construction. The highest value was 20.1 kilolitres (kL)/m2 gross floor area (GFA), representing many times the enclosed volume of the building, and many years worth of operational water. The water required by the main construction process is minimal. However, the water embodied in building materials is considerable. These findings suggest that the selection of elements and materials has a great impact on a building's embodied water. This research allows the construction industry to evaluate design and construction in broad environmental terms to select options that might be cost neutral or possibly cost positive while retaining their environmental integrity. The research suggests policies focused on operational water consumption alone are inadequate.

Domestic drinking water in rural areas : are water tanks on farms a health hazard?

The aim of the research was to gain a better understanding of the relationship between drinking water quality, householders' knowledge and maintenance practices of private water supplies and drinking water-related public health risk on farms. Samples of drinking water were taken from 100 farming households. The Colilert-18 method was used for the detection of total coliforms and Escherichia coli (E. coli) as indicators of water quality. Each household completed a questionnaire about their knowledge and practices relating to a safe water supply. Coliforms were present in 52 water samples and E. coli was present in 38. Seven households reported minor illnesses in the previous three months and two households reported gastroenteritis. Some tank maintenance occurred in 86 households, but tank maintenance activities varied considerably. Four of the households had published guidelines on water quality. None of the participating households had their drinking water tested regularly. There was no obvious relationship between drinking water quality, householder knowledge, maintenance practices and drinking water-related health risk on farms.

Net energy analysis of solar and conventional domestic hot water systems in Melbourne, Australia

It is commonly assumed that solar hot water systems save energy and reduce greenhouse gas emissions. The net energy requirement of solar hot water systems has rarely been analysed, including their embodied energy. The extent to which solar hot water systems save energy compared to conventional systems in Melbourne, Australia, is shown through a comparative net energy analysis. It was shown that the embodied energy component of the net energy requirement of solar and conventional hot water systems was insignificant. The solar hot water systems provided a net energy saving compared to the conventional systems after 0.5–2 years, for electric- and gas-boosted systems respectively.

Net energy analysis of solar and conventional domestic hot water systems in Melbourne, Australia

It is commonly assumed that solar hot water systems save energy and reduce greenhouse gas emissions. Very rarely has the life-cycle energy requirements of solar hot water systems been analysed, including their embodied energy. The extent to which solar hot water systems save energy compared to conventional systems in Melbourne, Australia, is shown through a comparative net energy analysis. The solar systems provided a net energy saving compared to the conventional systems after 0.5 to 2 years, for electricity and gas systems respectively.

Solar versus fossil fuels : A net energy analysis of domestic solar hot water systems in Australia

It is commonly assumed that solar hot water systems save energy and reduce greenhouse gas emissions compared to conventional electric and gas hot water systems. Very rarely has the life-cycle energy requirements (including the embodied energy of manufacture) of solar hot water systems been analysed. The extent to which solar hot water systems can save energy compared to conventional electric or gas hot water systems can be shown through a comparative net energy analysis. This method determines the ‘energy payback period’, including consideration of the difference in operational energy savings and energy embodied in the devices relative to a base case. Dr Robert Crawford, Deakin University, Australia presents the results of a net energy analysis that compared solar and conventional hot water systems for a southern (Melbourne) and a northern (Brisbane) Australian climate.

Analysis of residues of prometryne and acetochlor in soil-water system by solid-phase extraction and gas chromatography/mass spectrometry

A highly sensitive and simple analytical method was developed for analyzing the binary mixed pesticides of prometryne and acetochlor in soil–water system by gas chromatography/mass spectrometry (GC/MS). The sample solution was first purified by C18 solid-phase extraction column, which was leached by acetone. The leachate was enriched to 1.0 mL by pressure blowing concentrator and then analyzed by GC/MS. The linear calibration curves were showed in the range of 1–15 μg/mL with a correlation coefficient of 0.9991. The average recoveries (n = 5) were between 95.3 and 115.7%, with relative standard deviations ranged from 1.71 and 7.95%. The limits of detection of Prometryne/Acetochlor were up to 0.06 and 0.17 μg/mL, respectively. This method provides a reliable approach to examine and evaluate the residues of prometryne and acetochlor in the soil–water system.

Dynamic performance of duolayers at the air/water interface. 1. Experimental analysis

Understanding, and improving, the behavior of thin surface films under exposure to externally applied forces is important for applications such as mimicking biological membranes, water evaporation mitigation, and recovery of oil spills. This paper demonstrates that the incorporation of a water-soluble polymer into the surface film composition, i.e., formation of a three-duolayer system, shows improved performance under an applied dynamic stress, with an evaporation saving of 84% observed after 16 h, compared to 74% for the insoluble three-monolayer alone. Canal viscometry and spreading rate experiments, performed using the same conditions, demonstrated an increased surface viscosity and faster spreading rate for the three-duolayer system, likely contributing to the observed improvement in dynamic performance. Brewster angle microscopy and dye-tagged polymers were used to visualize the system and demonstrated that the duolayer and monolayer system both form a homogeneous film of uniform, single-molecule thickness, with the excess material compacting into small floating reservoirs on the surface. It was also observed that both components have to be applied to the water surface together in order to achieve improved performance under dynamic conditions. These findings have important implications for the use of surface films in various applications where resistance to external disturbance is required.

Exceptional object analysis for finding rare environmental events from water quality datasets

This paper provides a novel Exceptional Object Analysis for Finding Rare Environmental Events (EOAFREE). The major contribution of our EOAFREE method is that it proposes a general Improved Exceptional Object Analysis based on Noises (IEOAN) algorithm to efficiently detect and rank exceptional objects. Our IEOAN algorithm is more general than already known outlier detection algorithms to find exceptional objects that may be not on the border; and experimental study shows that our IEOAN algorithm is far more efficient than directly recursively using already known clustering algorithms that may not force every data instance to belong to a cluster to detect rare events. Another contribution is that it provides an approach to preprocess heterogeneous real world data through exploring domain knowledge, based on which it defines changes instead of the water data value itself as the input of the IEOAN algorithm to remove the geographical differences between any two sites and the temporal differences between any two years. The effectiveness of our EOAFREE method is demonstrated by a real world application - that is, to detect water pollution events from the water quality datasets of 93 sites distributed in 10 river basins in Victoria, Australia between 1975 and 2010. © 2012 Elsevier B.V..

Analysis of mammalian cell proliferation and macromolecule synthesis using deuterated water and gas chromatography-mass spectrometry.

Deuterated water (²H₂O), a stable isotopic tracer, provides a convenient and reliable way to label multiple cellular biomass components (macromolecules), thus permitting the calculation of their synthesis rates. Here, we have combined ²H₂O labelling, GC-MS analysis and a novel cell fractionation method to extract multiple biomass components (DNA, protein and lipids) from the one biological sample, thus permitting the simultaneous measurement of DNA (cell proliferation), protein and lipid synthesis rates. We have used this approach to characterize the turnover rates and metabolism of a panel of mammalian cells in vitro (muscle C2C12 and colon cancer cell lines). Our data show that in actively-proliferating cells, biomass synthesis rates are strongly linked to the rate of cell division. Furthermore, in both proliferating and non-proliferating cells, it is the lipid pool that undergoes the most rapid turnover when compared to DNA and protein. Finally, our data in human colon cancer cell lines reveal a marked heterogeneity in the reliance on the de novo lipogenic pathway, with the cells being dependent on both 'self-made' and exogenously-derived fatty acid.