Net Energy Analysis of Double Glazing for Residential Buildings in Temperate Climates

Energy used in buildings is a major contributor to Australia’s energy consumption and associated environmental impacts. The advent of complex glazing systems such as double glazing, particularly in northern America and Europe, has partially closed a weak thermal link in the building envelope. In milder climates, however, building envelope features may not be as effective in life cycle energy terms, i.e. including the embodied energy of their manufacture. A net energy analysis compares the savings in operational energy to the additional requirements for embodied energy, in terms of the energy payback period and energy return on investment. The effectiveness of double glazing is determined for an Australian residential building. A wide range of building operation regimes was simulated. These results support the principle of installing double glazing in residential buildings in Melbourne, Australia, at least in terms of net primary energy savings.

Comparative greenhouse emissions anayalsis of domestic solar hot water systems

It is commonly assumed that solar hot water systems save energy and reduce greenhouse emissions relative to conventional fossil fuel-powered systems. Very rarely has the life-cycle greenhouse emissions (including the embodied greenhouse emissions of manufacture) of solar hot water systems been analysed. The extent to which solar hot water systems can reduce emissions compared with conventional systems can be shown through a comparative life-cycle greenhouse emissions analysis. This method determined the time it takes for these net greenhouse emissions savings to occur, or the 'emissions payback period'. This paper presents the results of a life-cycle greenhouse emissions analysis of solar hot water systems in comparison with conventional hot water systems for a southern (Melbourne) and a northern (Brisbane) Australian city.

Life-cycle energy analysis of building integrated photovoltaic systems (BiPVs) with heat recovery unit

Building integrated photovoltaic (BiPV) systems generate electricity, but also heat, which is typically wasted and also reduces the efficiency of generation. A heat recovery unit can be combined with a BiPV system to take advantage of this waste heat, thus providing cogeneration. Two different photovoltaic (PV) cell types were combined with a heat recovery unit and analysed in terms of their life-cycle energy consumption to determine the energy payback period. A net energy analysis of these PV systems has previously been performed, but recent improvements in the data used for this study allow for a more comprehensive assessment of the combined energy used throughout the entire life-cycle of these systems to be performed. Energy payback periods between 4 and 16.5 years were found, depending on the BiPV system. The energy embodied in PV systems is significant, emphasised here due to the innovative use of national average input–output (I–O) data to fill gaps in traditional life-cycle inventories, i.e. hybrid analysis. These findings provide an insight into the net energy savings that are possible with a well-designed and managed BiPV system.

Embodied energy analysis of the refurbishment of a small detached building

Energy efficient design principles and the minimisation of operational energy requirements have been demonstrated in the refurbishment of a small existing residential building. Significant thought has been given to these areas, together with an emphasis on the minimisation of resource consumption and material wastage. However, less consideration has been given to the embodied energy of the additional materials, components and systems required to meet these aims. The additional embodied energy may reduce the advantages of minimising the operational energy consumption by extending the energy payback period beyond the life of the building. In general, the embodied energy of buildings and their products has been found to be significant, when national average input-output data is used to fill gaps in traditional life-cycle assessment inventories. Through the use of an input-outputbased hybrid embodied energy analysis, the embodied energy of this refurbished building has increased by 63% compared to the existing building, showing the impact that filling the gaps in traditional inventories can have on energy payback periods.

Seasonal storage for solar thermal systems in Australia?

Seasonal storage systems have been operating in various European countries since 1985. Combined with solar collectors, these systems are known as ‘central solar heating plants with seasonal storage’ (CSHPSS). While these systems have been shown to be technically feasible, their cost is still too high to make them competitive with fossil fuels.

In Australia, we have quite different conditions to those countries where CSHPSS have been trialled. In general, we experience higher radiation levels, ambient temperatures and cooling loads. Our heating loads and energy prices are also usually lower. As a result, any evaluation of CSPSS operating in a European context may not be valid for Australian conditions. To the authors’ knowledge, no evaluation of these systems has been carried out for Australia.

This paper therefore attempts an initial assessment of these systems and their viability for Australia. The paper first describes the various types of CSHPSS and then reviews their current status. The performance of one type of CSHPSS operating in several locations of Australia has been predicted using a TRNSYS model. The simulations indicated that the design guidelines for Europe are inappropriate for Australia and would result in greatly over-sized systems.

An indication of the financial viability of the system was determined by calculating a simple payback period for a variety of fossil fuels. This type of seasonal storage systems appears to be financially attractive in areas of southern Australia where the solar system is displacing LPG.

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.

A greener house : the sustainable property investor's guide to buying, building and renovating

Sustainability is now an integral part of society and the built environment. Unfortunately many home owners and home-buyers are unaware of the relationship between sustainability and value, especially with regard to the potential added value to their home. Payback periods can be different depending on factors such as the initial capital outlay and the levels of depreciation and obsolescence, as well as savings made (if any) to the running costs of the home

Evaluation of a heat pump system for greenhouse heating

Greenhouse heating costs for some commercial growers in southern Australia are now a significant production cost. This is particularly the case for those operators who installed heating systems using liquefied petroleum gas (LPG) when this fuel was relatively inexpensive. Heat pump systems used in various configurations have been suggested as an option for reducing energy use and costs for greenhouse heating, particularly if off-peak electricity is used. This paper investigates the financial and environmental viability of an air-to-water heat pump system for a 4000 m2 greenhouse, located 120 km north of Melbourne, Victoria. The simulation software, TRNSYS, was used to predict the performance of the system. The heat pump system was found to have a simple payback period of approximately six years and reduce LPG consumption by 16%. Greenhouse gas emissions were 3% higher using the heat pump system, compared to the existing LPG boiler.

Re-framing the riot : journalism, creative non-fiction and telling the story of Australia's black history

On 19 November 2004, an Aboriginal man was arrested on Palm Island, off the coast of Townsville in northern Queensland. He was taken to the local watch house on a drunk and disorderly charge. An hour later, he lay dead on a cell floor. His liver, an autopsy showed, had been split in half and his spleen ruptured. But when that autopsy report also found that Mulrunji Doomadgee’s severe injuries were not caused by force, the Palm Island Indigenous community, enraged and grief-stricken, went looking for payback.

The Palm Island “riots” ensured that this Aboriginal death in custody made international news headlines where others barely got a mention, if at all (Hollinsworth, 2005). The ensuing Coronial Inquest and criminal prosecution of the arresting Queensland police officer, Chris Hurley, also were covered consistently by the news media. Senior Sergeant Hurley has, however, so far escaped punishment and the Queensland media’s most recent report of the case was to tell how the Qld Police Union now funds a legal bid to clear his name. Meanwhile, little is heard in the news media of the Doomadgee family, the Palm Island community, or of other deaths in custody occurring steadily through the 18 years since the Royal Commission that was supposed to implement a raft of preventative recommendations.

While the news media’s framing of these issues has most often followed historically predictable and ultimately racist lines, a work of creative non-fiction tells the story with warranted complexity and power. Chloe Hooper’s The Tall Man: Death and Life on Palm Island documents Cameron Doomadgee’s death, the riots, and the ensuing legal farce from the front row. Hooper, in the tradition of Truman Capote, arrived at Palm Island as a white writer from a big city. But by “walking the talk” – being with the Doomadgee family and their community through the hearings and after, Hooper was given extraordinary access to community, history, and significant cultural nuance barely identified by, let alone understood by, non-Indigenous readers.

By focussing on Hooper’s experience with sources and court reporting, compared with some print media coverage, this paper will consider the comparative roles of journalism and creative non-fiction in re-framing the Palm Island “riot”. It will suggest that Hooper’s work subverts some dominant (and racist) news media representations of Australian Indigenous peoples through its use of source relationships in an extended narrative structure.

Raw materials and process chemical recovery in industrial wastewater pollution control

This article illustrates the different methods employed to recover raw materials and process chemicals in various industries. Although only a few industries such as car painting, metal cutting, electroplating, textile, abattoir and pesticide formulation have been illustrated in case studies, almost all the industries can recover raw materials and process chemicals from their waste streams. The case studies show that the investments on new processes or systems used to recover raw materials and process chemicals have a short payback period and hence bring huge savings to those industries. Thus, each industry should try to recover raw material and process chemicals from waste streams.

Defining and developing an energy retrofitting approach

This paper identifies the dilemma faced by the stakeholders of existing buildings in regards to a decision making process for energy retrofitting. This paper also identifies the missing stage viewed as the “integrity audit “which can lead to substantial savings in the area of building operation. The methodology is centered on identifying energy waste first, reducing the overall peak electrical demand and then retrofitting for energy-efficiency. A proposed “integrity audit” leads to the classification of three main energy culprits: the identification of waste, missed opportunities, and rescheduling the operation of equipment use. A case study indicating the financial advantages of applying this methodology for a commercial building are presented. The energy retrofitting strategy is divided into two main categories, namely building control improvements and building component implementation. The payback periods are often within months if not immediate.

Solar heating for commercial swimming pools – experiences in south-eastern Australia

Commercial swimming pools, particularly aquatic centres are increasingly common features of large towns and cities in Australia as people are encouraged to increase their levels of physical activity. Swimming is regarded as a low impact form of exercise and use of indoor facilities allows this to continue all-year round. Aquatic centres are large users of energy for water and space heating with an energy intensity which can be up to seven times that of a commercial office building in Australia. Much of the energy is used to heat water to relatively low temperatures and therefore solar energy technology is capable of providing this energy. In the residential sector, solar thermal systems for heating water and swimming pools is well-established. This is not the case for commercial swimming pools i.e. aquatic centres. In Victoria, a program to encourage commercial pool operators to install solar systems was funded in the early 1980s. This paper describes an investigation into the current use of and attitudes to solar systems in commercial pools through a survey of municipal pool operators in Victoria, south-eastern Australia. The survey found that there has been very little increase in the use of solar energy and that barriers to the use of the technology remain the same as they were nearly 30 years ago. Lack of roof area, poor payback periods and an inability of solar to meet pool heating needs are the most common misconceptions. To improve the uptake of solar heating in commercial pools, further research, particularly looking at the feasibility of integrating traditional heat sources with solar collectors using smart control, is required. An incentive programme and the education of the new generation of consultants and aquatic centre operators, unfamiliar with the potential benefits of solar systems, would also help to increase their uptake.