RP3009: High Performance Housing

_{Peer Reviewed Research Publications}

RP3009: Journal Article: Quantifying radiation from thermal imaging of residential landscape elements

The microclimate of a residential landscape can affect both the energy use in your home and the human thermal comfort in your garden, ultimately affecting the heat in the neighbourhood or precinct. A thermal imaging camera provides information about the temperature of surfaces. By using Stefan–Boltzmann’s law and the surface properties, these temperatures can be used to calculate the emission of longwave radiation (radiant exitance) in W m−2.

A thermal camera was used to determine the amount of radiant exitance from a range of residential landscape elements.A standard procedure for capturing these images was developed, taking into account factors which affect the quality of the radiometric data. A quantitative database comparing this radiation has been compiled for different times of day and different seasons. The sky view factor of these elements was chosen such that it was as close to 1 as possible. For a particular landscape design, areas of each landscape element can be measured and the amount of radiation reduced or emitted at different times can be calculated.

This data can be used to improve landscape designs to reduce home energy use and human thermal comfort through shading and reduction of surfaces which emit longwave radiation close to the house.

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RP3009: Journal Article: Verification of an emerging LCA design tool through real life performance monitoring

Recent research has demonstrated that low-emission houses often underperform, consuming more energy than predicted by their designs. Life cycle assessments (LCA) have been employed to complement mandatory energy assessments, as they offer a more comprehensive evaluation of greenhouse gas (GHG) emissions over the building lifespan.

This research monitored ten energy efficient Australian houses and recorded data about energy use and photovoltaic generation over 1 year. The houses were assessed with a relatively new LCA tool in addition to the Australian mandatory house energy assessment Nationwide House Energy Rating Scheme (NatHERS).The objective of this study was twofold: first, to evaluate the results of the assessment tools compared to actual house energy requirements and second, to understand how design, renewable energy, and occupancy can impact the overall GHG emissions of the houses.

The results show that energy use is positively related to NatHERS ratings, but some of the high performance houses perform poorly and there was significant variation in energy use between houses with the same ratings. The LCA revealed that modern houses have higher embodied energy than older houses, while solar panels are not always used to their full potential. This paper attributes some of the variations between theoretical and actual energy use to construction issues and occupant practices.

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RP3009: Journal Article: Josh's battery - a more even relationship with the grid

Josh's House is a “living laboratory” research and demonstration project in the Perth suburb of Hilton, Western Australia. The scope of Josh's House included the design and construction of two energy efficient family homes that achieved the highest level, 10-stars (estimated thermal load: 4 MJ/m2/year) [Australian Government Department of Environment, Star rating scale overview, 2015 (Online), http://www.nathers.gov.au/owners-and-builders/star-rating-scale-overview, accessed on: 2017/17/07], under the Nationwide House Energy Rating Scheme. The project partners include the Co-operative Research Centre for Low Carbon Living and Curtin University.In mid-2015, a further research component was added to Josh's House involving the installation and ongoing monitoring of a battery storage system. This system is a domestic example of a distributed energy storage system (DESS) and is here referred to “Josh's Battery” or “the DESS”.

The aim of the project is, in the first instance, to make domestic DESS data publicly available. Broader project objectives are to trial the technology, test assumptions on performance, document and communicate lessons and outcomes, and to inform further research and development.This paper provides an analysis of the monitoring data produced during the energy storage system's first year of operation. Particular areas of interest include: interaction with the electricity grid before and after installation of the storage system; correlation of system performance to specifications and modelled predictions; anomalies and unexpected results; and lessons learned from the installation and operation of the system. Implications and influences. The significance of this research is that it is built around the first monitored, grid connected domestic energy storage system in the Perth metropolitan area. It provides unprecedented data on how these systems can be expected to operate when embedded into a large-scale electricity network. The project also gives the opportunity to test some fundamental assumptions about these systems and feed into policy and business case development for the distributed energy storage sector, more broadly.

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RP3009: Journal Article: The home as a system of practice and its implications for energy and water metabolism

Policy and regulations for residential houses often consider the physical system alone and tend to focus on the energy performance of the building. This ignores the effect of occupants’ everyday practices and their interaction with the building technologies. This research applies practice theory and the concept of system of practice to eight Australian homes with the objectives of providing a deeper understanding of the complexities of the home system as well as providing approaches to enable (rather than persuade) resource reduction. The homes were investigated through explanatory design mixed methods which combined results of one year of longitudinal quantitative data collection and home occupant interviews.

The results revealed that practices are performed in a sequential temporal spectrum as part of a routine and are influenced by interlocked practices as well as interlocking routines from other home occupants. Practices also follow established daily patterns reflected by a frequency distribution curve where the standard deviation reflects the degree of habituality of the practice. Highly interlocked practices with a high degree of habituality are challenging to affect. However, automation could enable resource intensive activities to be dis-interlocked from an established routine and make change within the home system of practice easier and more flexible.

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RP3009: Journal Article: A technique for quantifying the reduction of solar radiation due to cloud and tree cover

The micro-climate of a domestic residential landscape can affect both the energy use of the dwelling and the human thermal comfort within that landscape. Radiant energy produced from, or reduced by different landscape elements such as trees, and hard and soft surfaces, directly affects the amount of heat incident on the walls of the residence or on people present in the garden. Quantifying this energy will enable the development of a relative scale of thermal performance for these elements and consequently for the landscape as a whole. This gives a measured consequence for each landscape design, allowing comparisons and hopefully improvements, between and within designs.Radiant energy is produced from direct or diffuse solar short wave and infrared radiation and longwave radiation from heated landscape elements.

This paper presents a technique which has been developed for inexpensively and easily estimating the amount of incident radiation reduced by cloud and by three different tree types. The measurement surfaces of cheap temperature sensors with data logging capabilities (iButtons) were coated with either a white gloss or a matt black paint. White gloss paint has an emissivity of ∼0.9 in the longwave spectrum but only ∼0.3 in the short wave, whereas matt black paint has an emissivity of ∼0.95 for both and can be used to detect both short and long wave radiation. The temperature difference between the two gives a measure of the amount of shortwave radiation or visible light. This enabled measurements of cloud shade and local plant shade, and an estimation of the quantity of that shade when compared with full sky exposed reference iButtons. The iButtons can be mounted concurrently at numerous points around a house envelope or in a landscape, at multiple house locations to determine the quantity of shade provided by different native and introduced plant species.

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RP3009: Journal Article: Influencing energy and water use within a home system of practice

Approaches that attempt to influence resource use in the home often consider the building system alone, without due consideration of occupants and their practices. However, occupants interact with technology and ultimately affect energy and water metabolism in the home.

This research used an explanatory design mixed method approach to investigate the energy and water use in eight homes over a two-year period, before and after an intervention based on persuasive behaviour change. Each home was considered as a system of practice and results were analysed in terms of overall resource reduction, changes in practice and changes made to the building systems. It was revealed that five of the homes succeeded in reducing their resource use through the two years. Most changes were achieved through affecting technology as an element of practice. Automation was shown to enable the dis-interlocking of practices from aligned and interlocked routines and can be considered an effective solution to influence resource use in the home.

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RP3009: Journal Article: Unraveling everyday heating practices in residential homes

Recent research has found that low-emission buildings do not necessarily meet their full theoretical energy saving potential and one of the reasons for this discrepancy is related to occupancy. Inside the building, users interact with technologies and are influenced by everyday practice and subsequent behaviour.

This research aims to unravel the layers of complexity in everyday practice with regards to heating and the use of renewable energy. For this purpose, ten Australian houses were established as embedded Living Labs and monitored for over a year. Results show that the studied households use climate control at different times of the day depending on lifestyle. However, individuals in the same household may have different heating practices according to motivations, attitudes and subjective norms. The combination of quantitative monitoring and qualitative assessments revealed that lifestyle, family structure, habits, comfort and the presence of renewable energy all impact on the frequency, timing and intensity of heating and cooling practice. This research provides a better understanding of intra-home and everyday practices, helping to inform the transition from energy efficient houses to energy efficient home systems.

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RP3009: Journal Article: The influence of design and everyday practices on individual heating and cooling behaviour in residential homes

Emerging results from practice-based research demonstrate that energy efficient houses often do not meet theoretical energy use based on the current standards of residential buildings. A factor influencing this inconsistency is related to user behaviour and everyday practices. The objective of this research is to uncover some of the complexities associated with the practices of heating and cooling in the home, which are influenced by motivations, knowledge and technologies, including the use of photovoltaic panels.

For this purpose, ten Australian houses were established as embedded Living Labs and monitored for over a year. The results confirm the variation of energy use in houses; in this case, similar designs vary by up to 33%. The type of heating and cooling systems that houses rely on through the year was found to be a major determinant in energy use. However, energy variation between houses is also linked to intra-home practices and behaviours. This research found that individuals living in the same house may have different motivations and/or heating and cooling practices, affecting the overall energy use. For instance, one individual who is motivated to save on energy bills might turn on appliances during the day to make the most of solar panels or use the heater for brief periods of time, whilst another inhabitant of the same house might turn on the heater for extended periods out of habit or to achieve a hedonic experience. The adoption of an explanatory design mixed-method approach to study everyday practices in the home showed that the routines, household configuration, technology and varied occupant motivations impact on the practice of ambient heating and cooling, impacting its regularity, duration, time of the day and intensity.

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RP3009: Journal Article: WGV: An Australian urban precinct case study to demonstrate the 1.5 °C agenda including multiple SDGs

The WGV project is an infill residential development in a middle suburb of Perth, Western Australia. Its urban planning innovation is in its attempt to demonstrate net zero carbon as well as other sustainability goals set by urban planning processes such as community engagement and the One Planet Living accreditation process. It is a contribution to the IPCC 1.5 °C agenda which seeks to achieve deep decarbonization while also delivering the UN Sustainable Development Goals (SDGs).

Solar photovoltaics and battery storage are incorporated into the development and create net zero carbon power through an innovative ‘citizen utility’ with peer-to-peer trading. The multiple sustainable development features such as water sensitive design, energy efficiency, social housing, heritage retention, landscape and community involvement, are aiming to provide inclusive, safe, resilient and sustainable living and have been assessed under the SDG framework. 

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RP2009: Conference paper: Optimising residential water efficiency - the Josh's House project

Josh’s House is an innovative housing project in the suburb of Hilton, Western Australia consisting of two 10 Star NatHERS rated homes which are demonstrating a novel approach to the truly integrated design and implementation of residential urban water management supported by a uniquely high profile media campaign for the wider dissemination of knowledge to both the public and industry.

This paper describes the design intent, implementation and commissioning of the waterbased components of the project and how its performance is being monitored with both building designs and performance data being made available to the wider community.

rp2009 optimising residential water efficiency conf (966563 PDF)