Kuruvilla Mathew

Solar energy has a major role in moving towards carbon neutral settlements. Three different Australian settlement types are included in this research: urban villages, remote indigenous settlements and isolated mine site camps. This study contributes to a broader ARC research program by Curtin University and Murdoch University on Decarbonising Cities and Regions. A six-element model for carbon neutral human settlements was developed. This was subsequently upgraded to include food as a separate element. The process to achieve a carbon neutral settlement via an emissions reduction plan, following a life cycle analysis, was proposed in six steps. It was found that this planning method can enable new urban developments to achieve a ‘zero energy development’ but achieving a carbon neutral status would require additional measures that address the complete lifecycle of the development. Monitoring and data collection systems were installed in a minesite camp and the data used in a new modelling tool to evaluate different renewable energy systems to offset total lifecycle emissions. These systems were found to only reduce emissions below that of the existing gas-fired power generation somewhere between 2013 and 2018 when costs are expected to drop significantly. In the case of remote indigenous settlements the elements of this planning model were used to identify opportunities for sustainable livelihoods linked to renewable energy in the new carbon economy.

This paper presents a model for carbon neutral land development as a mechanism to help drive innovation and emission reduction within the built environment sector. The carbon content model is comprised of the following: • The greenhouse gas (GHG) embodied in the materials of the buildings and the infrastructure; • The GHG emitted during the construction process with different approaches; • The electrical power and natural gas used in the buildings for different building types; • The transport fuels used in the construction and the on-going use by residents; • The GHG produced in the full water cycle • The GHG from the solid waste. Understanding the interactions between the six elements of the model allows better decarbonisaton options to be developed. Two remote settlement cases are analysed. Firstly for a mine site camp, we introduce the “Smart Camp” digital control and monitoring concept . This includes sustainable village design, heating and cooling reduction, renewable energy, water use and reuse, and landscaping. Secondly, for the remote Aboriginal settlement, we address the need for sustainable livelihoods, including local food production and rangelands forestry and management.

The process to achieve a carbon neutral settlement via an emissions reduction plan, following a life cycle analysis, is in five steps: 1) Understanding energy use, 2) Behaviour change programs, 3) Energy efficiency improvements, 4) Monitoring and control, 5) Renewable energy technologies, and 6) Biosequestration as a sink for the balance of past, current and ongoing emissions. Three cases typical of Australia are analysed with this six-step reduction model: the urban village, the remote minesite camp and the remote Aboriginal settlement. Following extensive research a carbon reduction plan has been developed for each case.

Earthworms due to their peculiar feeding habits and habitats are commercially utilised in waste management, fish food and fish baits. They also have been proved to be versatile tools for the environmental monitoring and ecotoxicology. The garden earthworms are known to improve the soil quality and crop production, while certain species are ideal for commercial applications for waste management. Maintaining the system within the tolerance level of each commercial species is important for the successful operation of the vermicomposting or vermiculture systems. Domestic vermicomposting toilets can be used in National Parks (campsites), isolated roadhouses, farmhouses, and on peri-urban or semi-rural blocks under current legislation in Australia. Their use is ideal in places where disposal of effluent is difficult due to low soil infiltration, lack of availability of land, limited water resources, or in ecologically-sensitive areas. A greywater recycling system may still be needed where wet facilities are required. The mature vermicompost product is free of pathogens, ideal for the garden and results in a cycling of the nutrients. The domestic vermifiltration system can replace septic tank systems. This system avoids the need for periodic pumping of sludge as well as the need for two separate systems. Again vermicompost is produced for the garden and the treated effluent can be recycled on the garden by subsurface irrigation. Any system that requires disposal of effluent from septic tanks can use the vermifiltration method.The Vermitech sludge stabilisation process uses the same vermicomposting principles and can process successfully sewage sludge from municipal sewerage facilities as well as a range of other organic wastes. A design procedure for loading of organic matter has been developed and varfied with the present pracice of loading in the vermocompost treatment plant in Redland, Queensland Australia. If the loading is full of organic matter it is possible to load a maximum of 2 to 4 cm per day. Any thing more shall create an aerobic condition and the process will be difficult. It may be possible to take an average of 10 to 20cms per week.

Around the world there is a paradigm shift occurring, one that is moving away from traditional centralised wastewater infrastructure towards decentralised wastewater system options. In Western Australia (WA) the development of decentralised systems has been slow. However significant steps have been made towards making decentralisation a reality, with several innovative technologies based on natural biological processes being trialed, such as constructed wetlands. The WA State Government is investing research in practical case studies that will assess the viability of decentralised wastewater schemes, within WA urban villages. The research is to be conducted over three years starting with two decentralised greywater systems, progressing in the final year (2008) with research into combined wastewater systems. The first case study site, Bridgewater Lifestyle Village (BWLV) located in Erskine south of Perth, will encompass 380 individual greywater systems that are centrally managed with the treated greywater used to irrigate the gardens of each home. The second site, Timbers Edge Residential Resort (TERV) located in Dawesville also south of Perth, will encompass 260 homes connected to one centrally managed greywater treatment system, with the treated greywater being used to irrigate the estates public open space. Both of these sites are located in a high population growth corridor adjacent to the Peel Harvey Estuary; are within close proximity to RAMSAR5 protected wetlands; and experience high water table levels. In order to meet environmental and public health concerns, innovative solutions would be required. Each site employs a wastewater treatment and recycling system that mimics natural processes. This paper will introduce two types of subsurface constructed wetlands that are either operating or will be operating in the near future at the two case study sites. The first system discussed is the evapotranspiration trenches at BWLV. These are a low maintenance biological system consisting of a plastic lined gravel-filled trench planted with various hardy aquatic plants and will be placed in home sites where the groundwater table is higher than 50cm. The second system at TERV is known as the Biofilter system and consists of a series of concrete chambers planted with wetland plants. This paper will then discuss how these systems recycle the water locally to reduce water demand; what the residents’ responsibilities are and how different management arrangements can effectively manage and operate these systems.