Lebenszyklusbewertung – Erfahrungen der australischen Ziegelindustrie

1 Introduction It is no secret that Australia has a very strong and efficient economy that benefits significantly from its natural and mineral resources. At the heart of the economy – perhaps unfortunately – is cheap energy fuelled by non-renewable resources. The availability of non-renewable resources is “perhaps unfortunate” because investment decisions in these energy supply systems was made during the 1960s and earlier before the double-edge sword of plentiful non-renewable resources had become apparent. Despite this, and despite the difficulty of climate politics currently occurring in Australia, there is significant work being undertaken under the radar which gives cause for optimism about Australia’s energy and greenhouse future. One such area of activity is Life Cycle Assessment (LCA). Spurred on by the success of kitchen and bathroom appliance energy and water rating labels, there has been increasing government and consumer demand for equivalent labels for other sectors of the economy, including buildings and building materials. Following on from similar European and American pro­jects, there has been considerable investment by both industry and government in projects that support an LCA approach to the measurement of buildings. Among the innovators are the Australian Green Building Council (AGBC), large commercial property builders and owners, but equally important work is also being undertaken by government and building material manufacturers to provide the necessary data and processes that ensure the AGBC rating systems (Green Star) and large commercial property builders are innovating in the right systems and technologies. This article is based on the Australian clay brick industry’s involvement in some of the many LCA-related projects currently being undertaken by stakeholders in the construction sector. It outlines the broad policy context, the results of the industry’s own two LCA research projects, and discusses some of the limitations of the ISO 14040 & 14044 Life Cycle Assessment methodologies when used in a policy framework to rate buildings and building materials.    2 The Australian LCA policy context Over the past two years the Australian clay brick and paver manufacturer’s industry association, Think Brick Australia, has been actively involved in many different aspects of Life Cycle Analysis (LCA), including: › Undertaking two LCA research projects: (1) a total LCA of the Australian clay brick industry and (2) a highly energy and water efficient demonstration house › Contributing to the joint Building Products Innovation Council (BPIC) project to develop the AusLCI (Australian Life Cycle Indicator) database of all Australian building materials inventory data for the completion of LCAs › Peer reviewing the Forest and Wood Products Australia’s full LCA on the impact of concrete slabs compared to suspended (timber) flooring systems › Membership of the National Standards1 Eco-labelling committee to develop a standard for the creation of product eco-labels › Development of an eco-labelling methodology specific to buildings with the Concrete Masonry Association of Australia (CMAA) › Chairing the Australian Sustainable Built Environment Council’s (ASBEC) Zero Emission Residential Task Group The rationale for undertaking these was: › to ensure the fair, equitable and accurate treatment of clay brick › to better understand the issue, its urgency, the key stakeholders, and its relationship to future policy changes › to take a leadership position in the building products market on carbon related issues, and › to benchmark the current industry position   3 The Australian clay brick industry‘s LCA results »1 graphically depicts the research methodology including four different assessments. It also demonstrates the methodology’s key strength: a very wide scope of analysis. The research modelled the total embodied and operational impact of two different detached house plans, in three climate zones, across four orientations and with five different walling systems. The locations chosen were Brisbane, Newcastle and Melbourne. The results demonstrate that when operational energy savings are taken into consideration (i.e. the use of heating, cooling, appliances and hot water), the embodied energy of a house – regardless of construction – only amounts to a maximum of 11 per cent of the total greenhouse gases over 50 years, and that the brick wall contributed less than one per cent of the impact. If only heating and cooling are considered (because walling construction does not impact appliance or hot water energy efficiency), embodied energy of the housing shell – regardless of construction – had a maximum impact of 55 per cent.Furthermore, depending on the location, using lower embodied energy building materials often increased the houses’ total greenhouse gas impact. For example, in the temperate climate of Newcastle, the house constructed in lower embodied energy building materials (insulated timber weatherboard) contributed 6.5 per cent more greenhouse gases than the house built with higher embodied energy building materials (insulated double brick) over 50 years (» 2). Energetics concluded that simply changing the walling construction from one material to another, without adopting other design considerations, had a maximum influence of between seven and 12 per cent on the total greenhouse gas impacts of the house over 50 years (and not always positive), and that the design of the house has a greater impact on the lifetime performance. Optimizing house design (including orientation) not only offsets higher embodied energy, but in a number of situations improves the long-term energy efficiency of a house. Overall, Energetics concluded that embodied energy in detached residential houses offers only small greenhouse savings compared to other aspects of a house such as equivalent savings by using more efficient lighting and solar hot water systems.   4 Improving policy Although there is an ISO standard governing LCA research, the research project highlighted many of its limitations: fundamentally, that the standard does not guarantee comparable LCA results. Unlike some other standards that have rigorous assumptions and objective methodologies, ISO 14040 and 14044 are subjective and act as a guideline for defining a tailored process based on specific outcomes sought. Prior to broader use of the LCA methodology in policy frameworks, a standardized methodology, set of assumptions, and data collection process are required. Part of this work is being done through a unique collaboration in the building products sector. The BPIC AusLCI project has been working for the past two years to develop a standard methodology for the collection of inventory data across the building products sector. The outcome will be a freely available national database of LCI data collected using a standard methodology. Although a landmark outcome, unfortunately this on its own is not sufficient to remove the subjectivity of the ISO LCA methodology. Still required is the standardized methodology for how LCI data is used in an LCA research project. Although it is yet to be endorsed by the broad property, construction and eco-labelling groups, the BPIC group has recently come to agreement on the starting point for such a standardized LCA methodology. The advantage of a standardized methodology, set of assumptions, and data collection process is to manage the increasing number of sales and marketing claims supported by LCA-related research. Many companies are now undertaking LCAs in response to both consumer concerns and accusations of greenwashing, yet it has created a new challenge: ensuring customers, when comparing the LCA results from different products, are making like-with-like comparisons. Similarly, in the education sector, students and academics alike are turning to LCA because of its “objectiveness”, without realizing that the entire LCA methodology and governing standard is subjective. Furthermore, LCA’s do not only measure the carbon dioxide equivalents, they can include any number of impact categories such as (but not limited to) Volatile Organic Compounds (VOCs), water consumption, land use or air pollutants. The significance and weighting of these other environmental impacts depends upon the intended use of LCA. These issues have been particularly difficult for the BPIC group to come to agreement on. Despite the immediate policy challenges facing the broader use of LCA in Australia, the appetite for this kind of information does exist, and good built-environment outcomes are appearing from a sector that has given serious consideration to its contribution and involvement in the global climate change challenge. For more information on the Australian brick industry’s LCA research, visit the blog site to find the full report, summary report and additional commentary on the methodology and policy implications: http://blog.thinkbrick.com.au/sustainability/lca/ 1 „National Standards“ should not be confused with Australia’s national standards organization, Standards Australia. National Standards is a private standard-writing organization that has applied for the rights from Standards Australia to develop the national standard for eco-labels in Australia.