Measuring our ecological footprint

15 March 2002

Researchers in the School of Physics have carried out the world's first compre-hensive case study of a university's environmental impact.

Dr Manfred Lenzen and third-year student Richard Wood have conducted a holistic assessment of the "ecological footprint" (EF) of the School of Physics, using methodology developed by Dr Lenzen and Shauna Murray from the School of Biological Sciences based on economic input-output analysis. This footprint is expressed as the total area of land required to support the operation of the institution indefinitely.

The School of Physics was found to have an ecological footprint of about 800 hectares - or 6.8 hectares per employee. This figure can be compared with the ecological footprint of the average Australian, which is 7.2 hectares per person.

"However, comparing our footprint with the global available space of 1.7 hectares per person shows that we are by far exceeding our equitable share", said Mr Wood.

The largest impact was from electricity use (14 per cent), followed by air travel (four per cent), electricity used by other campus services such as administration, security, or catering (three per cent), and electricity used by manufacturers to make electronic equip-ment that is bought by the School. Paper and books accounted for only 0.1 per cent of the EF.

The researchers also applied their footprint method to the Sustainable Ecosystems Department of the CSIRO (CSE), so that they could compare a research institution with a technological focus and a research institution more dependent on human resources. CSE's ecological footprint amounted to about 1400 hectares, but on a per employee basis, it was only 4.8 hectares. Electricity use accounted for 27 per cent of this EF, followed by the physical impact of the large CSE site (five per cent) and the emissions impact of air travel (four per cent).

The study identifies all contributing indus-trial input paths into the School of Physics' final environmental impact. Amongst these are complicated supply chains, such as the land used for beef cattle grazing which is required for producing food used in catering and hospitality. The complexity of these supply chains means that as much as 75 per cent of the impact occurs at three or more levels of separation away from the School of Physics, and is spread out across the whole of Australia and even overseas.

Dr Lenzen said previous studies have not been comprehensive because they have cut off the calculation at the first level of suppliers, and have not explored higher-order impacts. This results in a serious underestimation of the ecological footprint, he said. But input-output analysis can be used to provide a comprehensive picture of an institution's impact, and presents the material and energy flows in a transparent way.

An important application of the methodology developed by the Sydney researchers is its potential as a policy and planning tool for the sustainable development and operation of institutions. It can be used to both monitor and improve the effectiveness of an institution's environment management system.

"An EF can provide very useful information, especially for commercial and public organisations that can control and direct their own purchasing," said Dr Lenzen. "This is particularly true for universities, which, along with exerting control over expenditure, have a particular responsibility in being role models for best environmental practice.

"By incorporating the EF into an environmental management system and monitoring it over time, it would be possible to see whether more sensitive environ-mental policies - such as a commitment to green energy sources, an increase in video-conferencing to reduce air travel, an increase in recycling facilities to reduce the quantity of garbage, and switching to recycled paper - result in a reduction in environmental impact.

"The University of Sydney has committed to environmental change through the formation of a draft environmental policy in 1999, and a study of this nature can reveal whether actual change is occur-ring in real terms."

Contact: Jake O'Shaughnessy

Phone: +61 2 9351 4312 or 0421 617 861