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Executives are keen to draw workers back to the office – but many workers are not on the same page.

New research from UNSW Sydney has identified a pathway to net zero – and even net negative – emissions by 2050 for Australia’s residential and commercial buildings, and improve the United Nations Sustainable Development Goals (SDGs).

The project, headed by Dr Cameron Allen in the Sustainability Assessment Program, School of Civil and Environmental Engineering, modelled operational and embodied greenhouse gas (GHG) emissions in a national-scale integrated macroeconomic simulation model to explore coherent pathways to achieve the goal.

Co authors of the work were Philip Oldfield, Soo Huey Teh and Thomas Wiedmann of UNSW, Sarah Langdon of University of Technology Sydney, Man Yu of CSIRO Brisbane and Jiajia Yang of UNSW

The project was reported in an article, Modelling ambitious climate mitigation pathways for Australia’s built environment“, published by Sustainable Cities and Society in November.

Business as usual will fail

Several scenarios were modelled. While “business as usual” will not achieve sufficient emission reductions, the high ambition scenario that was modelled delivered a 94 per cent reduction in GHG emissions from buildings by 2050, and an improvement in Australia’s overall SDGs performance.

The changes we must make

Scenario 2 (the high ambition scenario) assumed that buildings are 100 per cent electrified (no gas or other fossil fuels consumed) by 2050 and that 30 per cent of larger buildings are constructed from mass-timber.

Achieving the reductions also requires a shift to renewable energy,

improving energy efficiency, replacing carbon-intensive materials, and reducing end-of-life losses in sequestered carbon. It also assumes 100 per cent electric vehicles by 2050.

Recent ABS statistics showing that the total distance travelled by electric vehicles in Australia is already more than internal combustion vehicles shows that vehicle superusers are already ahead of the game. With this in mind, the 100 per cent electric vehicles by 2050 doesn’t look too ambitious, despite government inaction.

Populate and sequester

A potentially controversial pathway to achieve net zero or net negative emissions by 2050 is to gradually increase net immigration towards 2050 – to a level slightly higher than pre-COVID-19 but lower than during the Rudd government. These are the correct numbers, correcting a typographical error in the publication.

Over time, the increase in population can be balanced against the benefits of rapid decarbonisation of other parts of the economy  and an increase in carbon sequestered in timber in building materials. Critical to achieving this beneficial effect would be the sustainable management of timber at the end-of-building life. 

No single solution

The research conclusions say that there “is no ‘silver bullet’ to reach net-zero and that a combination of measures will be required. It also highlights the benefits of applying a macro-scale integrated assessment modelling framework to explore combinations of policy settings and different pathways that ensure policy coherence between different interventions. Incorporating an assessment of progress on the SDGs into sectoral analyses also provides a mechanism for evaluating broader policy coherence with other socio-economic and environmental objectives of importance for national sustainable development.”

In short, there is hope, we can do it, but we’re going to have to change.

In some sectors, like the transition to electric vehicles, we are on the way. In other areas, like increasing energy efficiency in our buildings, and a widespread switch to low carbon materials, we need to take action now, and manage future effort by measuring and managing all factors holistically.

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  1. Hello Damian, regarding your comment on building and ‘mass timber’. We have an excellent alternative to timber, stronger than concrete and beautiful besides. See our website: We can leave the trees where they are! Bamboo grows 78 times faster than trees and sequesters at least 30% more CO2. Would be interested to hear your thoughts.