Direct CO₂ emissions in the Australian buildings sector have been rising steadily since 1990, with 2019 showing a rare small year-on-year decline. As of 2019, electricity holds a 60% share of the buildings sector energy mix while gas has a 26% share.
Australia has a high, and increasingly rapid, uptake of rooftop solar. Recent analysis shows that the country’s residential solar share of total power capacity is around 15%, making Australia a global leader in this regard. The number of small-scale rooftop solar systems in Australia exceeds 3 million, generating about 7% of Australia’s total power. Capacity additions of small-scale solar have grown by an average 39% year on year since 2016, while the average size of rooftop solar systems increased threefold over the past decade.
Apart from how energy is supplied, reducing total energy demand from buildings should also play a role in emission reductions in the sector. Accordingly, the Australian government has recently updated the National Construction Code to increase the energy efficiency of new residential buildings. This is in line with an earlier plan to set a trajectory for net zero energy buildings.,
A 1.5°C compatible pathway would see electricity’s share of the buildings sector’s energy mix increase to 78-81% by 2030 and 92-94% by 2050. This would be in conjunction with an increasing share of renewables in power generation (81-88% by 2030, 100% by 2040). With increasing renewable-based electrification in the buildings sector, and the introduction of other renewable fuels (i.e., hydrogen), fossil gas’ role in the fuel mix would decline.