Decarbonising the construction industry
Excitingly, the shift to renewable electricity production is moving faster than expected! What’s more, in big industries such as transport and logistics, business and asset owners are largely on-board with making the switch to all-electric.
This is made possible to a great extent by removing gas from building energy consumption along with great strides in electrification. For example, new constructions like the Atlassian tower and the Powerhouse Museum in Sydney have committed to be all-electric. Along with Melbourne’s Brimbank Aquatic Centre, an entire aquatic centre including an Olympic sized pool, powered using renewable energy. Hospitals have also traditionally been reliant on gas, but we now have three hospitals across Australia committing to be fully electric, including the new Women’s and Children’s Hospital in Adelaide.
While new construction and other industries are moving towards decarbonisation, the construction industry is lagging behind in the necessary technology required to eliminate embedded emissions. We take a look at what embedded emissions are, and how the construction industry can hope to move towards a net-zero emissions future.
What are embedded emissions?
Embedded emissions (also referred to as embodied emissions or embedded carbon) are the sum of greenhouse gas emissions required to bring a product to market. This includes emissions generated through raw material extraction/farming, processing of materials, as well as the manufacturing and transportation of the final product. Some definitions also include emissions associated with the use and eventual disposal of a product.
Building materials, especially cement which was responsible for 8% of global carbon emissions in 2015, have a significant climate impact. In fact, almost 10% of national greenhouse gas emissions come from embodied carbon and 28% of emissions come from the building and construction sector globally.
How can the construction industry reduce embedded emissions?
Extraction and production
Reducing embodied carbon starts with the raw materials. That’s why one of the best ways to reduce embedded emissions is to re-use and recycle to avoid the carbon-intensive process of extracting raw materials to make new products. Recycled building materials are more robust and available than ever before.
We won’t always be able to re-use or re-purpose an existing structure, so when a new building is required, take these important steps to reduce embedded emissions.
Use lower carbon concrete mixes by using fly ash, slag, calcined clays, or even lower-strength concrete where feasible. Limit carbon-intensive materials, such as aluminium, plastics, and foam insulation.
Waste
Australia generated 27 million tonnes of waste (44% of all waste) from the construction and demolition (C&D) sector in 2018-19. That’s a 61% increase since 2006-07. However, recycling rates and processing capacities still need to increase massively. The majority of C&D waste goes to landfill.
Facilities that can process and recycle this waste need to be developed in order to put these resources back into circulation. For example, much of the construction waste can be used in road building after processing.
The construction industry has a long way to go towards decarbonisation and focussing on embedded emissions will play a key role in the transition.