Zero Waste and Climate Change
The goals of zero waste are linked to reducing the impacts of climate change.
The National Greenhouse Inventory accounts for the greenhouse impact of waste only at the disposal end of the waste hierarchy. According to the National Greenhouse Inventory, the waste sector contributes 3% of national emissions, and of that, the vast majority is methane from landfills that is captured and recovered for electricity generation purposes. Based on this methodology of measuring greenhouse contribution, waste is a largely insignificant sector in relation to climate change.
This narrow focus on one part of the lifecycle means that the greenhouse impact of materials is only being measured once it becomes ‘waste’. This approach underestimates the climate change benefits arising from policies, investment, programs and activities that target the higher (preferred) end of the waste hierarchy.
Recycling resources that have already entered the human economy uses much less energy than mining and manufacturing virgin materials, and results in the following secondary (recycled) material energy savings:
- 95% for aluminium
- 85% for copper
- 80% for plastics
- 74% for steel
- 64% for paper.
(Source: Recycling International)
Through reuse and recycling, the energy embodied in waste products is retained, and thereby slows the potential for climate change.
Recycling will continue to be an essential part of responsible materials management, as the greater the shift from a ‘river’ (linear throughput of materials) economy towards a ‘lake’ (stock of continually circulating materials) economy, the greater the material and greenhouse gains will be.
Even so, recycling is only halfway up the waste hierarchy. The greenhouse gains lying in the upper half of the hierarchy (waste avoidance and reduction) are still largely untapped. The focus of attention needs to expand from the ‘downstream’ of the materials cycle (the post-consumer stage), to include the ‘upstream’ (the pre-consumer stage).
