Scottish Waste Environmental Footprint Tool (SWEFT)

We are living in climate and nature crisis and need to introduce measures that can effectively help us tackle climate change rewire the economy by transitioning from  a ‘make, take, waste’ model to a circular economy where everything has a value and nothing goes to waste.  

We know that the climate and nature crisis is not just about carbon emissions. There are other impacts too – like biodiversity loss, rising pollution levels, and the depletion of natural resources, like water.

We need to look at all of these to enable a broader understanding of the environmental impacts of our waste and the overconsumption of raw materials. This is why we’ve developed the Scottish Waste Environmental Footprint Tool.

The Scottish Waste Enviornmental Footprint Tool (SWEFT) has been developed to provide a broader, measurable picture of the life cycle impacts of waste. This includes extraction, manufacturing, production, transport, recycling, and disposal.  

As with its predecessor, the Carbon Metric Publications, SWEFT includes the impacts of waste generated during the upstream production process, such as raw material extraction and manufacturing, and during waste management. Any benefits of waste treatment, for example due to recycling, are also included.

It is an evolution of the Carbon Metric, a pioneering development in the monitoring of waste impacts.  However, unlike the Carbon Metric, SWEFT expands our knowledge by expanding on the carbon impacts of waste to include the results of the  environmental damage indicators including: 

• Climate change (carbon emissions)
• Biodiversity loss
• Air pollution
• Water consumption
• Mineral resource scarcity
• Land use 

Food waste has the highest impact of any household waste on biodiversity loss and land use, as well as coming a close second to textile waste when it comes to climate change. 

The latest publication of SWEFT presents impacts from 2023, and historical analysis from 2018 – 2022. The waste types that contribute the most to climate change are textiles, food, plastic, paper, and Waste Electrical and Electronic Equipment (WEEE).  SWEFT figures show that when it comes to the impact of waste:  

• Food waste is the largest contributor to biodiversity loss.
• Textiles, WEEE, and food that we waste are the largest contributors to air pollution.
• Textiles and food waste contribute the most to water use impacts.  Tonnes of waste generated of these waste categories showed an increased trend during COVID-19 impacted years (i.e. 2020 and 2021) and therefore impacts in these years also increased.
• Food waste contributes almost three quarters of land use impacts.  
• WEEE dominates the impacts on mineral resource scarcity, meaning it is the biggest contributor to the depletion of metal resources.  The impact of COVID-19 on the collection of this waste stream at Household Waste Recycling Centres (HWRCs) can clearly be seen in the results for this impact category.    

To reach climate goals, such as net-zero, we should aim to reduce how much textiles, food, plastics, paper, and WEEE we waste. Recycling is a valuable step, but there is much more that can be done.  Realising the full potential of the circular economy and encouraging more reuse, sharing, and avoiding overconsumption will reduce how much we waste and reduce impacts more.