A government agency has set a first by applying a ‘carbon’ factor to materials collected for recycling to prioritise those – such as textiles – with the biggest climate benefit.
Recycling performance has always been measured in terms of weight. In Scotland, that is about to change. Zero Waste Scotland has unveiled a ‘carbon metric’ to identify materials whose recycling will make the greatest contribution to the fight against climate change by delivering the greatest net greenhouse gas (GHG) emission savings while offering valuable savings on primary resources.
In practice, this means prioritising recycling of textile, food and plastic waste over paper, for example. The carbon metric is based upon lifecycle thinking. It calculates emissions saved from recovering and using secondary resources from the waste stream instead of primary alternatives. This takes into account CO2-equivalent emissions from extracting a raw material and manufacture, all the way through to transport, distribution and recovery/disposal.
A comparison between aggregate and textiles illustrates what is at stake. Aggregate is very heavy – contributing much to a weight-based target – but its extraction and use cause relatively few emissions. In contrast, textiles are light but energy intensive to produce. Materials with a high carbon impact such as textiles and plastics are currently little recycled in Scotland.
To decide where to focus recycling efforts also depends on the relative proportions of materials in a waste stream. Unlike textiles, food and drink waste does not come with a heavy carbon footprint, but there is a lot of it. A recent report by WRAP and WWF found that food and drink waste – some 570 000 tonnes a year – represent around 3% of Scotland’s domestic GHG emissions, equivalent to those created by 600 000 cars annually.
The Scottish Government intends to use its new metric to assess recycling performance for all sources of waste: household, commercial, industrial, construction and demolition. The metric will be first applied to municipal waste, the only stream for which comprehensive data is currently available.
Scotland’s target for 70% recycling by 2025 will be refigured to take into account the new metric. UK and EU reporting will remain weight based however, and related targets will still need to be met, the Scottish Government emphasises. The revised EU Waste Framework Directive requires Member States to recycle, by 2020, 50% by weight of paper, metal, plastic and glass from households, and 70% of construction and demolition waste.
The carbon metric will be reviewed regularly to take into account developments enabling greater recovery of certain materials. Already, the metric gives a higher weighting for glass recycled back into glass rather than turned into aggregates or insulation, for example.
‘Scotland launches world-leading approach to measuring recycling performance’ (Zero Waste Scotland press release)
‘New report highlights water and carbon impact of wasted food’ (WRAP press release)
Carbon metric guidance document:
http://www.scotland.gov.uk/Resource/Doc/345031/0114810.pdf [516 KB]
Revised 2008 EU waste framework directive:
http://eur-lex.europa.eu/LexUriServ/LexUriServ.do?uri=OJ:L:2008:312:0003:0030:*:PDF [146 KB]