October 22nd, 2018

Target practice: should recycling targets be weight or carbon-based?

6 minute read

by Peter Jones


As the prospect of higher weight-based recycling targets emanating from Europe has moved from a distant possibility to an imminent reality, interest in alternatives to such targets seems to have grown.

Environment minister Therese Coffey has repeatedly said that she favours “resource-efficiency” focused targets over weight-based targets. More recently the ESA has called for the adoption of a mixture of metrics, including carbon-based targets, for different waste streams. Why?

The most widely quoted rationale for a focus on carbon is to avoid perverse incentives. Weight-based targets, it is said, lead waste collectors to focus on heavy materials that, when recycled, don’t yield very large carbon benefits – garden waste and glass being prime examples.


The garden waste of England

Certainly, some authorities recycle a lot of garden waste. Statistics published by Defra show that in 2016/17, the council with the largest share of garden waste in its household recycling was Tonbridge and Malling: 15,498 tonnes of green waste (71.6%), compared with 6,155 tonnes of dry recycling. Green waste made up 30.4 percentage points of their household recycling rate: this was exceeded by Rochford Council, (37.9 percentage points), but better dry recycling performance meant that garden waste was a smaller share of Rochford’s recycling overall.

However, these are outliers, which can similarly be found at the other end of the scale. Across England, garden waste contributes a more modest 18 percentage points to the household recycling rate. While that’s undoubtedly a lot of garden waste, contributing more than a third of England’s 43.7% household recycling rate for 2016/17, does it indicate a perverse incentive at work?

I’m not sure that it does. For one thing, while the UK is aiming to reach a 50% recycling rate by 2020, the Government hasn’t actually set binding, weight-based targets for English local authorities as a means to achieve this. Their recycling practices result mainly from Landfill Tax pushing up the cost of disposal – and from the separate collection requirements of the Environmental Protection Act 1990 and Waste (England and Wales) Regulations 2011. Diverting material into reuse and recycling is a response to an economic imperative – a weight-based economic incentive, which charges for disposal on a “per tonne” basis – which would be expected to apply regardless of how any targets are set.

Further, the balance of economic incentives is currently leading authorities to switch to charged-for garden waste collections. This leads to a reduction in the number of households that use the scheme, and therefore some reduction in yields. So, as things stand, there is no target driving councils to collect garden waste, and as we get closer to the 2020 target date, councils are adopting measures that will decrease the amount of garden waste they collect.


Aiming high

What would happen if English local authorities were to be set weight-based targets? Would perverse incentives then start to kick in? We can look to Wales as a case study, as councils there already have high, binding targets.

There, we see a lot of evidence of increases in recycling performance, and not much indication of widespread gaming of the system through garden waste. Welsh Government statistics show that out of around 1.3m tonnes of household waste collected in 2017/18 only 167,000 tonnes was garden (or mixed food and garden) collected for composting. That means garden waste contributed only 12.6 percentage points to Wales’s rather higher overall household recycling rate.



Green shoots: do weight-based recycling targets result in perverse outcomes? Photo: Justin Ladia (CC BY 2.0), via Flickr.


So, Wales – where councils have weight-based targets – derives less of its recycling rate from garden waste than England – where there are no such targets. Not too much indication of a perverse incentive there, then.

Even if weight-based targets don’t have especially perverse outcomes, they do have flaws. For example, weight-based recycling targets give little incentive to reduce waste: so long as you recycle a lot of material, it doesn’t matter how much waste is managed in total – though of course one could set separate, weight-based residual waste targets. It’s also difficult to make fair recycling rate comparisons between urban and others areas when garden waste makes such a big contribution outside the cities.

Carbon-based performance measures can be made more sophisticated. The London Environmental Performance Standard, for example, sets a target based on tonnes CO2 per tonne of waste managed, encompassing residual waste, recycling and reuse. One can imagine a further refinement where one looked to assess the embodied carbon of all household waste and deduct the carbon benefits resulting from recycling and other waste management processes to yield a figure for residual carbon emissions from waste per household.

This would give a much stronger sense of the total impacts from waste from each area, in a way that allows much clearer comparisons between different parts of the country. But would it be a good way to set a target?


A large target

It’s important to distinguish between carbon-based targets and carbon metrics. A metric is typically a means of informing of measuring outcomes to improve policy. Take the Scottish Carbon Metric, for example, which Eunomia has adapted to produce a Recycling Carbon Index for the rest of the UK. This quantifies the greenhouse gas emissions savings from local authority recycling. The Scottish Government uses the metric to inform policy and to communicate the benefits of recycling, but not to set targets for local authorities to achieve.

As targets to drive local authorities’ recycling practices, carbon-based metrics might be problematic. One issue is that a fair target needs to relate to something over which the council has a fair degree of influence:

  • Any carbon metric relies on a set of carbon footprints for materials. These are complex to calculate and need to be updated regularly. Scotland updates the carbon metric every two years to take account of variables such as “New technologies, more efficient processes and the growth of renewable energy”. Sometimes the environmental benefits of recycling a particular material change significantly. If a carbon metric was used as a target, the effect of such an update could be to alter councils’ apparent performance in a way that is unrelated to any change in their behaviour – confusing for officers and local residents alike.
  • As metrics become more sophisticated, they tend to become further removed from a local authority’s ability to influence performance. A carbon metric might highlight, for example, that an area that produces little waste per household performs better than an area with a higher recycling rate on a larger arisings figure. But while councils have some ability to drive waste prevention, this is quite limited. What action could they take to improve their performance?


Perhaps the greatest attraction of carbon-based targets is that they tend to focus attention on the material that yields the greatest carbon savings per tonne – aluminium and textiles being particularly strong examples. However, this also makes them insensitive to materials that are important for reasons other than their CO2 impacts. Recycling waste electronic and electrical equipment doesn’t yield major CO2 savings, but does recover valuable and potentially hazardous materials.

Equally importantly, at a local level, “focusing” has the most impact when targets aren’t too challenging. As they reach higher levels, then – whether carbon or weight based – the actions councils need to take to meet them are much the same: a comprehensive recycling system backed by good communications. And while there may be no such thing as a perfect local authority recycling target, any set of incentives that makes sure councils put such systems in place has arguably done its job.


Peter Jones



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