The Chill Hunters

There's a dirty secret around the back of your fridge. The world's freezers, fridges and air conditioning units are chilled by gases that have planet-warming properties that are hundreds or even thousands of times more powerful than carbon dioxide. Disposed of properly they're not a problem but in much of the developing world these gases - legal ones and even more dangerous illegal gases - are simply vented to the atmosphere when the cooling units are dumped or recycled.

In this episode of 39 ways to save the planet, Tom Heap meets the fridge detectives hunting the planet for the worst offenders and safely disposing of their deadly gases.

Dr Tamsin Edwards of King's College, London, armed with statistics gathered by the Society, joins Tom to add up the numbers and calculate the carbon impact of the fridge detectives.

Listen now on BBC Radio 4

What our experts say

We asked Society Fellows Dr Luke Western and Dr Daniel Say from the University of Bristol, and Professor John Pyle from the University of Cambridge to offer some observations on the potential of intercepting and destroying refrigerant gases in reducing carbon emissions. Their points take some of the themes of the programme a step further.

Dr Luke Western and Dr Daniel Say

Based on the 2018 Scientific Assessment on Ozone Depletion, carbon dioxide equivalent (CO2e) chlorofluorocarbon (CFC) emissions peaked in the late 80s at roughly 10 Gigatonnes per year (Gt/yr). The introduction of the Montreal Protocol led to a rapid decline in emissions of CFCs and chlorinated solvents, resulting in a steady decrease in CO2E emissions, falling to ~3 Gt/yr in 2005. However, in recent years global emissions of hydrofluorocarbons (HFCs) have risen rapidly, offsetting some of the gains made via the phase-out of CFCs. We expect global HFC emissions to continue to grow over the next decade (predominantly due to demand in developing countries), and hence total CO2e to increase.

Some countries have national legislation which ensures that all CFC/Hydrochlorofluorocarbons (HCFCs) in fridges are destroyed (like the UK). It is very difficult to enforce the legislation, and if an individual chooses to dispose of a refrigerator illegally, there is little that can be done.

CFC emissions are now around 1 Gt/yr (CO2e), and we can assume that the vast majority of these emissions are from the banks. The bank of major CFCs (CFC-11, CFC-12 and CFC-113) has been estimated to be 13 Gt, released at approximately 4%/yr. We can speculate that just around 5 Gt of these CFCs are in fridges and air conditioning units (RAC). Therefore, if we could destroy all CFCs still contained in RAC units, we could prevent approximately 5 Gt CO2e of potential emissions (similar to USA’s fossil fuel CO2). Note that this is if we destroyed it all now – in reality, the banks continue to leak, reducing the quantity of CFC available to be destroyed.

HCFCs are a more complicated picture as their production and consumption is still ongoing. Developed countries can only manufacture HCFCs for non-emissive uses, such as feedstock use (HCFC-22 is used in the manufacture of Teflon). Developing countries can still produce HCFCs for emissive uses, though they must phase-out any ongoing production by 2030. Currently their emissions are similar to CFCs in terms of CO2e.

The Kigali Amendment to the Montreal Protocol (i.e. phase out of HFCs for hydrofluoroolefin (HFOs)) has now been ratified by 114 countries (not China & USA). The Kigali Amendment is no longer about ozone, as HFCs do not destroy the ozone, it is purely about climate impact.

What are the limiting factors?

Dr Daniel Say and Dr Luke Western

Some HCFCs/CFCs are produced in small quantities as a by-product of other industrial processes, reinforcing the fact that this is something that is very difficult to police. 

Dr Daniel Say

HCFCs will not be phased-out globally until 2030, so stocks continue to accumulate.

It can be difficult to locate and transport gases from remote communities, some may never be discovered or intercepted. Policing is very difficult and political instability makes the process challenging.

If resources are limited, it would make sense to focus on gases/sectors with the highest ozone-depletion potentials (ODPs) and/or global warming potentials (GWPs). For instance, targeting a single CFC filled fridge would have the same impact as disposing of many aerosol canisters filled with HFC-152a (which has a much lower GWP).

Dr Luke Western

There will still be small CO2 emissions when the refrigerants are destroyed (but much less than their CO2e, likely a few percent).

Professor John Pyle

Illegal production

The Environmental Investigation Agency report, is a useful resource regarding illegal production and use of banned CFC-11 in China’s Foam Blowing Industry.

There has been a lot of work on ’banks’ of ozone depleting substances (ODSs); if we do not know the banks well enough, we will not know how much might leak out into the atmosphere.

What are the co-benefits of managing refrigerant gases effectively?

Dr Daniel Say

Managing refrigerant gases effectively would help protect the ozone layer and recovery of the Antarctic ozone hole. Recycling of these gases on a large scale could reduce demand for new (virgin) refrigerant, which has additional benefits. For instance, the manufacture of refrigerant HCFC-22 generates fluoroform (HFC-23) as an unavoidable by-product, which is itself a highly potent greenhouse gas that is often vented to the atmosphere.

Dr Luke Western

It is quite hard to disentangle emissions from the bank from ‘prompt’ (consumption/production-related) emissions. Therefore, if we reduce the emissions from the bank it will be much easier to spot any violation of the Montreal Protocol.

It could potentially encourage recycling of the fridges themselves, rather than them being put into landfill. However, the chemical may be destroyed and then casing dumped.

Are there any potential negative impacts of this idea?

Dr Daniel Say

Scale is the biggest challenge. To make a significant dent in the existing banks, tens of millions of units would need to be processed. The transport of millions of RAC units will itself have a large carbon footprint, and this needs to be compared with venting/disposal of the unit locally.

Dr Luke Western

Bringing in legislation to ensure fridges are disposed of properly will be costly, and disproportionally impact poorer communities. The Multilateral Fund currently compensates countries when implementing production phasedowns, so it’s possible that a similar framework could work for disposal.

Further reading

• Engel, A. and Rigby, M. et al. (2018), Scientific Assessment on Ozone depletion, Chapter 1. NOAA Chemical Sciences Laboratory

• Park, S., Western, L.M., Saito, T. et al. (2021), A decline in emissions of CFC-11 and related chemicals from eastern China. Nature 590, 433–437

• Rigby, M., Park, S., Saito, T. et al. (2019), Increase in CFC-11 emissions from eastern China based on atmospheric observations. Nature 569, 546–550

• Stanley, K.M., Say, D., Mühle, J. et al. (2020), Increase in global emissions of HFC-23 despite near-total expected reductions. Nature Communications, 11, 397

• The Economist (2014), Curbing climate change: the deepest cuts.

• UK Gov (2002), The Environmental Protection (Controls on Ozone-Depleting Substances) Regulations, Crown copyright

   

About the series

39 ways to save the planet is a new radio series by BBC Radio 4 developed in partnership with the Society and broadcast in 2021. It showcases 39 ideas to relieve the stress that climate change is placing on the Earth. In each 15 minute episode Tom Heap and Dr Tamsin Edwards meet the people behind a fresh and fascinating idea to cut the carbon.

Programme website

Over the course of 2021, the Society will be producing events and digital content to accompany the series.