The circular economy in refrigeration and air conditioning technology: current state of play in the UK

Sustainability challenges in refrigeration and air conditioning technology

Cooling systems such as refrigeration and air conditioning negatively impact the climate in two ways: through direct emissions from refrigerant leakage, and through indirect emissions from the energy used to power the system. Globally, indirect emissions account for as much as 60-80% of the climate impact, and in the UK alone, refrigerant use produces 10 megatonnes of CO2 emissions. Not only does more than 10% of Britain’s electricity go to cooling, but we spend around £5.2 billion each year on energy for cooling across the grid and transport.

Refrigeration systems in retail food outlets have been identified as a major culprit, with UK supermarkets lagging behind their European neighbours in the adoption of measures to reduce their energy consumption – changes which can be as simple as ensuring that doors are fitted to cabinets, which can reduce energy consumption by up to 40%. Additionally, refrigerated transport, which also forms a vital part of the so-called ‘cold chain’ to maintain perishable goods at a low temperature, has a significant impact on carbon emissions. Research carried out by Cenex on behalf of Transport for London revealed that diesel transport refrigeration units (TRUs) were particularly heavy polluters, as they can emit between three and 15 tonnes of tailpipe CO2 per year – the equivalent of between two and nine average UK cars.

However, the need for refrigeration and air conditioning technologies is firmly embedded in modern life, both in domestic and commercial settings. Indeed, climate change itself is creating a growing demand for air conditioning, resulting in a vicious circle whereby cooling systems are responsible for a high proportion of carbon emissions. So how can the industry best address this challenge?

How can we improve energy and resource efficiency?

One major driver for improvement is the UK government’s net zero growth plan. Based on the 2021 net zero strategy, which sets the ambitious goal of decarbonising the UK economy and reaching net zero by 2050, the government has produced a portfolio of research and innovation (R&I) investment of approximately £4.2 billion over the period from 2022-25. So, in addition to the ethical concerns involved, the availability of financial support provides an incentive to businesses to improve sustainability. A report on sustainable cooling by the Parliamentary Office of Science and Technology in 2021 noted there is relatively little specific policy for sustainable cooling in the UK. However, research suggests that in addition to reducing fluorinated gases (F-gases) and improving energy efficiency of devices, a greater focus on passive and behavioural strategies is needed. The report points to the concept of a ‘Cold Economy’, a system which uses waste and surplus cold as a way of storing and transporting energy for use in a range of applications other than cooling, in order to reduce environmental impact.

Specific measures to make cooling more sustainable cover both the technical and social aspects of the refrigeration and air conditioning industry. Technical aspects can include the adoption of lesser-used cooling technologies which result in lower greenhouse gas emissions: ‘reversible’ type heat pumps which also provide cooling by acting as air conditioning units; ground-source systems which circulate water through the ground to provide both heating and cooling; and recovery of waste cold to recycle energy.

Social aspects of sustainable cooling are mainly concerned with behaviour change, notably occupant interaction with buildings and equipment. Occupants’ familiarity with the best use of passive tools, such as opening windows and internal doors for cross-ventilation, is a key aspect of this, but cultural and social considerations need to be taken into account. While night-time ventilation is most effective for cooling, this may be unacceptable for reasons including security, noise and air pollution.
 

The circular economy: what is it and how can we achieve it?

The circular economy is an economic system based on the reuse and regeneration of materials and products in an environmentally friendly, sustainable fashion. It’s based on three principles: eliminating waste and pollution; circulating products and materials; and regenerating nature. The concept of the cold economy, referenced in the previously mentioned government report on sustainable cooling, is based on the circular economy model.

While infrastructure to support the circular economy is already in place for steel, aluminium and copper, recycling of electronics is more limited: in the UK only 17% of waste electrical and electronics equipment (WEEE) is formally collected and recycled. The Institute of Refrigeration has identified a number of key areas for moving towards a circular economy and put forward proposals including the introduction of capital allowances to increase the use of ‘second life’ products and components, financial incentives to support the purchase of such products, and policies to facilitate a UK-based comprehensive recycling infrastructure for all material types.

Clean cooling: examples of good practice

 Awareness of the circular economy in refrigeration and air conditioning may still have a long way to go, but there are some promising developments. Not only has UK Power committed to the circular energy transition, but significant projects in both the public and private sectors are reflecting the growing importance of clean cooling.

The National Health Service (NHS) is one of the world’s largest healthcare organisations. As air conditioning and refrigeration can account for over 25% of hospital carbon emissions, the NHS needed to act swiftly on government targets. Following four successful pilot schemes which reduced energy consumption by an average of 22% at UK hospitals, the NHS is now the world’s first healthcare organisation committed to net zero carbon.

In 2020, retail giant Sainsbury’s became the first UK supermarket to commit to meeting the government’s net zero targets by 2040. This includes fitting stores with aerofoil technology, keeping fridges cool and aisles warmer, and saving 15% of the energy used by the fridge. Sainsbury’s has pledged to make its fridges as efficient as possible through the use of innovative technology and increasing the use of natural refrigerants.