This work benchmarks the existing UK cold chain and provides robust evidence-based data on emissions in 2020. Only emissions from refrigeration within UK borders was considered, both from refrigerant leakage and from electrical power usage. Energy consumption For energy consumption the Digest of UK Energy Statistics (DUKES) was widely used. This data is compiled by the Department for Business, Energy & Industrial Strategy (BEIS) and contains data for many years up until the current year. The United Kingdom Statistics Authority has designated these statistics as National Statistics, in accordance with the Statistics and Registration Service Act 2007 and therefore they were considered as the most accurate data available. DUKES data does not always differentiate the energy consumed by refrigeration systems in each of the cold chain sectors and therefore further analysis and assumptions were often required. Energy consumption values shown were collated per year for the years 2019/2020, unless otherwise stated. Emissions from refrigerant leakage The main GHG refrigerants are the fluorinated gases (f-gases); hydrofluorocarbons (HFCs) and hydrochlorofluorocarbons (HCFCs). According to Brown et al (Brown et al., 2021) emissions of f-gases can occur at various stages of the refrigeration equipment life-cycle: • During manufacturing • During installation • Over the operational lifetime • At disposal. The most comprehensive source of information for direct emissions is the UK Greenhouse Gas Inventory. This contains national greenhouse gas emission estimates for the period 1990-2019 and is the United Kingdom’s National Inventory Report (NIR) submitted to the United Nations Framework Convention on Climate Change (UNFCCC). It includes losses during manufacture/initial charging and at decommissioning as well as losses in use.The UK energy system is changing rapidly. Greenhouse gas emissions fell by 43% between 1990 and 2017, and renewables now account for 30% of electricity generation. Despite this progress, achieving emissions reductions has been difficult outside the electricity sector, and progress could stall without more effective policy action. The Paris Agreement means that the UK may have to go further than current targets, to achieve a net zero energy system. Reducing emissions is not the only important energy policy goal. Further, progress need to be made whilst minimising the costs to consumers and taxpayers; maintaining high levels of energy security; and maximising economic, environmental and social benefits. There is a clear need for research to understand the nature of the technical, economic, political, environmental and societal dynamics affecting the energy system - including the local, national and international components of these dynamics. This proposal sets out UKERC's plans for a 4th phase of research and engagement (2019-2024) that addresses this challenge. It includes a programme of interdisciplinary research on sustainable future energy systems. This is driven by real-world energy challenges whilst exploring new questions, methods and agendas. It also explains how UKERC's central activities will be developed further, including new capabilities to support energy researchers and decision-makers. The UKERC phase 4 research programme will focus on new challenges and opportunities for implementing the energy transition, and will be concerned with the three main questions: - How will global, national and local developments influence the shape and pace of the UK's transition towards a low carbon energy system? - What are the potential economic, political, social and environmental costs and benefits of energy system change, and how can they be distributed equitably? - Which actors could take the lead in implementing the next stage of the UK's energy transition, and what are the implications for policy and governance? To address these questions, the research programme includes seven interrelated research themes: UK energy in a global context; Local and regional energy systems; Energy, environment, and landscape; Energy infrastructure transitions; Energy for mobility; Energy systems for heat; and Industrial decarbonisation. The proposal sets out details of research within these themes, plans for associated PhD studentships and details of the flexible research fund that will be used to commission additional research projects, scoping studies and to support integration. A first integration project on energy and the economy will be undertaken at the start of UKERC phase 4. The research themes are complemented by four national capabilities that form part of the research programme: an expanded Technology and Policy Assessment (TPA) capability; a new Energy Modelling Hub; the UKERC Energy Data Centre; and a new Public Engagement Observatory. Research within TPA and the Observatory will align and integrate with the main research themes. These four capabilities will also enhance UKERC's ability to provide evidence, data and expertise for academic, policy, industry and other stakeholder communities. The UKERC headquarters (HQ) team will support the management and co-ordination of the research programme; and will also undertake a range of other functions to support the broader UK energy research community and its key stakeholders. These functions include promoting networking and engagement between stakeholders in academia, policy, industry and third sector (including through a networking fund), supporting career development and capacity building, and enhancing international collaboration (including through the UK's participation in the European Energy Research Alliance).

The cold chain was split into sectors. These were: • Agriculture • Food and drink production • Cold storage (after production) • Retail • Food service • Transport between all sectors • Domestic GHG emissions were split into direct emissions from refrigerants and indirect emissions from the electricity consumed. As emissions from refrigerated transport units (TRUs) originate from the diesel engines that power the TRUs, these have been included in the energy consumption section, to separate them from the emissions from the refrigerants. For all sectors except transport the indirect emissions from energy consumption were converted into GHG emissions based on the carbon intensity of the grid in 2019 of 0.22 kgCO2e/kWh (BEIS, 2021). For transport, electricity is rarely used for the refrigeration, as refrigeration systems on vehicles are almost always driven directly from fossil fuels. Only the emissions associated with the refrigeration of the vehicle were considered and emissions to drive the vehicle were excluded. A literature review of reports and peer reviewed papers was conducted with the aim of finding the latest and most comprehensive data on emissions. A level of confidence was attached to the results which considered the quality of data, agreement between separate sources and age of the data.