UK team to design sustainable clean cold technologies

University of Birmingham

A new, more sustainable, way of delivering refrigeration and cold storage using carbon dioxide is being developed in a programme led by researchers at the University of Birmingham.

The team, which also includes researchers from Heriot-Watt University and the University of Glasgow, have been awarded £1.2M from the Engineering and Physical Sciences Research Council to design the system. The researchers anticipate the technology will make a significant contribution to UK’s efforts to reach the net-zero emission target in 2050.

The system will use CO2 hydrate – a crystalline structure formed by mixing CO2 and water under pressure. This material can be use both as a refrigerant and as a way of storing cold, so it can be produced at off-peak times and also by using renewable sources of energy, before being used as required.

Cold air and refrigeration is vital in modern society, but consumes up to 14 per cent of the UK’s electricity and is also responsible for around 10 per cent of the UK’s greenhouse gas emissions. These emissions include the CO2 from power consumption, but also the leakage of refrigerants – and both of these make a significant contribution to global warming.

Current methods of storing cold rely on chilled water storage, but this is typically only used on very large projects. Ice storage is another option, but while ice is more compact, it requires more chiller energy.

By using this new technology to store cold effectively, the researchers predict the UK could achieve a decrease of 40-50% in peak period fuel consumption for cooling.

Dr Yongliang Li, of the Birmingham Energy Institute, is leading the research. He says: “This approach will reduce our reliance on fossil fuels for producing cold and will help the UK lead the way in adopting a healthier, more sustainable energy system.

Working closely with industry, a key aim for the team is to design a system that will be straightforward to adopt for companies that rely on refrigeration. The system will enable companies to adopt new, sustainable technologies, while also improving their competitiveness.