Researchers look to balance refrigeration demand

UK: An imitation supermarket at the University of Lincoln is being used to investigate demand side response (DSR) in refrigeration systems.

Funded by Innovate UK, the Refrigeration Research Centre (RRC) is the focus for new research by the University of Lincoln, IMS Evolve, Tesco Stores and The Grimsby Institute. Using cutting-edge technology to precisely model the dynamics of a typical supermarket, the researchers are exploring how to modify refrigeration control in proportion to the available energy on the National Grid while also optimising food temperature control.

Commercial refrigeration places significant pressure on the National Grid and represents up to one third of a typical retailer’s energy cost. The drive towards low carbon economies also means that the UK National Grid is becoming progressively more unstable, as renewable and decentralised energy sources such as wind and solar PV are less constant than traditional fuel sources. 

DSR aims to stabilise the grid by managing demand and using power more intelligently rather than simply generating more electricity to meet short periods of huge demand, and in turn growing the country’s carbon footprint. 

Working at the RRC as part of the two-year project, the researchers carried out a major industrial demonstration applying DSR to food retailing networks using IoT technology.

While recognising the importance of refrigeration, Professor Simon Pearson, director of the Lincoln Institute for Agri-food Technology, said: “Currently, control systems use very static control temperatures, but this project is developing algorithms to dynamically control refrigeration temperatures. 

“Successfully integrating food refrigeration systems into DSR mechanisms would have national and internationally relevant impact, and our research has shown that this can be done while controlling food quality and temperature control limits.”

Edward Porter, Director of IoT, IMS Evolve, commented: “Our pioneering retail refrigeration research alongside the University of Lincoln and Tesco has proven that it is possible to ensure the safety and optimise the quality of refrigerated produce whilst using demand side response. 

The new paper in Applied Energy reveals the results of testing different algorithms that control retail refrigeration systems in the event of a surge in demand which can’t be met by the National Grid.

The researchers from the Lincoln Institute for Agri-food Technology and the University of Lincoln’s School of Engineering established complex algorithms taking into account a number of key criteria, including estimation of the mass and thermal transfer rate of food in each refrigerator and numerical weather predictions. In addition the team worked with IoT specialists IMS Evolve to optimise the considerable IT architecture and data flows needed to handle the enormous data scale. 

“This project gave us a valuable insight into the safe boundaries of operations of our refrigeration systems,” said Tesco Stores energy manager Filippo Chiettini. “It allowed us to understand what degree of flexibility can be safely exploited for services like DSR. It also enriched our general understanding of how different types of food behave within different areas of a refrigerated cabinet.”

The new academic paper is available to read here.