UK: Waitrose installs HFO chillers in store

Waitrose, the English supermarket chain, is testing chillers using HFO-1234ze refrigerant at its supermarket in Bromley, near London, UK.
Waitrose, the English supermarket chain, is testing chillers using HFO-1234ze refrigerant at its supermarket in Bromley, near London, UK.
Believed to be the world's first supermarket installation of a packaged HFO chiller, the system uses two 180 kW Geoclima chillers with Frascold semi-hermetic reciprocating compressors providing chilled water as a condensing medium for the in-store integral cases using R1270 (propene) as a refrigerant. Although measured over a relatively short period of time, initial comparison with a same-size store in Canterbury running identical systems, but using R290 (propane), is said to have shown a 20% reduction in energy consumption.
If the trial is successful, Waitrose plans to adopt the HFO solution as part of its refrigeration platform for future stores, along with the continued use of hydrocarbons and tri-generation where appropriate.
Tests carried out by Frascold with 8-cylinder reciprocating compressors running on R1234ze indicate a loss of capacity of around 24% compared with R134a across various application conditions. However, the mean power absorbed is almost 27% less, and the overall COP is in fact better than R134a across a range of applications and conditions. Frascold's research and development team believe that performance with HFOs can be significantly improved with further optimization.