UK cold storage firm cuts energy bill by 20% with ammonia

UK-based cold storage firm Norish has cut energy bills by 20% at one of its distribution centres by switching from the HCFC R22 to the natural refrigerant ammonia.

Norish chose the ammonia plant, designed and built by J & E Hall and supported by three HallScrew compressors, for its long-term environmental credentials.

“Ammonia will be around for the foreseeable future,” said Norish Chief Engineer Stuart Lloyd. “It helps reduce our carbon footprint. Our job spec was for efficiency, reliability and economy of use.”

The R22 plant continued to run in the same area while the new ammonia plant was built, Lloyd explained. “We had to maintain temperature for the cold store while the new plant was being built. There were lots of crossover points. Halls handled those challenges beautifully,” he said.

J & E Hall also used variable speed compressor technology to optimise part-load efficiencies.

“The new ammonia plant operates with frequency inverters on both the condensers and compressors; this provides part-load efficiency gains and delivers accurate system control,” said Will Harrison, design and contracts manager at J & E Hall. “Norish had expressed a preference to operate the system to run at a positive pressure. This fitted with our philosophies of offering an efficient system running with low temperature differences.”