Freshcold managing director John Haffenden brings an engineer’s eye to all the company’s projects and is particularly keen to find ways to install more efficient systems.
It was his knowledge of the science behind refrigeration – and his commitment to the environment and lower running costs – that led him to invent a system that automatically defrosts cold store chillers using stored ‘free’ heat.
John’s invention – unique in the UK – involves storing waste heat that has been produced by the cooling process and is normally lost to the outside air.
That waste heat is then released automatically when it is needed and used to defrost the chillers, saving money and reusing energy that would otherwise be wasted.
“In situations where chillers need defrosting, the system can save 34 kw of electricity per day in a 100 tonne fruit store,” John explained. “When you are storing fruit at below two degrees, the chillers can need defrosting up to four times a day, in which case using free heat makes good economic sense.”
John came up with the idea of reusing heat in this way while working with his former company, Farm Refrigeration, but it was not until 2011 that he was able to trial the system.
“I was fitting out new cold stores for Peter Chandler of Chandler & Dunn, just outside Canterbury, and asked if he would allow me to trial the new system in three of the units,” John explained.
“He was happy to host the trial and in the event it worked so well that he insisted I return a year later to add the defrost system in seven other stores,” he went on.
“Energy efficiency is one of our big drivers at Freshcold and when you have 100% free heat to play with it makes sense to put it to good use. It paid off for Chandler and Dunn, and other customers have benefited from the technology since then.”