Natural refrigeration technology is gaining traction with end-users, according to speakers at the Atmosphere Conference in Brussels last month
Furthermore, it was revelaed that despite technological successes, there are still challenges to overcome in the form of regulatory obstacles and skill shortages.
Supermarket end-users reported a key development, with the first successful year’s operation of transcritical carbon dioxide refrigeration systems in warmer climates. Ambient temperatures above 20 deg C, previously considered unfeasible for transcritical CO2, now appear to be not only achievable but cost-effective, thanks to recently developed parallel compression and ejector technology.
Major European retailer Carrefour is spearheading the drive with trial stores in Spain. Asset manager Jean-Michel Fleury reported that the trial store in Valencia, which has now been running a transcritical system for 15 months, is showing an astounding return on investment of 1.2 years.
The store, which uses a range of energy-saving technologies to augment the transcritical system, has posted operational energy savings of 47 per cent over like-for-like conventional technology. Even without the extra elements – such as glass doors and LED lighting – the net saving is still 13 per cent from the refrigeration system, Mr Fleury reported.
But arguably more impressive than the energy saving is the proposed cost saving: Carrefour estimates that Alzira will save €792,000 over a ten-year period, despite an increased capital expenditure for the equipment of €94,000.
Its Alzira store uses so-called parallel compression technology, which overcomes the inefficiencies associated with carbon dioxide in warmer ambients.
But Mr Fleury said that another trial store in the region, at Castellon, which uses proprietary ejector technology as well as parallel compression, is expected to provide additional energy savings over the Alzira store.
Gabriel Romero of the Auchan group also reported successful operation of a transcritical booster system in the retailer’s Simply supermarket in Bilbao, Spain. Operating since last July in ambients of 19 to 20 deg C, the system’s energy performance has so far been similar or better to conventional systems, he said.
Mr Romero said that the cost of components and the lack of skilled maintenance engineers remained serious obstacles to progress.
Mr Fleury called on national associations, governments and the supply chain to encourage appropriate training of the installers, and he urged suppliers and installers to invest the time and technology into improving the installations for warmer climates.
Michel de Rooj of the Ahold group added that the next challenges for his group were to find the appropriate natural refrigerant solution for small-store footprints and for AC systems.
There was more encouraging news from the Belgian market though, where Georgios Patkos of the Delhaize group reported that the price gap was narrowing between natural components and the norm. The cost of installing a CO2 transcritical booster system is now just 4 per cent higher than an efficient HFC system running R407F, he said.
The supermarkets were of a consensus that finding a standard natural solution for the HVAC system was more of a challenge.
Regulations limiting charge size and use of flammables in buildings are restricting use of hydrocarbons in some countries, and there have been calls for the EC to make more concessions to hydrocarbons in its regulatory framework.
Supermarket managers were agreed that harnessing waste refrigeration heat and using absorption or adsorption chillers was one way of providing HVAC from the transcritical systems.
The scale of the task facing those who have to comply with the F-Gas regulations in Europe was demonstrated by Olaf Shulze of German retail chain Metro. Mr Shulze outlined a ten-year programme of 483 European store upgrades as part of its F-Gas exit plan – a programme that will cost more than €1 billion. But as an indication of how CO2 technology is being exported around the world, he reported that among the upgrades planned this year are installations in Metro stores in China and Russia.