The CO2 market in Bulgaria is complex in that it is directly influenced by the biggest foreign-owned retail food chains: Kaufland, Metro, Lidl and Billa. Kaulfland operates 1,000 stores in Germany, the Czech Republic, Slovakia, Poland, Romania and Croatia and is working with Carrier in Bulgaria.
Along with Lidl, Kaufland is investigating transcritical CO2 solutions but currently there are only cascade systems installed in Bulgaria, with its hotter climate a minor barrier to overcome.
Facility Manager Expert at Kaufland in Germany, Andreas Koch, said the company was looking into transcritical technology and explained the landscape in Bulgaria.
“We are currently conducting system tests, for the countries in which Kaufland is active, to determine to what extent a CO2-only system can be best realised. Romania and Bulgaria are included,” he said.
“The refrigeration systems are indeed negotiated centrally, but system design, installation planning, and execution is always carried out with the refrigeration company in the country (of installation) in coordination with the central refrigeration company.”
Kaufland’s KKV hybrid system has been adopted in the retailer’s past 12 stores and uses CO2 for low temperature and R134a on the medium temperature side. The chiller heats, cools and air conditions with 100% of the waste heat from the system recovered and used. A heat pump steps in when the reused waste heat is not sufficient.
Kaufland delivered the first of these cascade systems in 2013 following its first store opening in 2006. Kaufland is planning five further cascade projects in Bulgaria and has ‘adopted very innovative and environmentally friendly heating, cooling and refrigeration technology in the last 12 stores’.
Retailer project profile in Bulgaria
- Kaufland: Working mostly with Carrier, the only major supplier with a branch office in Bulgaria (Sofia), Kaufland will soon have 50 stores in Bulgaria with the last 12 adopting CO2/R134a cascade refrigeration (KKV) systems.
- Metro Cash & Carry: Metro has 11 Cash & Carry and two compact stores in Bulgaria. Recently, two stores were remodeled with the refrigeration system upgraded to a cascade CO2/R134a system.
- Lidl: Lidl’s logistics centre in Sofia as one of the country’s ‘most innovative’. The NH3/CO2 cascade system pumps liquid CO2 from the receiver to the air coolers and utilises CO2 evaporators in the deep freezer rooms.
- Carrefour: Although Carrefour is pushing innovation boundaries in Romania the Bulgarian arm is owned by a Greek subsidiary and as such has a vastly different in store policy. Carrefour has a high volume of stores in Bulgaria but all their installations use R404a as the refrigerant.
Lessons from Romania
In 2013, neighbouring Romania installed its first CO2 transcritical system, in a Carrefour store in Gelati. Advansor supplied the system, which uses parallel compression to increase system efficiency at the higher ambient temperatures, with the company’s Commercial Product Manager Torben Hansen confirming the project had been a great success.
Given the Gelati store’s purported 30% energy savings, four more projects were commissioned for Carrefour hyperstores in Romania as of November 2014, using parallel compression and an external hydrocarbon subcooler.
Razvan Voicu, Operation Manager at Frogotechnica Srl., who were involved in installing Romania’s first CO2 transcritical project in Gelati, explained the importance of additional technology for ensuring efficiency in high ambient temperatures.
“We have experienced how important parallel compression and gas subcooling is for our region. The Bucharest-Vulcan project relies on subcooling, without which the plant works in very high load conditions. As soon as the chiller is working we can observe a clear difference and improvement in operation,” he said.
Firmer legislation will eventually guide Bulgaria down the right path with Romania acting as proof that Eastern European countries can adopt low global warming potential technology.
Koch said the degree to which Bulgaria sees ‘greater independence in the country’ depends largely on the cooling companies available domestically.
“In Romania, for example, (Kaufland) worked directly with a local cold partner, whether this will be the case in Bulgaria in the future, we can’t say at this time,” he said.