Brief: 12th c-dig meeting

Uusikaupunki in Finland was the setting for the 12 th c-dig meeting in April 2005 attended by 55 delegates. Roughly half the presentations were by Finnish companies, reflecting the tremendous focus on carbon dioxide in the region in recent years. Discussion focused on the recent installation in Zurich by Linde of a transcritical supermarket system - one which uses solely carbon dioxide. According to preliminary figures, the performance meets or exceeds traditional systems in all but the warmest weather conditions. The group visited the Kalaset Oy fish filleting plant. The compact system there cascades carbon dioxide with R-404A in one of the blast freezer chambers, and has given reliable performance throughout its first year of operation. Another visit was to the Vahterus ring - a 1000-m long indoor snow track for Nordic skiing. The novel design of the track which rises and falls by about 20 m would not have been possible with any other refrigerant, but the high gas density and flat temperature characteristics of carbon dioxide enabled 500-m circuits to be laid under the snow in small-bore copper tube. The next c-dig meeting will be held in September 2005, and will focus on transcritical systems. Further details, and information about c-dig membership can be found on the website at