WINTER AIR AS A SOURCE FOR COLD STORAGE INJECTION

• Main Authors: Bo Nordell, Derya Dikici
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Utes; Luleå
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.569.7236

There is an increasing interest in Low Temperature Underground Thermal Energy Storage (LT UTES) for the purpose of space cooling. Some of the different types of UTES systems, with an anti-freeze heat carrier in a closed pipe system, tolerate injection temperatures below freezing. Thus, seasonal storage of cold with injection temperatures below freezing would be possible in large Borehole Thermal Energy Stores (BTES). The most obvious cold source is the cold winter air. There is however very little experience of low temperature cold extrac-tion from air for injection into the ground. A low temperature cold injection field test was performed during the winter of 1997/98 at Luleå University of Technology. The test was performed in one 65 m b rehole drilled verti-cally into the crystalline bedrock. Cold was extracted from the winter air at occurring air temperatures- i.e. sometimes well below-30oC. The aim of this test was to obtain experience of problems associated with cold extraction from the air and cold injection into the ground. 1.