27/09/2012
I was interested to read about Mayekawa’s (http://www.mayekawa.com.au/products/pascal-air/ ) use of compressed air for cooling in Ecolibriums September issue (p62).
I recall experimenting with expanded compressed air to provide cooling in my uni days and have always wondered if it could be efficiently and commercially applied. Mayekawa is of course using air in a closed system to achieve very low space temperatures (-100 deg C). Perhaps it is the low temperature application that makes it an efficient system.
My thoughts were to distribute compressed air at a rate equivalent to the minimum outside air requirements and then expand it through microturbines located per floor or even per desk in order to cool it. Heat from a compressor after cooler could be used to generate chiller water through an absorption chiller to supply supplementary passive cooling such as chilled beams and electrical energy generated from the microturbines could be collected and fed back to the compressor improving efficiency.
Of course there would be lots of issues to address including noise but imagine the flexibility and space saving of a ductless AC system.
On another thought I wonder if they could tune down their Pascal-air system to compete with a refrigeration chiller??
Perhaps one day I’ll get a chance to look at the efficiency and economics of these applications.
As for innovative approaches congratulations Mayekawa and hopefully our industry will embrace such existing and future alternatives.
The air we breathe is used as the ‘refrigerant’ in this case, using a unique internal compressor-expander turbine, Pascal Air produces cold air which is simply ducted to the refrigeration space.
