imprint EDITORIAL PUBLISHER Alexander Büchler, Managing Director HEAD OFFICE heidelberg business media GmbH Hubweg 15 74939 Zuzenhausen, Germany phone: +49 6221-65108-0 fax: +49 6221-65108-28 [email protected] EDITORIAL Kay Barton Heike Fischer Gabriele Kosmehl Michael Maruschke Ruari McCallion Anthony Withers WikiPETia. info [email protected] MEDIA CONSULTANTS Martina Hirschmann [email protected] Johann Lange-Brock [email protected] phone: +49 6221-65108-0 fax: +49 6221-65108-28 LAYOUT AND PREPRESS EXPRIM Werbeagentur | exprim.de Matthias Gaumann READER SERVICES [email protected] PRINT Chroma Druck Eine Unternehmung der Limberg-Druck GmbH Danziger Platz 6 67059 Ludwigshafen, Germany WWW www.hbmedia.net | www.petpla.net PETplanet Insider ISSN 1438-9459 is published 10 times a year. This publication is sent to qualified subscribers (1-year subscription 149 EUR, 2-year subscription 289 EUR, Young professionals’ subscription 99 EUR. Magazines will be dispatched to you by airmail). Not to be reproduced in any form without permission from the publisher. Note: The fact that product names may not be identified as trademarks is not an indication that such names are not registered trademarks. 3 PETplanet Insider Vol. 24 No. 07+08/23 www.petpla.net Dear readers sweltering in the summer heat, Here I am, sitting in front of my computer penning this editorial and the mercury is almost hitting 40 °C. Who wants to sit next to an unhealthy air conditioner? But there are other ways of keeping cool indoors. Some have suggested placing a freezing PET bottle filled with water on the refrigerator. Naturally this piqued my interest. Could this be the answer – one bottle for one room? Let us look at the problem theoretically. I will spare you a lecture on thermodynamics but it is well known that 1m3 of air releases 1.2 kj (kilojoules) to cool by 1 kelvin, provided, of course, that pressure remains constant. On the other hand, 1 litre of ice requires 40 kj to go from -20° to 0°. In addition, the melting energy during the transition phase from solid to liquid is 334 kj. So, in a room of 60m3 (2.5m x 4m x 6m) we could, with a bottle of water on the fridge, reduce the air temperature by five kelvins. This should make us sit up and take notice – in theory at any rate. In practice, however, the reduction in temperature does not occur straight away but is a longer process during which cool air is transferred to walls and furnishings and its cooling effect is therefore dissipated. So, apart from a nice pool of water condensation under the bottle, nothing happens. However, as a brewer (regular readers will be well aware of my beer activities), I put the beer in PET water bottles in the freezer. Water in beer freezes at 0 °C, and alcohol at -100 °C. In the evening, I take out the freezing PET bottle, open it and turn it upside down. Only the alcohol comes out, carrying with it a concentrated taste of beer. The ice stays in the bottle. And now I have a room cooler that doesn’t work but a delicious Eisbock in my hand. I’ll give you two guesses as to which one I prefer! Cheers. Yours Alexander Büchler
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