Hi David
At the present time I'm just looking for something to do that may be useful to someone. So I haven't looked at the cost of any of this, but my simple system is something that works and doesn't cost much. Passive radiative cooling is a subject that interests me and thanks for your info. I'm not so sure about cooling water to condensate it. The problem as I see it is to maintain a cool surface while the air with the water flowing past it is warm. My idea was to cool buildings or food or whatever with it and it is worth a look. As I recall there is a bandwidth between about 8 micrometers and 11 micrometers that is open to the universe and you just have to keep the transmitter open to the sky away from any foliage or whatever. It is an interesting topic and I will study it. Ken Gotberg --- On Sun, 8/1/10, David L. Hagen <[email protected]> wrote: From: David L. Hagen <[email protected]> Subject: [Gasification] Water purification costs, radiative condensation To: [email protected] Date: Sunday, August 1, 2010, 7:48 PM Ken Gotberg Complements on exploring options. One review of water purification costs is: Evaluating the costs of desalination and water transport Yuan Zhoua, Richard S.J. Tol December 9, 2004 https://www.fnu.zmaw.de/fileadmin/fnu-files/publication/working-papers/DesalinationFNU41_revised.pdf Encourage you to compare radiative cooling and water condensation vs deliquescent absorption, condensation & regeneration. See thesis by Torbjorn M.J. Nilsson Optical Scattering Properties of Pigmented Foils for Radiative Cooling and Water Condensation: Theory and Experiment Chalmers Tekniska Hogskola, Dept. Physics, Goteborg Sweden 1994 ISBN 91-7032-941-9 Bibliotekets Reproservice Goteborg 1994 "A 390 um thick foil with TiO2 and BaSO4 pigments was produced and was found to have a fairly high emittance in the thermal infrared; it was therefore used in outdoor experiments. During drought months in Tanzania, the foil condensed 1.19 litre/m2 in a semi-desert." See also: Radiative cooling during the day: simulations and experiments on pigmented polyethylene cover foils NILSSON T. M. J. <http://www.refdoc.fr/?traduire=en&FormRechercher=submit&FormRechercher_Txt_Recherche_name_attr=auteursNom:%20%28NILSSON%29> ; NIKLASSON G. A. <http://www.refdoc.fr/?traduire=en&FormRechercher=submit&FormRechercher_Txt_Recherche_name_attr=auteursNom:%20%28NIKLASSON%29> ; Solar energy materials and solar cells <http://www.refdoc.fr/?traduire=en&FormRechercher=submit&FormRechercher_Txt_Recherche_name_attr=listeTitreSerie:%20%28Solar%20energy%20materials%20and%20solar%20cells%29> *ISSN* 0927-0248 <http://www.refdoc.fr/?traduire=en&FormRechercher=submit&FormRechercher_Txt_Recherche_name_attr=identifiantsDoc:%20%280927-0248%29> 1995, vol. 37, n^o 1, pp. 93-118 (68 ref.) (Caution: In tropical areas, cloud cover would reduce the radiative cooling.) Regards David L. Hagen HagenDL {at} ASME.org _______________________________________________ Gasification mailing list [email protected] http://listserv.repp.org/mailman/listinfo/gasification_listserv.repp.org http://gasifiers.bioenergylists.org http://info.bioenergylists.org
