Archive for December, 2008

David MacKay: Sustainable Energy – without the hot air

December 24, 2008

Cambridge physics professor D. MacKay has written a highly unusual book on “alternative energies” and our energy use. I just started reading, and it is probably the best I ever read on this subject. Numbers and not adjectives, precise and crystal-clear writing style… Even if you do not agree with his climate discussions, the book is a gem and should be your next reading. It is available in print and also (quite extraordinary!) as a free download (PDF file is 50 MB, 368 pages) on the web at http://www.withouthotair.com/Wiki.html.

Le fardeau de l’effort (Robert Goebbels)

December 23, 2008

Former Minister of Commerce Robert Goebbels wrote in Sep. 2008  a very good article in the weekly journal “Letzebuerger Land”. You may find the pdf version here (in French).

Minister Goebbels is the only active Luxembourg politician I know of (he is now a member of the European parliament) who has not joined the hysterical AGW chorus. He is an absolute exception amidst his parroting colleagues, and has to be complimented for his courage and his rigorous analysis of the political “climate change” mantra. His writing is extremely lucid and clear, and always a pleasure to read.

Hat tip to L.M.

Poll added to home page

December 23, 2008

I added a small polling screen to the home page (using PollDaddy, which is really easy to insert into a html page).

poll_dec08

If you want to vote, please feel free to do… it’s absolutely anonymous. We will conclude in a couple of weeks.

NOx sensor repaired

December 23, 2008

I finally managed to “repair” the NOx sensor. Actually, nothing was broken; probably a charcoal particle used in the main scrubber partially blocked the air flow, leading to a cascade of shutdowns (heater, ozone generator etc…) The air to be sampled is sucked by a pump through the sensor chamber; there it reacts with an extremely high ozone enriched air, and the chemiluscence of the reaction O3 + NO (detected by a photomultiplier) is the signal that is proportional to the NO concentration. The high O3 content of the air leaving the sensor and entering the pump has to be neutralized, as the aggressive O3 would rapidly eat away the membranes of the pump. This ozone destruction is done in the  large charcoal filled scrubber, which caused the malfunction. Usually a blocking of the air flow is readily detectable, because the flow is constantly monitored. Here flow seemed normal, but pressure was a bit too high.  Whatever the real cause, removing all charcoal, cleaning everything up and refilling carefully solved the problem!

Equipment problems

December 13, 2008

Running the meteoLCD station is never painless. Even if most of the equipment works reliably, from time to time problems are rising fast, and usely in a bundle. The main computer reading the radioactivity sensor broke down without any hope of repair. An identical spare that could have been used was dead on startup (no graphics). The image of the original computer saved for cloning was corrupt. The software written by Claude Baumann to drive his amazing serial to voltage converter (*)  was missing…. After a lot of pain, and with the help of Claude, I put up a “new” computer, which is running fine (“new” means 7 years old!. Machine runs Win2k and has a PIII processor).

A second problem: the NOx sensor shows a fatal “ozone generator” fault after I changed the charcoal in the main pump.  NOx is measured by a chemiluscent reaction with strong O3 gas, and this O3 has to be destroyed before eating away all plastic membranes of the pumps.  So there is quite a lot of charcoal in use; a problem is that a grain gets stucked somewhere in the tubing and lowers the air flow below the acceptable minimum. For the moment the air flow is normal, so the problem seems to hide deeper in the inner parts of the sensor. I am not sure if I will be able to do this repair. In that case, the sensor will remain down up to the next visit of the Envitec technician.

(*) Claude built a device which is inserted into the serial RS232 line between the computer and the Bittsens gamma counter. This device uses a PIC and ancillary electronics to fetch the data out of the serial stream and convert it to a voltage readable by the main data logger. Works like a charm!

Lasst uns Kioto endlich begraben!

December 13, 2008

I wrote a comment that was published in the Luxemburger Wort (Luxembourg’s largest daily paper) in the “Analyse und Meinung” section on the 9th Dec. 08.  Here the link to the page (text is in German, pdf).