That's the question I'm trying to solve right now. From wide range of cameras, I reduced to this choice, but the decision is now quite hard. Both have their advantages and disadvantages and there is not easy to choose as it was to cut down previous list. I used Google a lot in last weeks to find some experiences with both cameras, but none of them really helped me. Pentax pros:

• Shake reduction in body (saves money on lens).
• Dust removal from sensor.
• Modes like TAv.
• Manual tuning of white balance looks much easier to use and provides many options.
• Dust-proof weather resistant body (although I won't have matching lenses at beginning).
• Manual flash control - it won't pop up when I don't want.
• Dedicated RAW button (I probably will take most photos in JPEG, but I want to be able to switch without going deep into menu).
• In camera RAW development (I'm not sure I will use this).
• Won lot of awards this year, so it should not be a bad camera, right?

Pentax cons:

• Underexposure in some conditions (maybe I just set something wrong on camera in shop).
• Lower lenses availability in Czechia (but I'm in Japan for next few months, where it is not that big problem).
• No option in kit lenses.

Nikon pros:

• Faster AF.
• More lenses and accessories available (but I'm not sure if I really need them).
• Scene modes (but I might anyway stick with manual settings).
• A bit cheaper here.

Nikon cons:

• Feels slightly less comfortable in my hand.

From the list it is visible that I was able to find more pros and cons on Pentax. Nikon seems to do its job pretty well, but does not provide any extra gimmicks. This is also reason why Pentax is winner for now. I'll buy the camera sometimes during next week, so things can still change.

The short story: we lost the baby. "Cord accident". The long story: Sarah woke me up at about 2:30am on Tuesday morning in a panic because she'd woken up herself at about 2am, and realised that she hadn't felt the baby move since about 8am the previous day. I had a quick feel, but couldn't feel anything like his usual vigorous kicking, and eager to put her mind at rest, called Labor an Delivery at Lucile Packard Children's Hospital to see if we could come in. They said we could, so we jumped in the car and got there at about 3:25am. They hooked up Sarah to a fetal heart monitor, but after anxious minutes, they couldn't pick up anything, so they got out the ultrasound machine. It was pretty obvious from that that there was no movement. We'd lost him. So from about 4am onwards, we, well, tried to come to grips with the fact that we'd lost our baby. That we'd been robbed, 13 days from the finish line, and that we weren't going to be bringing a baby home to all the stuff we had ready for him there. The doctors briefly mulled over whether to have a C-section to deliver Joshua, as was the plan, or induce. Apparently it's psychologically better for the mother if she delivers naturally, since she doesn't have the constant reminder for 6+ weeks while she recovers from the C-section. However, the doctors decided that as nothing had really changed from a delivery point of view, and they wanted to do a C-section for reduced strain on Sarah's heart, they opted for a C-section. They managed to get a free operating room slot in the Stanford ORs, so they transferred Sarah over there, and they started performing the surgery at about 10am. Joshua was delivered sometime around 10:15am. I got to see him and hold him while we were still in the OR. He was perfect. 4 pounds 12 ounces. He didn't look that small. We were wondering if he was going to make 5 pounds or not. Maybe he would have by the 17th. I brought him around to show Sarah while she was still on the table, but it was hard to get him up to a good position that she could see him from, and she was a bit zonked out from all of the drugs. They finished up at about 10:45am, and took her to the recovery room, where they didn't really want me, so one of the nurses from Labor and Delivery took me back to Lucile Packard, to spend some time with Joshua. There she let me hold him for a while, and look at him, and take some photographs. Then she weighed him and measured him, and took some more photographs. The nurse was really compassionate about the whole thing, and it felt like we were there for a good couple of hours, which was good, because apparently Lucile Packard and Stanford don't really inter-operate very well, and whilst physically transferring a patient just involves wheeling them down a corridor, getting all the paperwork sorted out is a completely different story. So while Sarah was only supposed to spend an hour in recovery, she spent three hours there, because they were waiting on paperwork to release her, then waiting on a room to be available, then the right people weren't talking to each other, so they didn't know they didn't know that a room was available from midday. I forget what time we actually got out of recovery. The doctors, being the overcautious bunch of people that they are, wanted to keep Sarah in the Cardiac Surveillance Unit for 24-48 hours so they could check on her vitals post-delivery. They let us out of there late today. We're currently in a general ward. I thought they said it was for gynaecology patients (they didn't think it'd be terribly considerate to stick us in with all the other recovering mothers and their babies), but there's some male patients in here too, so I'm not sure what this ward is. In terms of coming to grips with things, they brought Joshua up to our room for pretty much as long as we wanted yesterday, and Sarah was more with it by then, so she could hold him, and we could take more photographs. It's been really hard. I was awake from when Sarah woke me up in the morning until about 10pm that night. Fortunately I was able to get a cot in the room with Sarah, so I could stay the night there. I'm staying here tonight as well. The obstetrician that delivered Joshua said that his umbilical cord was wrapped around his neck twice and once around his body, and was pretty tight around his neck. They can't say for sure that that's what happened, but it's a good enough explanation for us, and we're not going to have the little guy cut up for an autopsy, which may not tell us anything anyway. So we're taking some small comfort from the fact that we're able to make a healthy looking baby, and that Sarah's heart performed fine throughout the pregnancy and delivery, and that this was just one of those so very unlucky accidents. Apparently babies get their umbilical cords wrapped around their necks all the time, and most of the time it's not a problem. So we know that he didn't have any birth defects, and it wasn't because of something Sarah ate, or because Sarah got sick or anything. It's just plain bad, rotten luck. We'll most probably try again, but the next pregnancy is going to be hell. It'll be like walking on egg shells the entire time. Clearly, your baby isn't out of the water until he's screaming in the delivery room. There's a lot more I want to write, but I also want to get this finished and get some sleep, so here's a brain dump of what's been going through my head for the last 48 hours:

• Dammit!
• Dammit! Dammit! Dammit!
• We only had 13 days to go
• We just had the baby shower on Saturday!
• We just bought the last few things at Babies 'r' Us on Monday. He was probably dead by then.
• We were so ready. We'd gotten everything. We bought a cool jogging stroller! We bought a super-awesome safety table of a high chair.
• I never thought my Tuesday would end up like this when I went to bed on Monday night
• He looked so perfect. We've been robbed. He's been robbed.
• The little bugger was too active for his own good
• We were supposed to be having our Caesarian class the next day
• Should we try again? Can I handle seeing Sarah go through all the pain and suffering of another C-section?
• It's just not fair!
• I wouldn't wish this on anyone
• This sucks
• This just isn't fair
• We'll get through this

We've been very grateful for the near endless stream of visitors, phone calls and SMSes, and flowers. It's helped us not dwell on things, especially given all of our family is so far away. Sarah's Mum, who was going to arrive in 5 weeks, is now arriving on Friday, so that'll be good for Sarah. Sarah will hopefully be discharged on Friday or Saturday. We're planning on cremating Joshua, as it just doesn't seem right to bury him over here and then someday move back to Australia and leave him all alone. Current thinking is we won't have a funeral service. Here's what I emailed to the people we were going to send the birth announcement to:

Hi everyone, It is with heavy hearts, that we have to tell you that rather than announcing Joshua's birth on the 17th of September, we have to say that yesterday, we learned that we lost him, 13 days before he was to be delivered. Sarah woke me yesterday morning at about 2:30am, because she'd woken up at about 2am, and realised that she hadn't felt Joshua moving since about 8am the previous day. She tried a few things to get him moving, but they didn't work, so we hurried into Labor & Delivery at the Lucille Packard Children's hospital. There, they confirmed the worst, no heartbeat. Yesterday morning at about 10am, Sarah had a c-section so the doctors could deliver little Joshua. He was absolutely perfect, weighing in at 4 pounds 12 ounces (2.15 kilograms) and 26.7 centimetres (10.5 inches). Yesterday was a very long day. Sarah is currently recovering in the Cardiac Surveillance Unit (CSU) of Stanford Hospital (her aorta has been absolutely fine, the doctors are just being their usual cautious selves). It's a little bit up in the air as to whether she'll spend the entirety of her recovery in the CSU, or if she'll be transferred back to the Post-Partum area of Lucille Packard after 24 hours. (We hope that she does get transferred back, as the CSU isn't really used to dealing with post-c-section patients, particularly ones that have lost the baby). The obstetrician that delivered Joshua said that his umbilical cord was wrapped around his neck twice, fairly tightly, and once around his body. So whilst we'll never know for sure, it looks like it was a cord accident. That's a good enough explanation for us, so we're not going to have him autopsied. That's about all I can report at the moment. If you'd like to speak to Sarah, you can either call home and I'll try to keep Sarah's extension forwarding to her hospital room, or you can call my cell phone. I've got it on vibrate all of the time, and I'll answer if we're not in the middle of something. If you're calling from Australia, my extension at home will let you connect to my cell phone. If you're local, and would like to visit, we'd love to see you, just call ahead to check where we are. It's going to be hard, but we'll get through this.

Japanese professor and free software advocate Masayuki Ida is in The Netherlands, and yesterday gave a lecture about his activities in bringing free software to several Asian developing countries. It was interesting to learn what the state of technology is in a country as Vietnam, and why specifically free software is very welcome to change it. They are not interested in the pricing aspect, since a Windows CD is $1 there. Free software allows and stimulates its users to gain a much better technical understanding of a system, and there's a dire need for people with technical knowledge in the country. By using free software, they are making bigger leaps in their technological development. The professor wanted to do something typically Dutch afterwards, so a couple of us took him on a bicycle ride from Amsterdam to Ouderkerk aan de Amstel, along the Amstel river (known for naming both Amsterdam and a beer brand). He was friendly and very interested in how education works in The Netherlands. We once lost the professor - as it turned out we'd passed a windmill, which none of us locals even noticed, but the professor did and wanted to take some pictures of it. After a stop for a beer we returned to Amsterdam, delivering the professor at his next appointment (a bit late).

Earlier this year I blogged about using the twitter bot for Remember the Milk. I still use it fairly well, even though the SMS messages from the RTM come late a bit. It's working for me in order to get a good chain going for the thesis proposal. There are a couple other bots that I'm using which are on twitter as well.

The first bot that I use is the bot at timer. The timer bot will let you set a timer (surprisingly). You only need to send it a direct message with the amount of minutes as well as a reminder for you about what it was set for. For example, if you want to remember to plug the meter before it runs out in 40 minutes, just twitter 'd timer 38 plug the meter' to timer and in 38 minutes it will inform you that your timer is up. You can have multiple timers running at once, which is useful if you are perhaps having tea at a coffee shop while you are parked on the street.

Another bot I use is the gcal. Gcal is a connection to your google calendar through twitter. You can set up new appointments by messaging the gcal bot with something like 'd gcal Pick up joe at 7pm' or 'd gcal set up web application for judy tomorrow' and it will
add it to your calendar. I use it in the morning to track my weight. I just pull out my phone while I am at the scale and SMS 'd gcal my weight is XXX', and it adds the event as a day event on the day it was sent.

The last bot I will go over today is the mymm bot. It is slightly more complicated but still useful. When you're at the pump, you can direct message mymm a little info and get back the MPG that you have done since the last fillup. It helps me keep a tab on how good or bad I'm driving, which is a good thing. The car we drive usually gets about 24 MPG, but I learned through this that when I'm carrying a bunch of crap in the back, the MPG drops 3-4, so it's better for me to have an empty trunk.

I'm sure there are a bunch of other useful bots out there (ququoo is one, which I may cover in another post), but these are the most useful that I've found so far. Twitter is turning out to be much more useful than just random status updates.

Anyone who has done an operating systems 101 course is familiar with the standard hierarchical page-table structure. This is essentially a radix-tree where bits of the virtual address are taken as indexes into an array of pointers, each pointing to the next level down or, at the leaves, to a physical entry. One potential issue with this style of page-table is with a very large, very sparse address space (such as in a single address-space operating system) there will be many intermediate steps with possibly only a single translation at the end (i.e. lots of single pages scattered all around your address-space). Thus we can add a bit-field guard to each of the entries in the page table (Liedtke, 1994) to help indicate only those paths through the tree which are valid (similar to a Patricia tree). Translation first proceeds as usual; the top bits are used as an index into the top level table. However, each entry now contains extra information about further valid addresses. The guard is masked against the next bits in the virtual address; if it matches (e.g. in our example is 0x2) the next step can proceed directly to the leaf node, bypassing the middle look-up. The entry can be marked as either final (i.e. pointing to a leaf node) or intermediate, in which case the process continues with the next level (which also has its own guard, and so forth). Any entry that does not match the guard is known to be false, and therefore a fault can be raised. To examine this further, consider that we know that each page in our 24-bit address space above is 4KiB, thanks to the 2¹² = 4KiB offset. Therefore each of the 16 possible values of the top four bits selects 1MiB of the 2²⁴ = 16MiB address space; e.g. 0x0 selects the first megabyte, 0x1 the second and so forth. The second 4 bits selects a 64KiB region of this 1MiB, and the last 4 bits selects a 4KiB region of this 64KiB region. This scheme could work quite well if we were using only 16 pages each separated by 1MiB. Each of these pages would only require an entry in the top level with an appropriate guard which could then be marked as final and point directly to a physical frame. Once things become less sparse however, we need to start filling in middle levels. If you have 2 pages within a 16MiB region, you need at least one extra bit of address to tell them apart. If you have 3 or 4 pages, you need at least 2 bits to tell them apart, and so forth. It would therefore be beneficial to have variable level sizes to dynamically adapt and create the most efficient lookup possible given the address space layout of a process. For example, if you knew your process was only going map pages 0x123 (100100011) and 0x124 (100100100) a good option would be to make your top-level only two entries (i.e. check the top bit) with a guard on the entry at index 0x1 of 00100. You then need a second level with 8 pointers to differentiate the remaining 3 bits (each of these would be final and hence point directly to a physical page). The more pages you start mapping, the less bits you can discard with the guard. If you follow this through to a guard of 0 bits you end up with a linear page-table. It has been shown (Elphinstone, 1999) that fixed level sizes with 16 entries tends to work well. For a 32-bit address-space with 4KiB pages (e.g. 12 bits offset) this leaves 20 bits to be mapped by the page-tables; with each level mapping 2⁴ bits this means a 5 level tree. The guard values provide enough path-compression that the table is not constantly walked. The disadvantage is that it may "over-allocate" meaning more space is dedicated to page-tables than strictly required. Deciding where and when to split levels, what size indexes to put at each level and updating all the guard values dynamically to make the smallest, most efficient page-table would create a variable-radix page-table (Szmajda and Heiser, 2003). In summary, a guarded page-table is more useful the more sparse your address space is. A variable-radix guarded page-table is complex, but could offer advantages for implementing variable page-size support and thus having positive effects on TLB coverage.

I've found some time for quicklist, finally, to move the port on to a second pre-release. New additions include a Recent Files submenu and GtkHTML report engine but the Sort and Filter options are not complete and adding a new report is problematic.
quicklist is now ready for some translations (the first one identified a problem in pre1 that prevented certain strings from showing up as translated). Also added a prototype manual using docbook that I've made available as HTML for dwww and making the docbook file itself available to yelp.
Currently, I'm undecided just where QuickList will fit between pure-Gtk2 and pure-Gnome2. pre2 uses libgnomeprint and libgnomevfs but yelp would bring in the main gnome libraries so yelp is just a Recommends and only as an alternative to dwww:

Recommends: www-browser, dwww yelp

I hope to find some time to fix the remaining bugs but if anyone fancies helping out, see http://quicklist.sourceforge.net/ and take a look at the current CVS prior to the pre2 upload. CVS provides a method to build the updated code docs for developers (rather than the Manual which is aimed at users) using doxygen - the version on the website is out of date. This includes a list of bugs and ToDo items - most of which are centred on removing the last vestiges of the original QuickList code and refactoring to make full use of libglib2.0-0 functions like GList and GHashTable instead of fixed length multi-dimensional arrays.

Time to revisit this topic. I asked debian perl for advice on packaging a CGI with modules and my current solution is to use ExtUtils::MakeMaker - I'm just writing the PL files which will generate the configuration files. I also took a look at Module::Build and PAR::Tutorial but I'm not convinced that they're both as portable and as smooth as if I can do it all from MakeMaker. There are occasional posts about Module::Build problems on lists like this one on ledgersmb-users which worry me. After koha-1.2's bespoke installer, I really want to make it as easy and simple as possible, for both development and use. There are also periodic debates about M::B at perlmonks too. Maybe we can use PAR later, like this perlmonks post suggests and apparently KrangCMS does. Now, what have I missed? (2007-09-07: 3 comments)

Being impressed by prices of these toys here in Japan, I decided to finally buy one. This decision was quite easy, but it implies much harder one - which one to choose. Looking at my money availability and what do shops here offer, I have five possibilities: Canon EOS Kiss Digital X (EOS 400D in Europe), Nikon D40x, Nikon D80, Pentax K10D or Sony 100. Well it's hard choice. However for now I prefer something with shake reduction, what limits selection to either Pentax or Sony (or some of the others with lenses which do the same). And from these two, Pentax looks like much better choice. As this will be my first SLR, I don't have to stick with same vendor to be able use my equipment, but I'm much more interested in availability of add-on lenses and other stuff. And in this are seem to win Nikon and Canon. So that are points for the other side of the match. I played with all these cameras in shop, but I really didn't find any of them much better than others. I just take few shots and nothing surprised me there. And I was able to switch them all from Japanese to English quite quickly ;-). So this step did not decide anything. Reading various reviews also didn't help much, as each camera has advantages and disadvantages... For now my temporarily winner is Pentax, but I think I should find some more convincing arguments before buying it :-). PS: I know there exists a bit cheaper variant of Pentax branded as Samsung GX-10, but I haven't seen it anywhere here in shops.

Well, checking ISO-3166-2 data for my country, I found out that France officially listed the following subdivisions in ISO-3166-2:

• 22 metropolitan regions
• 4 overseas regions/departments
• 96 metropolitan departments
• 2 territorial collectivities
• 4 overseas territories

Thankfully, they didn't list the hundreds of "cantons" and "arrondissements", nor the 36,000 municipalities. Ah, and France is also one of the very few countries that have *more than one* ISO-3166 code as, besides the logical FR, we have GP for Guadeloupe, GF for Guyane, MQ for Martinique, RE for R union, YT for Mayotte, PM for Saint-Pierre-et-Miquelon, NC for New Caledonia, PF for French Polynesia, TF for the Southern French Territories and WF for Wallis et Futuna. Dammit..:-) Even our British friends didn't steal codes for Scotland or Wales...

Finally we (Frank Lichtenheld, myself) took the time and upgraded the host for packages.d.o to etch. This was absolutely needed, as pdo was always running with a very high load for the machine, and the new code needed some etch-specific packages/package versions. So, today we went, turned off old pdo and upgraded it. It got a new kernel and lots of new package (versions) from etch, including apache2-mpm-worker. It is now accessible for everyone again, and its running the new code. Which does look nice, is way better and also much faster. Uses libapache2-mod-perl2, database files (instead of textfiles and grep) and a nice new layout. And possibly much more changes, but Frank will send a mail about it later. (At the time of writing this blog pdo is still generating its initial database files, so not everything working atm, but when that first run is done it will be MUCH faster in the future…) Say thanks to Frank for his work on pdo! Update: Thanks to the new and fast code (a full update now only takes real 40m26.415s, user 16m36.538s and sys 0m50.055s instead of hours), packages.d.o will now update twice a day, with a push directly after the mirror update has happened. Which should greatly help to reduce the “packages.d.o is out of date” symptom…

Just a couple of days ago we finally opensourced Ganeti, a cluster virtualization platform based on Xen. In the last few months I joined the Ganeti team, which is based in Zurich, and worked with them on the development of this software! I’m really happy now to be able to share the result of what we’ve been doing with the rest of the world! For more information you can have a look at the project page! Of course an ITP has been filled! (ok, actually two because I didn’t notice someone in my team had already done one!) PS I’m away for the weekend, forgot my charger and am running out of battery! I’ll be back online on monday, I guess! :)

Here is a transcript of a lecture by George Monbiot about climate change and what we need to do. The latest scientific evidence suggests that we need to cut emissions to zero by 2030 to avoid significant increases in the sea level over the next century, George describes some options that will form part of a solution to this problem. Below are my comments on what I consider the most interesting (the ideas that I hadn’t heard of before), I recommend reading the full article for the rest.

1. Have a carbon ration for each citizen. Wealthy people who want to use more resources could buy carbon rations from poorer people on an open market. That way people who use less than their ration still have an incentive to save more because the extra savings are worth money! As everyone would then have a financial incentive to reduce emissions there would be a lot of new development of methods and technologies for eliminating or compensating for carbon emissions, capitalism works!


2. Build battery powered cars with interchangeable batteries. The idea is that you rent a battery from a fuel company, and whenever it runs low you go to a service station and swap it for a fully charged battery (for a small fee). If doing this the service station could use cheap night-time electricity to charge the batteries, and the batteries that are charged could be used to put electricity back into the grid at times of peak demand. A common idea is to have Prius+ type vehicles charge from the grid when not being used and then sell electricity back to the grid at peak times. Implementing such a system for millions of homes is technically challenging and expensive. But having a much smaller number of service stations sell larger quantities of electricity back to the grid is easier to manage.


3. Reduce air travel by 90%. I wonder how much of this can be achieved by using high-speed trains for all national travel systems and for most travel within the EU. I have often travelled between Amsterdam and London by train, it’s much more civilised than flying.


4. Classic quote from George on John Howard: “if Howard believes a slight reduction in consumption is a recessionary measure he ought to see what a total reduction of land area would be as a result of the melting of the west Antarctic ice sheet. The two things are just completely out of proportion..”

George Monbiot also has recently released a new book Heat: How to Stop the Planet from Burning.

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The 4th and hopefully last alpha version (I expect the next one to be a beta) of Gnash, the GNU’s free Flash player has been released yesterday. There are many important changes, but the most relevant thing you’ll notice is that it’s by far more stable than the previous one. Gnash supports right now the majority of Flash opcodes up to SWF version 7, and a wide sampling of ActionScript 2 classes for SWF version 8.5. The program is still under heavy development and Flash version 9 and ActionScript 3 support are also being worked on. Debian SID has right now one of the latest release candidates for this version, and 0.8.1 will probably be in the repositories soon. As it is expected that in one or two versions it will be able to select between the different possible backends, we’ve decided to have just one package with pre-selected options in the repositories. AGG is probably the most conservative version that will work for everyone, and even though OpenGL might be better for certain graphic cards, we’ve decided to play safe. In any case, I’ve also made some unofficial packages for those who want to try different configurations of Gnash, like, as I said, using an OpenGL backend.

I just needed to test something so I mounted the filesystem of one of my Xen domains in the Dom0 and chroot’d into it (I didn’t need the overhead of running a DomU for a quick test). Then strangely I found that my chroot environment had no apt-get and no dpkg installed. After a small amount of thought I realised that I had accidentally mounted the filesystem for a Fedora image instead of a Debian image. It seems to me that it might be a good idea for distributions to have shell scripts replacing the package tools for other distributions. For example dpkg on a Fedora box could be a shell script that runs echo “This system is running Fedora, you want to use rpm instead of dpkg”. Such a command would have saved me a couple of minutes of thinking. This may sound trivial, but if you consider the number of people who make such mistakes (and the even larger number of people who don’t realise that there is even more than one package tool in existence) then wasting a few K of disk space on every system to help them seems like a good idea. The minimum size of new hard drives that you can purchase seems to be 36G nowadays. So it’s not as if this would really cost anything. Please leave comments to tell me if I’m being sensible or silly. If the idea is regarded as good I’ll start filing bug reports.

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GPL and Business FAQ I sometimes happen to be in a dialogue like this:

X: According to GPL, you can sell copies of your software at any price you want, right? Me: Right. X: But your customers can in turn sell copies of your software at any price they want, right? Me: Right. X: So, the only way a GPL developer can make money is by charge for development of their software? Me: Not only for development: also for maintenance, improvements, customisation, installation, training, gadgets, support...

The market is quite big, actually. In fact, one can even make business by selling the software in a box, if one makes a box that people would like to have (for example, including things like useful documentation, a few gadgets, a support contract and a pony). The idea is that the business of selling software alone is a useless extortion that provides no particular benefit to the user (and in many cases, no particular benefits to the developer either). If you put that aside, there is a plethora of ways to charge the customers more, and for things and services that are useful to them and make them happy. Actually, if you develop a GPL software for someone who is then happy about it, they may then pass it on to other people in the same sector. Who then maybe need help with installation, support, maintenance, custom features, training, gadgets and ponies. If your software hits the spot, a niche market can end up growing by itself. The last discussion on this topic then ended up with another question:

X: Ok. But to do a good job you have to be many people at once: for example you sometimes need to be a sysadmin as well as a developer. Me: Yes. Being many people at once is what starting a company is all about.

He complained that answers like these could not be found in the Selling Free Software article of FSF: in the meantime I'll publish them here. The license of this post is GPL. The FSF and any of their regional chapters are welcome to use all or part of this text, with or without modification as they see fit, alone or included in documents that use any license they see fit, even some of the not really free ones they use sometimes, such as the one used by Selling Free Software itself :-P

BMW has released a new prototype hydrogen powered car. The bmwworld.com web page about it claims the cruising range is 190 miles. Added to the 400-mile range of the normal fuel tank, the 745h can go 600 miles between fill-ups. The first issue is that 10 miles are not accounted for (maybe it finishes the 190 miles of hydrogen power at the top of a hill). But more seriously the hydrogen needed to drive for 190 miles would take as much space as petrol needed to drive for 646 miles (hydrogen needs 3.4* the volume to store an equivalent amount of energy). I wonder if that BMW has any space left in the boot/trunk? Now we have some green bloggers praising BMW. An internal combustion engine that burns hydrogen will not give no emissions other than water vapour, it will produce some nitrogen oxides. The processes to produce hydrogen for fuel all consume unreasonable amounts of energy (more than is required to charge a plug-in hybrid). BMW demonstrates their level of interest by giving the cars to some celebrities. This gets some PR but no analysis of the performance. They also introduce the prototype based on one of the most expensive models (the 745) which you almost never see on the roads. If they produced a 318 or 520 that ran on hydrogen it would demonstrate some level of interest in getting this working for the mass market. If BMW wanted to make their cars more environmentally friendly they would start by adopting some of the technology from the Prius. Rumour has it that part of Toyota’s plan to make money from Prius development is in licensing the technology that they patent. A couple of years ago I test drove a BMW 316 and a Prius. The Prius was very quiet and gave a smooth ride (you might call these luxury features), and also gave decent performance (it’s widely regarded that luxury cars should perform well - pity the BMW 316 is a slug). In Australia the concept of “badge engineering” of cars is well established. When government subsidies favoured large manufacturing runs the Ford Laser and Mazda 323 were essentially the same car. Maybe BMW could adopt this concept and sell a re-badged Prius i-tech with a few extra luxury features as a BMW 4 series (it’s a much better car than the 3 series BMW). Finally bmwworld.com has an amusing FAQ about hydrogen power, here are some of the mistakes that they make:

1. They say “About 45 billion kilograms (50 million tons) [of hydrogen] is produced every year enough hydrogen to fuel 250 million fuel cell cars“, but only if the average fuel-cell car uses 180Kg of fuel per year. According to Wikipedia hydrogen has slightly more than 3* the energy density per mass than petrol, so 180Kg of fuel would be equivalent to 540L of petrol per year. The Australian Bureau of Statistics states that in 1996 the average annual distance travelled by car (it’s not clear whether this is per car or per person) was 14,600Km while among the countries listed the lowest was Japan with 10,130. When efficiently using hydrogen in a Prius (that is quoted as using 5.4L of petrol per 100Km) you might expect that 540/5.4*100=10,000Km could be travelled on the 180Kg of hydrogen. So the FAQ claim that 250M cars could be powered by the current hydrogen production would only apply if the cars are of Prius efficiency and driven the typical distances of Japanese drivers, or the cars were 46% more efficient than the Prius and driven in the Australian manner. Of course in the US things are even worse with 17,862Km being the average distance driven which means that their hypothetical fuel-cell car would need to be 78% more efficient than a Prius.


2. They state that “the majority of merchant hydrogen is produced by a process called steam methane reforming“. Why not just run cars on methane then? Anything that burns can be used to fuel cars, and methane has a much higher boiling point than hydrogen so it would be easier to store and transport (see the Wikipedia page on methane).


3. In regard to hydrogen production they say “about 95% of the total global hydrogen production is captive meaning it is used at the site where it is produced“, that is of course because it’s difficult and expensive to transport hydrogen.


4. The final amusing fact is that it is noted that most hydrogen comes from fossil-fuels. What problem are they trying to solve here? Hydrogen isn’t going to help the environment if it comes from fossil fuels, it will be more expensive than other fuels. Apart from getting government grant money for BMW it doesn’t seem to do any good.

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"BOWN. Walter Sydney (Wally). Passed away on Monday, August 20th, 2007, aged 74 years. He will be greatly missed by all of his family and friends. The funeral service will be held on Thursday, August 30th, 12.30pm, Weston-super-Mare Crematorium. Family flowers only, donations if desired for Weston Hospicecare, c/o The Elms Funeral Directors, 50 Baker Street, Weston-super-Mare. Telephone 01934 616006."

(From the Weston & Somerset Mercury, 23rd August 2007 issue) So I'm not blogging much just now. I think usual service should resume Friday 31 August.

BMW has released a new prototype hydrogen powered car. The bmwworld.com web page about it claims the cruising range is 190 miles. Added to the 400-mile range of the normal fuel tank, the 745h can go 600 miles between fill-ups. The first issue is that 10 miles are not accounted for (maybe it finishes the 190 miles of hydrogen power at the top of a hill). But more seriously the hydrogen needed to drive for 190 miles would take as much space as petrol needed to drive for 646 miles (hydrogen needs 3.4* the volume to store an equivalent amount of energy). I wonder if that BMW has any space left in the boot/trunk? Now we have some green bloggers praising BMW. An internal combustion engine that burns hydrogen will not give no emissions other than water vapour, it will produce some nitrogen oxides. The processes to produce hydrogen for fuel all consume unreasonable amounts of energy (more than is required to charge a plug-in hybrid). BMW demonstrates their level of interest by giving the cars to some celebrities. This gets some PR but no analysis of the performance. They also introduce the prototype based on one of the most expensive models (the 745) which you almost never see on the roads. If they produced a 318 or 520 that ran on hydrogen it would demonstrate some level of interest in getting this working for the mass market. If BMW wanted to make their cars more environmentally friendly they would start by adopting some of the technology from the Prius. Rumour has it that part of Toyota’s plan to make money from Prius development is in licensing the technology that they patent. A couple of years ago I test drove a BMW 316 and a Prius. The Prius was very quiet and gave a smooth ride (you might call these luxury features), and also gave decent performance (it’s widely regarded that luxury cars should perform well - pity the BMW 316 is a slug). In Australia the concept of “badge engineering” of cars is well established. When government subsidies favoured large manufacturing runs the Ford Laser and Mazda 323 were essentially the same car. Maybe BMW could adopt this concept and sell a re-badged Prius i-tech with a few extra luxury features as a BMW 4 series (it’s a much better car than the 3 series BMW).

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