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Adrian von Bidder made an interesting post in response to my post about Spanish wind power. He correctly points out that power sources that have seasonal variations and which may vary during the course of a day can not be used as the sole power source.
The ideal design would be to have wind power stations that are designed to have a peak power that is greater than the expected use for the country. Then when wind power is slightly below peak the entire use for the country could still be satisfied.
There are a number of power sources that can quickly ramp up, this includes hydro-electric and gas-fired power stations. Such forms of power generation could be used as backup for when wind and solar power are limited. Incidentally one thing to note about Solar power is that it is most effective during the day in summer – which is when there is the highest demand for electricity to run cooling systems. There is also an option for having the sun heat up rocks which can be used for generating electricity at night or at periods of peak demand. So eventually we could have all our energy needs supplied by solar and wind power.
If wind power was designed to exceed the demand at windy times there are a number of ways that it could be used. The first thing to do is to implement billing systems that vary the cost according to the supply. This information could be provided to customers via X10 (or a similar technology). Home appliances could take note of this information and perform power-hungry operations when it’s cheap. Your freezer could cool itself to -30C when electricity is cheap and allow the temperature to rise to -5C when it’s expensive. You could program your washing machine to start when electricity becomes cheap – usually a few hours delay before starting the washing is no inconvenience.
Ideally home power generation from solar and wind sources would be used. There is significant loss in the power lines that lead from power plants to the consumer, so there are efficiency benefits in generating power locally. A wind turbine for a home will give highly variable amounts of power, and the electricity use of a home also varies a lot. So batteries to store the power are required. When you have local battery storage you could use your batteries to power your home when electricity is expensive and use mains power when it’s cheap. Also if it was possible to feed power back to the main grid then home battery systems could be used to help power the main grid at expensive times (if the electricity company reimburses you for putting power back in the grid then you want such reimbursement to be done at the highest rate).
Adrian also mentioned turning devices off when leaving home. It is common practice in hotels that when entering your room you will insert your key in a holder by the door which acts as a master switch for all lights and some other electrical devices (such as the TV).
This same idea could be adopted for home use, not based on key storage (although this would be an option) but instead on a switch near the front door. Push a button and all lights turn off as do human-focussed appliances such as the TV and DVD player turn off (not the VCR), etc. There could also be a night option which would turn off the TV, DVD player, and most lights. Obviously at night you want bedroom and bathroom lights to still work but many things can be turned off.
This is all possible with today’s technology, small changes to usage patterns, and spending a little more money on technology. Currently you can get a basic solar power system for your house for about $10,000. That isn’t much when you spend $300,000 or more buying the house!
On Tuesday my Thinkpad was taken for service to fix the problem described in this post.
The problems I described were overheating, wear on the keyboard (from a minimum of 8 hours a day 7 days a week use) and a missing rubber foot on the base. The statement of work includes a replaced system-board, keyboard, CPU fan, and “cover(s)” (not that I can see any difference in that regard). No new rubber foot. Also they upgraded the BIOS.
It’s interesting to note that in the list of “diagnostics performed” they listed “HDD” – of course I removed the hard drive before giving it to them.
Anyway 2 days turn-around is pretty good service and I’ll ask them to post me a new rubber foot so I can stick it on myself.
Update:
The IBM support team were quite helpful about this and now have a set of misc small parts being couriered to me – it may arrive tomorrow or Monday.
It’s a minor annoyance that they didn’t fix everything when they had it, but shipping me a set of small parts is great service. With a bit of luck I’ll get some other parts that will be useful to me at some future time too. ;) My Thinkpad leaves warranty in a few months and I’ll be on my own for all future repairs.
For the first time I am actually considering paying for extra warranty support. I think that I’m one of the more expensive IBM customers in terms of warranty support. I typically go through one keyboard and one system-board per Thinkpad that I own. I guess that IBM make the most money from managers who have laptops always sitting on their desk. People like me who take their laptops everywhere, use them extensively, and wear things out (doing what laptops are designed to do) would be less profitable.
The latest news is that Spain has wind power as it’s main source of electricity. The second largest source is nuclear and the third is coal. This is due to some particularly windy weather recently, but Spain is also a world leader in both manufacture and installation of wind power systems.
Other countries should follow their lead. Wind power is very cheap once it’s installed, there are minimal ongoing costs and when things go wrong the scope of the problem is very small (unlike nuclear power plants which have the potential to contaminate large areas).
Sorry no link, this news is too new to be indexed by google.
Recently I bought a HP DL385 Opteron server at auction. It has an Opteron 265 1.8GHz dual-core CPU and is designed for SFF (Small Form Factor) SAS disks.
A friend told me that S-ATA disks would work in it and so would a faster Opteron CPU. I bought 3 S-ATA disks which work fine in a RAID-5 array. Unfortunately when I tried booting with the second CPU installed the BIOS said that it detected a CPU speed mismatch and would halt.
If anyone knows of a way of swapping Opteron 265 CPUs so that I can get a pair at the same speed then please let me know. I’d prefer to swap the 1.8GHz one for a 2.2 GHz one if possible, but the other way is also an option.
Debian is participating in the Google Summer Of Code (or Winter if you are in the southern hemisphere).
It would be good if we could get a SE Linux related project in. If you are interested in doing some SE Linux work (or other security related work) in this regard then please let me know. I’m interested in helping mentor for such projects.
This weekend I went to the Ballarat install-fest, mini-conf, and inaugural meeting of the Ballarat Linux Users’ Group (BLUG).
This was the second install-fest, the first one was quite successful so it was decided that there was demand for a second. I suggested that what we should do is get some of the more experience members of LUV to attend and give talks about their areas of expertise and make a mini-conference. I also suggested that we
hire a large vehicle to take a number of people to the meeting. Both my suggestions were accepted.
So on Friday evening I was in a Kia XXX with five other people from LUV on our way to Ballarat.
On Saturday we had the install-fest. We started at about 10AM, there were about a dozen people getting help installing Linux and many more attending the mini-conf and just hanging out. For lunch we had a BBQ. In the afternoon I gave a talk on SE Linux and then a brief impromptu talk on Poly-Instantiated Directories while the next speaker was setting up their laptop.
At the end there was the inaugural meeting of BLUG. The president was appointed, and there were some brief discussions about when to schedule meetings. I suggested that BLUG meetings should be either the day before or the day after LUV meetings to increase the incidence of speakers from other regions attending both meetings, my suggestion was being seriously considered at the time the meeting adjourned – LUV is a larger group and has better ability to get speakers from other regions. It was also agreed that a
weekend combined LUV and BLUG meeting would be arranged twice a year.
I traveled back to Melbourne by train which was cheap at $9 and comfortable. There was even a power point in the carriage (which I didn’t use as my laptop was charged and the location was not convenient). For the next such event I’ll try and arrange a group to travel on the train together.
The next thing to do is to find other regional centers in Victoria where we can do the same thing. Bendigo might be a possibility.
Also if you are a member of a LUG in a city please consider the possibilities for helping form a LUG in a regional center that’s nearby. I would be happy to provide whatever advice I can to help people replicate this success in areas surrounging other cities, so please email me if you have any questions.
A common criticism of fluorescent lights is the inability to use dimmers, as mentioned in Julien Goodwin’s blog.
However with some thought at the time the lights are installed this problem can be solved. The first thing to keep in mind is that an infinite number of levels of illumination (analogue scale) is not really required. In most cases two or three levels should do.
If you have two compact fluorescent lights that use 5W and 10W then you have the options of 5W, 10W, and 15W. If you have a large room to light (such as a lounge room) which needs 30W of fluorescent lighting for full illumination then you could have six 5W globes dispersed and have anything from one to six of them turned on to give different levels of illumination.
Of course if you don’t plan electrical work then it’s easiest to just use incandescent lights in those areas. As long as the areas that use the most light for the longest time have fluorescent lighting it shouldn’t make too much difference.
In response to a post on Planete Beranger, saving energy DOES matter. Sure you saving a few KWh isn’t going to make much difference on it’s own, but when a million other people do the same it all adds up.
The lack of public transport in the US causes more problems for the country than just environmental damage. It hurts the economy by making it more difficult for people to get to work. It will hurt the defence forces in the (unlikely) event of an invasion (trains are the best way of moving large numbers of troops, heavy weapons, and military supplies. It also hurts the national interest in decreasing the ability to react to civil emergencies. For example the entire population of New Orleans could have been evacuated in time using a single platform of a European station. If every city had multiple stations that had a reasonable number of platforms and multiple redundant train lines then evacuating civilians and bringing in emergency equipment and workers would be very easy. In the Netherlands train lines often run on top of dikes, this means that the dikes are very strong (if they can sustain the weight of a freight train then they aren’t going to be washed away by a wave) and that trains can still operate while flood waters are rising. If New Orleans is to be rebuilt to it’s former glory then the Americans should consider a similar design.
Large cars are a temporary issue. As fuel prices rise people will choose smaller cars. Also hopefully people will start to realise that 4WD and SUV vehicles are actually less safe than cars and stop buying them for perceived safety.
The Chinese government doesn’t worry about the same environmental issues, however they have more agressive targets for renewable energy use than most countries. It’s not a matter of being nice (they aren’t), but of looking out for their own self interest. It’s a pity that the governments of the US, Australia, and EU countries have not yet done the same – but it will happen eventually.
As for supermarkets using open fridges, if the vent the heat outside the building then it will be just part of the building air-conditioning system. Every adult dissipates about 100W of heat when at rest, when shopping it would be more than 100W. Get 100 people in a supermarket (not the peak business time) and 10KW would have to be removed by the A/C system without counting heat from lights (fluorescent lights dissipate about half their energy as heat, they are much more efficient than incandescent lights but much less than LEDs),
and heat from other machinery.
Finally, if you want to see changes in government policy then join your local Green party!
My Thinkpad has started to run hot recently. If I do anything CPU intensive then it will heat up to >80C and then turn itself off. When idling it seems to stay at about 60C when the ambient temperature is about 24C.
It used to not be like this, a couple of years ago I cracked a GPG pass-phrase by using my Thinkpad (as well as a few other machines) to run a brute-force attack lasting a few months. So a couple of years ago I could run at 100% CPU time for months on end and now I can only do that for a few minutes.
It seems that my Thinkpad may have accumulated dust in it’s fan from years of running 24*7. I run my Thinkpads 24*7 so that they can download email and large files while I’m asleep, because Linux suspend options have been lacking until recently, and because I use my laptop for a large portion of the day.
The problem I am having is similar to what I had with a previous Thinkpad. Are Thinkpads unable to handle 24*7 operation?
I just read an interesting blog post from December 2005 about the environmental impact of bio-fuels. It makes some really good points that should be studied by everyone who is interested in protecting the environment.
However this doesn’t mean that bio-fuels are inherently bad, just that some methods of production are bad.
The blog claims that reusing oil that had been used for frying would cover 1/380 of the fuel used for road transport in the UK. There are some technologies that have been recently invented to process farm and industrial waste into oil, some of which are already in production in the US. The volume of farm waste (and equivalent waste from restaurants) would significantly exceed the frying oil from restaurants and converting waste plastic into fuel would add even more. I’m sure that these sources of fuel from waste would add up to at least 1% of the current transport fuel use.
A better train system has the potential to halve the use of fuel for transport (or better), when living in Europe I never considered owning a car, the trains were so good and the car parking was so bad that it wasn’t worth doing. A combination of less cars and the cars being driven less would significantly reduce fuel use.
Hybrid vehicles and vehicles with smaller and more efficient engines could halve the use of fuel again (or better). Diesel hybrid cars that are currently being tested use as little as 1/4 the fuel of current petrol cars. Add further technological improvements such as the six-stroke engine and we could be looking at something better than four times the current fuel economy of cars.
I don’t think it’s unreasonable to assume that a combination of a good public transport infrastructure, fuel efficient vehicles, and government incentives for using both could reduce the transport use of fuel by a factor of 8. This would mean that fuel produced from restaurant, farm, and plastic waste (which I conservatively estimate at four times the volume of used frying oil) could account for more than 8% of the fuel supplies. The EU wants to have 5.75% of fuel oil to come from renewable sources, it seems to me that this is possible without importing any bio-Diesel from developing countries!
Electric cars could of course significantly decrease the use of fuel oil too. A Prius+ (Prius modified to take mains power) would be an ideal vehicle for me. I rarely make long journeys and rarely make multiple journeys in one day so I could use mains power most of the time. I estimate that with a Prius+ I would use no more than two tanks of petrol a year.
Then of course there’s the issue of market protection. It seems that every first-world country has a farming lobby that convinces the government to pay them to produce more crops than they can sell at market rate. Instead of subsidising food that is sold to other countries such government money could go towards subsidising development of bio-fuels. The US subsidy of corn production is a classic example of this, corn syrup can be easily fermented and distilled to make fuel – much better than eating the nasty stuff!
The book SE Linux by Example has been reviewed on Slashdot.
The issue of Perl scripts was raised for discussion. It is of course true that a domain which is permitted to run the Perl interpreter can perform arbitrary system calls – it can therefore do anything that SE Linux permits that domain to do. This is in fact a demonstration of how SE Linux does the right thing! If you want to restrict what can be done when executing the Perl interpreter then you can have a domain_auto_trans() rule to have Perl run in a different domain.
Restricting Perl (as used by one particular program) is actually easier than restricting a complex application run by users such as Firefox. Users want to use Firefox for web browsing, local HTML file browsing, saving files that are downloaded from the web, running plugins, and more. Granting Firefox access to perform all those tasks means that it is not restricted from doing anything that the user can do.
A claim was made that a novice users would not understand how to use SE Linux. The fact is that they don’t need to. I know many novice computer users who are running SE Linux systems, it just works! It’s more advanced users that have to learn about SE Linux because they configure their machines more heavily.
The essential difference between path-based access control and Inode based access control is that the standard Unix commands to control file access (chmod, chown, and chgrp) all operate on Inodes. If a file has 1000 hard links then I can restrict access to all of them via a single chmod or chcon (the SE Linux command that is comparable to chmod) command. AppArmor does things differently and implements an access control model that is vastly different to the Unix traditions. SE Linux extends the Unix traditions with Mandatory Access Control.
Granting different levels of access to a file based on the name of the link which is used is a horror not a feature.
I wrote this as a blog entry rather than a /. comment because my lack of Karma means that less people will read my /. comments than my blog.
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