Geek stuff – Page 91 – a sibilant intake of breath

Pumped hydroelectric storage in Wales

Snowdonia contains more than just some of the United Kingdom’s finest mountains. From a climate and energy perspective, the Dinorwig Power Station is rather interesting. It has a maximum output of about 1800 megawatts (MW) and was intended to store excess power from nuclear stations, during periods when their output exceeded demand.

The system takes only 16 seconds to ramp up to full output, and can maintain it for six hours. Because of backup batteries and diesel generators, Dinorwig is also able to restart itself even if the rest of the national grid has failed. The facilities two reservoirs are separated by 500m of vertical distance, and it stores about nine gigawatt-hours (GWh) of total energy. It is 75% efficient at turning surplus electrical energy into gravitational potential energy in raised water, and then back into electricity again at times of peak demand. Since it can buy electricity at times when demand is minimal (thus making the power cheap) and sell it when power was expensive, it was able to pay itself off in ten years. Along with three other British facilities, there is a total pumped storage capacity of 2.8GW.

This is a technology that could make a lot of sense for Canada. As we build more renewables – such as wind farms – there will be periods of excess energy production. By building new pumped hydroelectric facilities, or adding the capacity to existing dams, we will have a way to store some of that for when it is needed.

Contributing to Project Honeypot

Spammers are one of the most annoying natural enemies of the blogging community. They waste the time of site administrators who must install anti-spam systems and dig through suspicious comments to pick out real ones. They waste the time of users who are forced to jump through hoops like site registration and CAPCHAs.

One way to help fight spam is to participate in Project Honeypot. If you run a website, they will give you a script to add somewhere. Then, you add links to the script that robots will follow, but not people. This allows the project to catalogue the IP addresses of robots, as well as track the general spam problem globally. People who run websites but don’t control the hosting (for instance, people with blogs on Blogger.com or WordPress.com) can add ‘QuickLinks’ which serve a similar function.

People running WordPress blogs can also use the http:BL WordPress Plugin to take advantage of Project Honeypot’s data and block spammers and harvesters of email addresses.

Setting up a honeypot only takes a couple of minutes, and gives the satisfaction of knowing you are helping to make the internet a slightly more civil place. In addition to running a honeypot and using the http:BL plugin, this site has a wiki protected with Bad Behaviour, a blog protected with Akismet, and spam defences built into .htaccess.

Scrolling in XP and Mac OS X

For those with a scroll wheel on their mouse, Mac OS has one nice feature that is annoyingly absent in Windows XP. In Mac OS, if you put your mouse cursor over a window and scroll, it scrolls the contents of that window – a document, a webpage, whatever. In Windows XP, it will only scroll if it is the ‘active’ application, and will ignore scrolling when the cursor is pointed elsewhere.

The difference may have to do with some deep mechanism by which Mac and Windows applications interact with the operating system, or it could be a minor configuration choice. Either way, the Windows approach is annoying.

Of course, Apple doesn’t do everything right. My fancy wireless Mighty Mouse is over in a dresser drawer somewhere, too annoying to use. Instead, I am using an old $20 Microsoft optical wheel mouse.

The Aero Ace – a neat RC toy

The other day, I bought an Air Hogs Aero Ace radio-controlled aircraft, and I have been having a lot of fun with it since. The design is very simple, with two pager motors driving propellers and no control surfaces. Altitude is therefore controlled entirely through thrust, with turns accomplished by changing the relative power of the two motors. The biplane design is very stable, and capable of making fairly soft landings even without any power or control.

Flying it well requires about a parking lot of space, and it is easy to get it up to fifty feet of altitude or so. Given the very low weight, it only works well indoors or in very still weather. The foam body is very crash resistant. I have crashed mine literally hundreds of times into walls and concrete lots, with no structural damage.

The planes are fairly inexpensive (about $40) and can be ordered online. They run on 6 AA batteries, kept in the transmitter. The plane itself contains a lithium polymer battery which charges using a wire from the controller. Charging takes about 30 minutes, and gives 10-15 minutes of flight time. They are available in three frequencies, so that more than one can be flown in the same area at once (mine is frequency A). It would definitely be fun to play around with a couple of them in the same space.

The Dunning-Kruger effect

The idea of the Dunning-Kruger effect is that people who are incompetent at something often lack the skills necessary to appreciate their own incompetence, largely because the skills required for self-examination are similar to those required for competence in the task being evaluated. As discussed in this video, this effect seems to hold in areas as diverse as appreciating what people in general will find funny, grammar, and logical reasoning. A similar phenomenon shows up in surveys where the great majority of drivers claim that they are in the top 50% of drivers, ranked by skill. Obviously, many of them are overestimating their abilities, or underestimating those of their peers.

It would be interesting to see if it holds in relation to climatic science. As an experiment, people could be given a test that evaluates whether they can respond intelligently to scientific information about climate change. This could include things like whether they understand the difference between the stock of greenhouse gasses in the atmosphere and the flow of those gasses into it. If the pattern that emerged from scoring those tests and having people self-assess their competence held to the Dunning-Kruger pattern, that might help explain just how challenging it has been for the general public to acquire a working knowledge of climatic science, and ability to identify and reject bogus arguments about it.

An elaboration of the Dunning-Kruger experiments provides interesting additional insight. Highly competent and highly incompetent people are brought back, after having taken a test and rated their performance relative to others. They are then given a sample of other people’s responses to grade. Apparently, competent people realize that they previously overestimated the competence of their peers, and adjust their self-assessment to better match their position in the real distribution. This effect is apparently not seen in highly incompetent people, who fail to recognize their own mediocrity, even when confronted with evidence of it.

Patent reform idea

The trouble with patents is that they block people out of using the latest technologies and techniques. Sometimes, that means one manufacturer can offer things their competitors cannot. Sometimes, it means that firms can effectively block technologies that would otherwise compete with them. The question, then, is how to encourage innovation without permitting such barriers.

One idea that comes to mind is state support for innovators: invent something useful, and the state gives you a lifelong pension with a value proportionate to the value of the invention. They then distribute it for everyone to use for free. The size of the pension could be based on the number of dollars that get spent implementing your idea, with larger amounts for innovations that people really pour money into using. The state could fund the system with higher taxes on businesses and consumers. Consumers benefit because best practices spread more rapidly, and the market overall benefits because firms are less able to undertake anti-competitive behaviours.

There is, of course, the issue of pre-existing patents. One way to deal with that would be to take the age of the youngest patent holder, calculate a maximum plausible remaining lifespan, and decree that all existing patents will expire at that point, including those held by corporations. There is also the issue of dealing with international patent agreements. Indeed, that and the entrenched interests of firms that hold lots of valuable patents are probably the major forces that would block any such reform. That being said, implementation difficulties aside, it does seem possible that this would be a better system than the current practice of granting a time-limited monopoly on use to patent owners.

Macroeconomic calculations using water

On the New York Times website, there is a column about a water-based analog computer that was used to model the economy back in the 1950s:

Water flows through a series of clear pipes, mimicking the way that money flows through the economy. It lets you see (literally) what would happen if you lower tax rates or increase the money supply or whatever; just open a valve here or pull a lever there and the machine sloshes away, showing in real time how the water levels rise and fall in various tanks representing the growth in personal savings, tax revenue, and so on.

It’s both clever and amusing. Certainly, operating such a machine would have been less tedious than doing all the calculations with a pencil and paper. There is a video of the machine working on Cambridge University’s website.

Algae for biofuels?

One possible feedstock for biofuel production is algae, which could be grown and processed in various ways, producing transportation fuels. Some people seem to think this is the most plausible path to affordable non-fossil transportation fuels. Others think various land-based plants and processes (cellulosic ethanol, jatropha, etc) are more viable. Another big question is how cheap biofuels could ever become. Biofuels at $100 per barrel probably wouldn’t mean the end of air travel, private cars fueled by liquid hydrocarbons, etc. Biofuels at $1,000 a barrel would push us a lot father away from their mainstream use.

I don’t know enough to decide one way or the other, though it certainly doesn’t seem like anyone is making cheap and functional biofuels from algae right now.

Insultingly Stupid Movie Physics

Tom Roger’s Insultingly Stupid Movie Physics teaches basic science principles in one of the most entertaining ways possible: by illustrating the ways in which elements of popular Hollywood films are hopelessly out of line with the physical laws that exist in our universe. Topics covered include the laws of motion, gravitation, vehicles, the behaviour of weapons, relativity, extreme weather, space travel, and more.

While the book may seem whimsical, Rogers makes the important point that movies are a form of vicarious experience for people. For most of us, they have provided most of our ‘knowledge’ about firearms, knives, the extreme operation and destruction of vehicles, the destruction of buildings, etc. By consistently misrepresenting these things, films leave people ill-equipped to understand the phenomena in the real world.

In addition to this, Rogers’ book includes a detailed debunking of two conspiracy theories partially fuelled by a poor understanding of physics. In the first, he discusses the physics of the JFK assassination, in the context of the popular film. He argues that the official account is convincing for a number of reasons, and that the film has helped to entrench a serious misunderstanding in the minds of many Americans. The second conspiracy theory – that the World Trade Centre was destroyed using explosives planted inside – is similarly based in a bad understanding of physics, and similarly damaging in terms of the way in which it colours people’s thinking.

The kind of people who take delight in outsmarting the people who make movies will probably find this book very entertaining. Those trying to teach physics concepts may also find it useful as a mechanism for engaging people and having them explore ideas in an imaginative but realistic way.

Carnot efficiency

For a bit of light entertainment, I have been reading Tom Rogers’ book Insultingly Stupid Movie Physics, which basically covers the same terrain as his entertaining website, though at greater length and with more detail. Of course, one can never entirely escape climate change related information, and the book includes a discussion of Carnot efficiency: the maximum theoretical efficiency with which heat engines can convert thermal energy into useful power.

The efficiency depends on two factors: the high temperature produced using combustion, solar energy, geothermal energy, etc, and the cold temperature where the heat is expended into the surrounding environment:

Efficiency = ( 1 – Cold temperature / Hot temperature ) * 100

This has implications for technologies like the co-generation of heat and power. If the heat source for a power plant is 375°C (648°K) and it is dumping waste heat into 10°C (283°K) outdoor weather, the Carnot efficiency is about 56.3% (the actual efficiency is lower, for various reasons). If, instead, it is dumping the heat into buildings at 25°C (198°K), the Carnot efficiency falls to 54.0%. In a case where the heat source is just 200°C (473°K), the difference between a 10°C cold area and a 25°C cold area cuts the Carnot efficiency from 40.2% to 37.0%. In many cases, cogeneration is still worthwhile, despite the loss of useful electrical or kinetic energy, but it should be appreciated that the redirection is not without cost.

Carnot efficiency also helps explain why waste heat is not always worth capturing. If the temperature difference between the source and an available destination for the thermal energy is not large, there isn’t much useful power that can be produced.

[Update: 4:47pm] Remember to express the temperatures in Degrees Kelvin, by adding 273.15 to the figure in Degrees Celsius.