Well it’s an overused word right now but have a look at this if you’ve not seen it before – it’s lovely.
Awesome
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Category Archives: Science
Nuclear madness in Idaho
When the SL-1 nuclear reactor exploded in Idaho releasing a radioactive plume and killing three workers, a local paper reported the accident on page 12. That was 1961. Today some residents of Idaho are so worried about the nuclear accident 8000 kilometers away that they’re buying potassium iodide pills.
According to a history by Susan Stacey: "Editorial comment in Idaho and other newspapers categorized the SL-1 accident as a regrettable mishap, an inevitable occurrence if society were to accrue the benefits of a new technology." Today experts argue about whether the thick concrete containment around Fukushima Daiichi’s reactor vessel is safe enough and residents of inland American states worry about nuclear radiation from the accident. But the low-powered SL-1 boiling water reactor in Idaho had no containment. It was designed to be light weight — a prototype for reactors that could be shipped to the Arctic Circle to power remote military radar stations (pdf).
During the 1950s the US military looked to nuclear power as a practical way to solve problems. One problem was how to extend the range of its bombers. It sounds outrageous today, but the air force had plans to power aircraft using nuclear reactors. As a General Electric engineer, told Congress, a nuclear powered aircraft would be "limited in range only by sandwiches and coffee for the crew".
General Electric was one of a number of contractors engaged on the military’s aircraft nuclear propulsion program. At the National Reactor Testing Station (NRTS) in Idaho, GE’s engineers tested a nuclear power plant that sucked air directly into the reactor with the exhaust streaming out of a pair of specially modified jet engines. To test this ‘direct cycle’ engine, GE needed an outdoor test pad. According to Stacey:
Contaminated air could not be allowed to blow out the nozzle indoors—or near work areas. Rather, the reactor-cum-engine traveled back and forth between an assembly area and the test pad, a distance of a mile and a half. A man driving a shielded locomotive hauled a dolly carrying the eighty-ton assembly on four-rail tracks. At the test pad, the engine connected to a "coupling station"where the exhaust was filtered, went up a 150-foot stack, and was released to the open air (pdf).
Seeking alternatives to nuclear and fossil fuels
The latest situation with damaged Japanese nuclear power plants seems if anything more potentially dire and apocalyptic than what prompted my comment on Don Arthur’s post:
Seems to me that whatever now happens the nuclear power option is almost certainly a dead duck in all western nations with free media. Whatever may be the wholly utilitarian risk/benefit analysis, the images and sense of Armageddon we’re seeing coming out of Japan will be imprinted on people’s minds permanently, meaning that politicians from now on simply won’t be able to propose nuclear power solutions without facing terminal electoral consequences.
The images coming out of Japan mean that it’s game, set and match to the Greens on the nuke power issue and we need to get on and develop other sustainable, low carbon baseload power options.
However, it appears that currently feasible non-nuclear and non-fossil fuel baseload power options (i.e. commercially deployable in the near future) are by no means obvious.
Nuclear pebble bed reactors seemed to hold some hope of cheaper nuclear options that didn’t carry the risk of overheating and meltdown so evident in Japan. However, trial reactor programs have largely been abandoned as unpromising.
Hydrogen fuel is fraught with problems that haven’t been solved, mostly related to its volatility, lightness and very low energy/volume ratio. Compressing or liquefying it are both extraordinarily expensive.
Solar thermal might be capable of development to something approaching baseload constant availability with storage of energy generated during the day (e.g. superheated water) but certainly isn’t ready to be deployed on a large scale. Moreover cost appears almost prohibitive:
Due to the nature of technology and the electricity market, says BZE, the carbon price would need to be above $70 a tonne before it could begin to have benefits for any new form of renewable energy generation. Between $70 and $200 a tonne, the signal is for extra growth in wind power combined with (what Wright calls) ”fossil gas”. More than $200 a tonne is needed to make baseload solar thermal viable at current prices.
“Clean coal” is almost certainly an expensive fantasy at least in most parts of the world, because very large underground storage caverns for the Co2 extracted to make “clean” coal just don’t exist.
So what else is there? I’d be most interested in readers’ thoughts.
I note that the Green lobby is arguing that you really don’t need any baseload power sources at all, and that enough continuous electricity can be delivered by a patchwork of renewable but non-continuous sources, perhaps supplemented occasionally by reserve LNG plants. Mark Diesendorff is a leading local proponent of that approach, and a retired scientist Dr David Mills claims that the US could meet all its current electricity needs with such a patchwork approach and without relying on either nuclear or fossil fuels. Somehow I have my doubts, but again I’d be interested in readers’ thoughts (especially those with some relevant knowledge/expertise).
Background on Japan’s stricken nuclear reactor — Fukushima Daiichi No 1
According to recent media reports an explosion has blown the roof off an unstable reactor north of Tokyo. The reactor is Fukushima Daiichi nuclear power station’s unit no 1. World Nuclear News reports:
Television cameras trained on the plant captured a dramatic explosion surrounding unit 1 at around 6pm. Amid a visible pressure release and a cloud of dust it was not possible to know the extent of the damage. The external building structure does not act as the containment, which is an airtight engineered boundary within. The status of the containment is not yet known.
Here’s some background on Fukushima Daiichi and the events leading up to the incident.
Number of reactors: The Fukushima Daiichi nuclear power station has six reactors. According to the Tokyo Electric Power Company (Tepco), when the quake hit three of the reactors were shut down for periodic inspection (units 4, 5 and 6). The other three (1, 2 and 3) were shut down in response to the quake.
Type of reactor: The reactors at Fukushima Daiichi are boiling water reactors (see diagram below).
According to the US Energy Information Administration:
In a typical commercial boiling water reactor the reactor core creates heat, a steam-water mixture is produced when very pure water (reactor coolant) moves upward through the core absorbing heat, the steam-water mixture leaves the top of the core and enters the two stages of moisture separation where water droplets are removed before the steam is allowed to enter the steam line, the steam line directs the steam to the main turbine causing it to turn the turbine generator, which produces electricity. The unused steam is exhausted to the condenser where it is condensed into water. The resulting water is pumped out of the condenser with a series of pumps, reheated, and pumped back to the reactor vessel. The reactor’s core contains fuel assemblies which are cooled by water, which is force-circulated by electrically powered pumps. Emergency cooling water is supplied by other pumps which can be powered by onsite diesel generators. Other safety systems, such as the containment cooling system, also need electric power.
What caused the problem?: After a reactor is shut down it needs to be cooled. According to Ron Chesser, director for the Center of Environmental Radiation Studies at Texas Tech University:
Unpacking the Yasi hype
* Below is a guest post written by Ken G, a long-time Darwin resident and media/IT professional. Ken discussed his ideas not only with Darwin “storm chaser” enthusiasts but with Darwin residents who went through Cyclone Tracy. It’s a keen amateur perspective on a frightening weather event but well worth reading in my opinion.
Cyclone Yasi was a big and scarey storm system. Media and politicians continue to refer to it as a Category 5 cyclone with winds nearing 300 kmh near its centre, the largest cyclone ever to hit a populated area in Australia. But is that really true? A fairly obscure story on Australian Geographic website points out that “the full force may never be known because there are no gauges where the monster storm made landfall” and an engineer interviewed on last Friday’s 7:30 Report suggested that available data indicated Yasi was probably a small to medium Category 4 system with winds a bit over 200 kmh. But that’s just about the full extent of any questioning of Yasi’s actual strength and destructive force. What does the evidence actually tell us?
Don’t get me wrong; it did seem like it was going to be a very large event and government authorities were well justified in taking the steps they did to encourage residents to take it very seriously. Looking at the Bureau of Meteorology site and at the radar images you could see this was a very nasty storm that was going to hit the coast. Moreover, even if it WAS “only” a small-medium Category 4 cyclone that’s still a very large storm with frightening and lethal destructive force.
National Broadband Network under the microscope
I’m seriously conflicted by the debate over Labor’s National Broadband Network.
On one hand, the future of CDU’s online Bachelor of Laws programs, whose creation and development I oversee, is heavily dependent on the availability of almost universal truly fast broadband within the next few years. The policy that the federal Coalition took to the last election just doesn’t cut the mustard and would if implemented effectively stymie our plans and possibly the long-term viability of the law school itself.
Indeed it would imperil federal government plans to expand the scope of higher education to cover double the number of Australians presently studying by 2020. That can only be achieved if people can study effectively using powerful flexible learning technologies which allow them to study from home or the workplace rather than needing to traipse to a university campus after work.
On the other hand, I think Labor’s current NBN policy is seriously wasteful and dangerously extravagant. An adequate fast broadband policy could certainly be fashioned which would cost much less than Labor’s plan but deliver reliable fast broadband to a much greater proportion of Australia’s population than the Coalition’s badly flawed ideas. Let me explain.
Sydney Uni book fair
Saturday 11 to Wed 15, 10 am to 5 in the Great Hall.
My treasures: all in practically “as new” condition.
Peter Medawar, Pluto’s Republic (not a missprint). $3. Review. The editor of the Age Monthly Review would not let me write that the cover photo depicted Medwar demonstrating how he held the ball for his off-break.
John J Ray, Conservatism as Heresy (1974). $2. An absolute classic! Many years ahead of its time. You can read it all on line at John Ray’s website.
The chapter on the 1974 election is a surprise.
Sunset on the moon
