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producing energy, hydraulic, tidal, solar, and nuclear, and is sufficient reason by itself to stop any further fossil-fired power stations to be built for the supply of Hong Kong's electricity.
Opponents of nuclear energy often mention other alternatives: Fusion instead of fission, solar, wind, tidal. All these are being worked on: Fusion for more than 40 years and we are no nearer to it now than we were when we first started. Solar for over 50 years and no-one has yet come up with a practical way of converting the sun's rays into large-scale electricity (small-scale electricity is being obtained in many countries, with Israel being the most advanced, and the Hong Kong Government are as remiss in this field as they are in the field of environmental pollution, in that they have never really pushed any attempts at including solar power supplies into our housing estates for hot water, heat, and, possibly, air conditioning). Wind needs a great deal of land and is very noisy and also does not produce any large quantities of energy, and tidal has geographical limitations which will never be overcome. So, for the foreseeable future, if we don't want to cause a global catastrophe by heating up the atmosphere, or lots of sickness by polluting the air, we are stuck with nuclear energy.
One of the reasons why I wanted to wait some time before making this speech was to try and get rather more information than was available in the first month after the accident.
Piecing together all the more responsible newspaper reports, the official Tass press statements, the actions taken by the Russian Authorities, etc., a picture emerges which is really a commentary on human failing. Chernobyl before the accident was one of the prides of the Soviet Nuclear Energy Programme because it was by far the cheapest of all the stations built in the Soviet Union. It had been pared down, even to the extent that the containment building (and there was a containment building) was sufficiently strong only to contain minor accidents, which were all the Soviet experts expected might happen. Automatic safety shutdown mechanisms had been left out. In other words, the main money-saving was at the expense of safety. Now, one has to remember that the Soviet experts have a great deal of experience; they are not stupid; they were taking calculated risks, and in the normal course of events, their calculated risks would have been perfectly acceptable. What was left out, however, was unaccountable human stupidity. No-one in their right mind could have expected that some minor functionary would decide to run an experiment in a nuclear power plant that had not been authorized by any scientific or administrative committee, that was apparently an attempt at self-glorification by someone quite low on the totem-pole, and which was compounded by bureaucratic irresponsibility inherent in the Communist system. No-one was ready to take responsibility or make sure laid-down safety procedures were complied with. The personnel concerned were obviously lazy, uneducated, and completely unreliable.
We are now assured that this sort of thing cannot happen here, but we are dealing with a similar political system, and similar political systems often
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produce similar situations, especially when you get a non-expert running a highly technical industry simply because he is politically reliable (just to make sure that everybody understands, I am not simply blaming the Communist system. Three Mile Island showed a similar syndrome under a Capitalist system and produced a similar result for very different economic reasons).
What this all boils down to is that Murphy's Law will operate, that in any calculations we make about risks, whether this be the risk of driving a motor car, or taking an aeroplane, or going to hospital and letting a surgeon operate, or running a nuclear power station, human stupidity must be taken into the calculation as a major factor. What we really want is something that is fail-safe, so that even human stupidity cannot cause an accident. Now, it so happens that way back in 1956, Dr. Edward Teller, the inventor of the hydrogen bomb, sat down to design a nuclear reactor safe enough for a party of school children to play with, and he and his colleagues did design a safe reactor called the 'Triga'. General Atomic, a subsidiary of General Dynamics, actually built such a reactor, and at the dedication ceremony, the very famous physicist, Niels Bohr, put the 'Triga' through a party trick. He pressed the switch that pulled all the control rods out of the core at high speed, which should have caused a catastrophic accident. For a few thousandths of a second, the output of the reactor soared, and then it brought itself under control. The 'Triga' proved itself to be inherently safe.
All existing commercial reactors rely on engineered safety: The use of active devices that detect and then respond to danger. For example, if a reactor core overheats, cooling water is supposed to flood in to prevent a meltdown. At Three Mile Island and Chernobyl, these systems fell foul of Murphy's Law: If something can go wrong, it will. The idea must be to replace Murphy's Law with the laws of physics. The law of physics exploited by the 'Triga' is that warm neutrons are less effective than cold ones in causing atoms to split. The neutrons in a water-cooled reactor are slowed down by collision with hydrogen atoms in the water. Had Mr. Bohr pulled the control rods from an ordinary reactor, the fuel would have warmed up, but the cooling water would have stayed cold. That means the neutrons would stay cold, and fission would continue. But in the 'Triga', only half the hydrogen atoms are in the cooling water, and the other half are in the control rods, so when the fuel rods heat up, so do half the hydrogen atoms. The warm neutrons cause less fission and escape faster into the cooling water. By warming up, a 'Triga' starts the very process that cools the reactor down.
Unfortunately, the biggest 'Triga' ever built was a tiny 10 megawatts, suitable for research rather than for commercial power generation, and for economic reasons, inherent safety never caught on for the bigger reactors: It was too expensive. But now that engineered safety is becoming extremely expensive, it is time to go back to designing a commercial reactor with inherent safety built in, because the economic penalties for this inherent safety have now disappeared. I understand that there are at least two large American companies working on the
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288
HONG KONG URBAN COUNCIL
producing energy, hydraulic, tidal, solar, and nuclear, and is sufficient reason by itself to stop any further fossil fired power stations to be built for the supply of Hong Kong's electricity.
Opponents of nuclear energy often mention other alternatives: Fusion instead of fission, solar, wind, tidal. All these are being worked on: Fusion for more than 40 years and we are no nearer to it now than we were when we first started, Solar for over 50 years and no-one has yet come up with a practical way of converting the sun's rays into large scale electricity (small scale electricity is being obtained in many countries with Israel being the most advanced and the Hong Kong Government are as remiss in this field as they are in the field of environmental pollution in that they have never really pushed any attempts at including solar power supplies into our housing estates for hot water, heat and, possibly, air conditioning). Wind needs a great deal of land and is very noisy and also does not produce any large quantities of energy, and tidal has geographical limitations which will never be overcome. So, for the foreseeable future, if we don't want to cause a global catastrophe by heating up the atmosphere, or lots of sickness by polluting the air, we are stuck with nuclear energy.
One of the reasons why I wanted to wait some time AC before making this speech was to try and get rather more information than was available in the first month after the accident.
Piecing together all the more responsible newspaper reports, the official Tass press statements, the actions taken by the Russian Authorities etc. etc. a picture emerges which is really a commentary on human failing. Chernobyl before the accident was one of the prides of the Soviet Nuclear Energy Programme because it was by far the cheapest of all the stations built in the Soviet Union. It had been pared down even to the extent that the containment building (and there was a containment building) was sufficiently strong only to contain minor accidents which were all the Soviet experts expected might happen. Automatic safety shutdown mechanisms had been left out. In other words, the main money saving was at the expense of safety. Now one has to remember that the Soviet experts have a great deal of experience, they are not stupid, they were taking calculated risks, and in the normal course of events their calculated risks would have been perfectly. acceptable. What was left out, however, was unaccountable human stupidity. No-one in their right mind could have expected that some minor functionary would decide to run an experiment in a nuclear power plant that had not been authorized by any scientific or administration committee, that was apparently an attempt at self-glorification by someone quite low on the totem-pole and which was compounded by bureaucratic irresponsibility inherent in the Communist system. No-one was ready to take responsibility or make sure laid down safety procedures were complied with. The personnel concerned was obviously lazy, uneducated and completely unreliable.
We are now assured that this sort of thing cannot happen here, but we are dealing with a similar political system and similar political systems often
HONG KONG URBAN COUNCIL
Page 165 of 201
289
produce similar situations, especially when you get a non-expert running a highly technical industry simply because he is politically reliable (just to make sure that everybody understands, I am not simply blaming the Communist system. Three Mile Island showed a similar syndrome under a Capitalist system and produced a similar result for very different economic reasons).
What this all boils down to is that Murphy's Law will operate, that in any calculations we make about risks whether this be the risk of driving a motor car, or taking an aeroplane, or of going to hospital and letting a surgeon operate, or running a nuclear power station, human stupidity must be taken into the calculation as a major factor. What we really want is something that is fail safe, so that even human stupidity cannot cause an accident. Now it so happens that way back in 1956 Dr. Edward TELLER, the inventor of the hydrogen bomb, sat down to design a nuclear reactor safe enough for a party of school children to play with and he and his colleagues did design a safe reactor called the 'Triga'. General Atomic, a subsidiary of General Dynamics, actually built such a reactor and at the dedication ceremony the very famous physicist, Niels BOHR, put the 'Triga' through a party trick. He pressed the switch that pulled all the control rods out of the core at high speed which should have caused a catastrophic accident. For a few thousands of a second the output of the reactor soard and then it brought itself under control. The 'Triga' proved itself to be inherently safe.
All existing commercial reactors rely on engineered safety: The use of active devices that detect and then respond to danger. For example, if a reactor core overheats, cooling water is supposed to flood in to prevent a melt down. At Three Mile Island and Chernobyl these systems fell foul of Murphy's Law: If something can go wrong, it will. The idea must be to replace Murphy's Law with the laws of physics. The law of physics exploited by the ‘Triga' is that warm neutrons are less effective than cold ones in causing atoms to split. The neutrons in a water cooled reactor are slowed down by collision with hydrogen atoms in the water. Had Mr. BOHR plucked the control rods from an ordinary reactor the fuel would have warmed up but the cooling water would have stayed cold. That means the neutrons would stay cold and fission would continue. But in the 'Triga' only half the hydrogen atoms are in the cooling water and the other half are in the control rods so when the fuel rods heat up so do half the hydrogen atoms. The warm neutrons cause less fission and escape faster into the cooling water. By warming up a "Triga' starts the very process that cools the reactor down.
Unfortunately, the biggest 'Triga' ever built was a tiny 10 megawatts suitable for research rather than for commercial power generation, and for economic reasons inherent safety never caught on for the bigger reactors: It was too expensive. But now that engineered safety is becoming extremely expensive it is time to go back to designing a commercial reactor with inherent safety built in because the economic penalties for this inherent safety have now disappeared. I understand that there are at least two large American companies working on the
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