ENERGY: Nuclear power stations our safest option - Dr Dennis Jensen
by Joseph Poprzeczny and John Barich
News Weekly, August 19, 2006
Former CSIRO research scientist, Dr Dennis Jensen - currently Liberal federal MP for Tangney - delivered a lecture on nuclear energy in Perth. Joseph Poprzeczny was there with John Barich.
Ask anyone what they most fear when going for a swim at the beach and they'll invariably say it's the likelihood of being eaten by a shark.
Shark attacks are always newsworthy. Films featuring sharks, like Jaws, have a strange attraction.
Not widely realised, however, is that more Australians die from box jellyfish stings than from shark attacks.
The same quizzical phenomenon of fearing the lesser threat can be seen in the present and ongoing energy controversy, according to Western Australian Liberal MHR, Dr Dennis Jensen, a former CSIRO research scientist.
Delivering a Council of the National Interest special lecture on energy in Perth, he outlined how provision of nuclear-generated electricity was far and away the safest option.
He demonstrated this point by focusing upon a huge unit of measure known as the terawatt year.
Now, the terawatt is best comprehended by firstly defining the watt - named after the Scottish engineer James Watt (1736-1819) - as a unit of power that equals one joule of energy per second.
To get to the terawatt one firstly multiplies a watt by 1,000 which is a kilowatt. Next multiply that kilowatt by another 1,000 and you have a megawatt. Now, if you multiply the megawatt by another 1,000 you have a gigawatt. To attain a terawatt you must multiply this gigawatt by yet another 1,000.
What this means is that the terawatt you now have is a trillion - one followed by 12 zeros - watts.
When grappling with all these zeros, keep at the forefront of your mind that a 500-megawatt power station is considered worldwide as a sizeable base-load generating unit.
Consequently, a station whose output was one terawatt would be equivalent to 2,000 such 500-megawatt stations, something that does not exist anywhere in the world.
Dr Jensen said that engineers and statisticians used the output of one terawatt of power over a year as a unit to compare the safety levels of different types of power stations - coal-fired, hydro-generation, gas fired, LPG and nuclear.
He said: "I'll quote figures in terms of normalised deaths per terawatt year. In other words, if you generate one terawatt of energy for one calendar year, how many deaths can you expect in the industry?"
"For coal-fired power stations, there are 342 fatalities per terawatt year which are predominantly related to coal-workers actually extracting the coal.
"However, this number would be far worse if the figures where there were fewer than five fatalities per incident were included.
"With oil, it is 418 fatalities per terawatt year.
"With natural gas, it is somewhat lower - 85 fatalities per terawatt year, and this refers to workers as well as the public.
"Incidentally, LPG-related fatalities are extremely high - 3,280 per terawatt year of electricity generated.
"With hydro-electricity - a method that some opponents of nuclear energy favour while some dislike - there are 883 fatalities per terawatt year which predominantly involves the public due to collapsing dams.
"Now we come to nuclear energy, with 31 fatalities per terawatt year. This is the lowest of all electricity-generation methods."
Dr Jensen said this low fatality figure included Chernobyl's deaths and fatalities in the mining of uranium.
"I know some people might like to point to Chernobyl," he said.
"According to the OECD, there have been 56 fatalities as a result of Chernobyl, due to thyroid cancer and the immediate deaths of the workers at the time - the major medical problem was radiation exposure.
"The problem with Chernobyl, apart from anything else, was that it had inadequate containment.
"But, as can be seen, nuclear energy is actually a very safe option - and it's inherently safer these days with Generation IV reactors.
"Western containment has been far better.
"Regarding safety, nuclear power is demonstrably the safest form of power generation.
"Consider the thousands of annual coalmining deaths and the probable millions who have died as a result of respiratory ailments due to coal-fired power," Mr Jensen said.
"Consider the fatalities resulting from gas or hydroelectricity production, and it becomes clear that nuclear energy is very safe, even when you look at the history and take into account a sub-standard Soviet RBMK reactor."
He said he believed Australia could use Generation IV reactors, which are inherently safe.
"These reactors cannot melt down because of the physics of the design of the reactor, not due to fail-safes appended to provide safety," he continued.
"Most Generation IV reactors also don't need enriched uranium, so reserves of uranium would last about 50 times as long as it's assumed they will last for conventional reactors.
"It is significant that Generation IV reactors, which will be modular in design, will allow small reactors to power smaller population centres and multiple modules to be joined together at the site of larger power demand.
"The economic side is put by some as a criticism. In fact, when you look at what is being considered, the economic argument is not a strong one.
"What Parliament needs to consider is whether to legislate to allow nuclear power generation.
"Economics should be left to power utilities which choose whether to use it or not.
"Interestingly, the fact that many nuclear opponents push this line so strongly indicates that they are concerned that the economics of nuclear energy do stack up."
Dr Jensen's doctoral thesis was on high temperature tough zirconia ceramic material.
He has been a CSIRO scientist and research scientist and defence analyst working on submarine operations research.