Nuclear: back on the horizon
Nuclear: back on the horizon - National - theage.com.au
Faced with a mounting climate crisis, some green advocates are embracing a radical solution - nuclear energy. But perhaps another answer lies under the ground. By Tim Flannery.
IT’S OFTEN said that the sun is nuclear energy at a safe distance. In this era of climate crisis, however, the role of earth-based nuclear power is being reassessed, and what was until recently a dying technology may yet create its own day in the sun.
The revival began in earnest in May 2004, when environmental organisations around the world were shocked to hear the eminent British scientist, James Lovelock, deliver a heartfelt plea for a massive expansion in the world’s nuclear energy programs. Lovelock did so, he said, because he believed that climate change was advancing so rapidly that nuclear power was the only option available to stop it. He compared our present situation with that of the world in 1938 — on the brink of war and nobody knowing what to do. Organisations such as Greenpeace and Friends of the Earth immediately rejected his call.
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AdvertisementYet Lovelock has a point, for all power grids need reliable “baseload” generation, and there remains a big question mark over the capacity of renewable technologies to provide it. France supplies nearly 80 per cent of its power from nuclear sources, while Sweden provides half and the UK one quarter. Nuclear power already provides 18 per cent of the world’s electricity, with no CO2 emissions. Its proponents argue that it could supply far more, but even the Bush Administration’s energy forecasters believe that its share will in fact fall — to just 10 per cent of production — within the next decade.
As with coal, nuclear power stations are very large and, with a starting price of around $US2 billion ($A2.59 billion) apiece, they are expensive to build. The power they generate, however, is at present competitive with that generated from wind. Because they are large, and many factors relating to safety must be considered, the permitting process for a nuclear power station can take up to a decade, with construction taking around five years. With a 15- year gestation period before any power is generated, and even longer before any return on the investment is seen, nuclear power is not for the impatient investor. It is this, as much as concerns about safety, which explains why no new reactors have been built for 20 years in either the US or UK.
Three factors loom large in the mind of the public, however, whenever nuclear power is mentioned — safety, disposal of waste and bombs. The horror of the 1986 Chernobyl disaster in Ukraine was a catastrophe of stupendous proportions whose consequences, two decades after the accident, just keep growing. Thyroid cancer is a rare illness, with just one in a million children developing it spontaneously. But one-third of children under four years old who were exposed to fallout from Chernobyl will develop the disease. Seven per cent (about 3.3 million people) of the population of Ukraine have suffered illness as a result of the meltdown, while in neighbouring Belarus, which received 70 per cent of the fallout, the situation is even worse. Only 1 per cent of the country is free from contamination, 25 per cent of its farmland has been put permanently out of production, and nearly 1000 children die each year from thyroid cancer. Currently, 25 per cent of the Belarus budget is spent on alleviating the effects of the disaster.
In the US and Europe, safer reactor types predominate but, as the Three Mile Island incident shows, no one is immune to accident, or to sabotage.
With several nuclear reactors in the US located near large cities, there are real concerns for a possible terrorist attack. In summarising the situation for nuclear power as it stood in late 2004, the US National Commission on Energy Policy said, “One would want the probability of a major release of radioactivity, measured per reactor per year, to fall a further tenfold or more (before considering a doubling or tripling of nuclear power capacity). This means improved defences against terrorist attack as well as against malfunction or human error.” The management of radioactive waste is another issue of concern. The nuclear industry in the US long looked to the proposed high-level radioactive waste dump at Yucca Mountain, Nevada, as a solution. But the waste stream has now reached such proportions that even if Yucca Mountain were opened tomorrow it would be filled at once and another dump would be needed. In reality, the opening of the Yucca Mountain dump looks to be delayed for years as challenges drag on through the courts.
And the problem of what to do with old and obsolete nuclear power plants is almost as intractable: the US has 103 nuclear plants that were originally licensed to operate for 30 years, but are now slated to grind on for double that time. This ageing fleet must be giving the industry headaches, especially as no reactor has ever yet been successfully dismantled, perhaps because the cost is estimated to be around $500 million a pop.
The majority of new nuclear power plants are being built in the developing world, where a less tight-laced bureaucracy and greater central control makes things easier. China will commission two new nuclear power stations per year for the next 20 years, which from a global perspective is highly desirable, for 80 per cent of China’s power now comes from coal. India, Russia, Japan and Canada also have reactors under construction, while approvals are in place for 37 more in Brazil, Iran, India, Pakistan, South Korea, Finland and Japan. Providing the uranium necessary to fuel these reactors will be a challenge, for world uranium reserves are not large, and at the moment around a quarter of the world’s demand is being met by reprocessing redundant nuclear weapons. This brings us to the issue of nuclear weapons getting into the wrong hands. As the current dispute over the proposed Iranian reactor indicates, anyone who possesses enriched uranium has the potential to create a bomb. As reactors proliferate and alliances shift, there is an increasing likelihood that such weapons will be available to those who want them.
The nuclear industry hopes that technological developments will lead to foolproof reactor types that produce electricity at a cost equivalent to coal. New reactor types include pebble bed reactors, which utilise low-enriched uranium and can be built on a smaller scale than conventional plants, and pressurised water reactors, one of which will soon be built in Normandy, France, which promises to produce power more cheaply than coal. As with geosequestration, however, these are technologies for the future.
What role might nuclear power play in averting the climate change disaster? China and India are likely to pursue the nuclear option with vigour, for there is currently no inexpensive, large-scale alternative available to them. Both nations already have nuclear weapons programs, so the relative risk of proliferation is not great. In the developed world, though, any major expansion of nuclear power will depend upon the viability of new, safer reactor types.
There is one other option for the continuous production of power. Geothermal energy has a long history, yet despite the considerable amount of heat lying between our feet and our planet’s molten mantle, geothermal technologies provide a mere 10,000 megawatts of power worldwide.
This sorry state of affairs may soon change, for it now transpires that we have been looking for heat in the wrong places. Previously geothermal power has come from volcanic regions, where aquifers flowing through the hot rocks provide superheated water and steam.
In Switzerland and Australia, companies are finding commercially usable heat in the most unlikely places. When oil and gas companies prospected in the deserts of northern South Australia, nearly four kilometres below the surface, they discovered a body of granite heated to around 250 degrees — the hottest near-surface, non-volcanic rock ever discovered.
The heat had been generated by the natural radioactivity of the granite, which had been kept in place by a blanket of sediment nearly four kilometres thick. What really excited the geologists was that the granite was not in a region where the earth’s crust was being torn apart, but where it was being compressed. This led to horizontal, rather than vertical fracturing of the rock. Even better, the rocks are bathed in superheated water under great pressure, and the horizontal fracturing meant that it could be readily recycled.
This one rock body in South Australia is estimated to contain enough heat to supply all of Australia’s power needs for 75 years, at a cost equivalent to that of brown coal, without the CO2 emissions.
With trial power plants scheduled for construction soon, the enormous potential of geothermal power is about to be tested. Geologists around the world are scrambling to prospect for similar deposits, as the extent of the resource is hardly known. There is some reason to believe, however, that Australia may be specially blessed with this type of potential power, for the continent has been moving northwards at around eight centimetres per year for the past 40 million years, and when it bumped into Asia 15 million years ago, enormous compressional forces were generated. As a result, in Australian mines one kilometre deep, engineers must deal with compressional forces encountered five kilometres down in places such as South Africa. While this appears to be an exciting breakthrough, we must remember that so far very little electricity has been provided by this form of geothermal heat, and even if successful, it will in all likelihood be decades before this technology is contributing significantly to the world grid.
Humanity is at a great crossroads. Trillions of dollars will need to be invested to make the transition to the carbon-free economy and, once a certain path of investment is embarked upon, it will gather such momentum that it will be difficult to change direction. So what might life be like if we choose one over the other? In the hydrogen and nuclear economies the production of power is likely to be centralised, which would mean the survival of the big power corporations. Pursuing wind and solar technologies, on the other hand, opens the possibility that people will generate most of their own power, transport fuel and even water (by condensing it from the air).
If we follow this second path, we will have opened a door to a world the likes of which have not been seen since the days of James Watt, when a single fuel powered transport, industrial and domestic needs alike, the big difference being that the fuel will be generated not by large corporations, but by every one of us.
This is an edited extract from THE WEATHER MAKERS: The History and Future Impact of Climate Change, by Tim Flannery. Text Publishing, $32.95
Faced with a mounting climate crisis, some green advocates are embracing a radical solution - nuclear energy. But perhaps another answer lies under the ground. By Tim Flannery.
IT’S OFTEN said that the sun is nuclear energy at a safe distance. In this era of climate crisis, however, the role of earth-based nuclear power is being reassessed, and what was until recently a dying technology may yet create its own day in the sun.
The revival began in earnest in May 2004, when environmental organisations around the world were shocked to hear the eminent British scientist, James Lovelock, deliver a heartfelt plea for a massive expansion in the world’s nuclear energy programs. Lovelock did so, he said, because he believed that climate change was advancing so rapidly that nuclear power was the only option available to stop it. He compared our present situation with that of the world in 1938 — on the brink of war and nobody knowing what to do. Organisations such as Greenpeace and Friends of the Earth immediately rejected his call.
Advertisement
AdvertisementYet Lovelock has a point, for all power grids need reliable “baseload” generation, and there remains a big question mark over the capacity of renewable technologies to provide it. France supplies nearly 80 per cent of its power from nuclear sources, while Sweden provides half and the UK one quarter. Nuclear power already provides 18 per cent of the world’s electricity, with no CO2 emissions. Its proponents argue that it could supply far more, but even the Bush Administration’s energy forecasters believe that its share will in fact fall — to just 10 per cent of production — within the next decade.
As with coal, nuclear power stations are very large and, with a starting price of around $US2 billion ($A2.59 billion) apiece, they are expensive to build. The power they generate, however, is at present competitive with that generated from wind. Because they are large, and many factors relating to safety must be considered, the permitting process for a nuclear power station can take up to a decade, with construction taking around five years. With a 15- year gestation period before any power is generated, and even longer before any return on the investment is seen, nuclear power is not for the impatient investor. It is this, as much as concerns about safety, which explains why no new reactors have been built for 20 years in either the US or UK.
Three factors loom large in the mind of the public, however, whenever nuclear power is mentioned — safety, disposal of waste and bombs. The horror of the 1986 Chernobyl disaster in Ukraine was a catastrophe of stupendous proportions whose consequences, two decades after the accident, just keep growing. Thyroid cancer is a rare illness, with just one in a million children developing it spontaneously. But one-third of children under four years old who were exposed to fallout from Chernobyl will develop the disease. Seven per cent (about 3.3 million people) of the population of Ukraine have suffered illness as a result of the meltdown, while in neighbouring Belarus, which received 70 per cent of the fallout, the situation is even worse. Only 1 per cent of the country is free from contamination, 25 per cent of its farmland has been put permanently out of production, and nearly 1000 children die each year from thyroid cancer. Currently, 25 per cent of the Belarus budget is spent on alleviating the effects of the disaster.
In the US and Europe, safer reactor types predominate but, as the Three Mile Island incident shows, no one is immune to accident, or to sabotage.
With several nuclear reactors in the US located near large cities, there are real concerns for a possible terrorist attack. In summarising the situation for nuclear power as it stood in late 2004, the US National Commission on Energy Policy said, “One would want the probability of a major release of radioactivity, measured per reactor per year, to fall a further tenfold or more (before considering a doubling or tripling of nuclear power capacity). This means improved defences against terrorist attack as well as against malfunction or human error.” The management of radioactive waste is another issue of concern. The nuclear industry in the US long looked to the proposed high-level radioactive waste dump at Yucca Mountain, Nevada, as a solution. But the waste stream has now reached such proportions that even if Yucca Mountain were opened tomorrow it would be filled at once and another dump would be needed. In reality, the opening of the Yucca Mountain dump looks to be delayed for years as challenges drag on through the courts.
And the problem of what to do with old and obsolete nuclear power plants is almost as intractable: the US has 103 nuclear plants that were originally licensed to operate for 30 years, but are now slated to grind on for double that time. This ageing fleet must be giving the industry headaches, especially as no reactor has ever yet been successfully dismantled, perhaps because the cost is estimated to be around $500 million a pop.
The majority of new nuclear power plants are being built in the developing world, where a less tight-laced bureaucracy and greater central control makes things easier. China will commission two new nuclear power stations per year for the next 20 years, which from a global perspective is highly desirable, for 80 per cent of China’s power now comes from coal. India, Russia, Japan and Canada also have reactors under construction, while approvals are in place for 37 more in Brazil, Iran, India, Pakistan, South Korea, Finland and Japan. Providing the uranium necessary to fuel these reactors will be a challenge, for world uranium reserves are not large, and at the moment around a quarter of the world’s demand is being met by reprocessing redundant nuclear weapons. This brings us to the issue of nuclear weapons getting into the wrong hands. As the current dispute over the proposed Iranian reactor indicates, anyone who possesses enriched uranium has the potential to create a bomb. As reactors proliferate and alliances shift, there is an increasing likelihood that such weapons will be available to those who want them.
The nuclear industry hopes that technological developments will lead to foolproof reactor types that produce electricity at a cost equivalent to coal. New reactor types include pebble bed reactors, which utilise low-enriched uranium and can be built on a smaller scale than conventional plants, and pressurised water reactors, one of which will soon be built in Normandy, France, which promises to produce power more cheaply than coal. As with geosequestration, however, these are technologies for the future.
What role might nuclear power play in averting the climate change disaster? China and India are likely to pursue the nuclear option with vigour, for there is currently no inexpensive, large-scale alternative available to them. Both nations already have nuclear weapons programs, so the relative risk of proliferation is not great. In the developed world, though, any major expansion of nuclear power will depend upon the viability of new, safer reactor types.
There is one other option for the continuous production of power. Geothermal energy has a long history, yet despite the considerable amount of heat lying between our feet and our planet’s molten mantle, geothermal technologies provide a mere 10,000 megawatts of power worldwide.
This sorry state of affairs may soon change, for it now transpires that we have been looking for heat in the wrong places. Previously geothermal power has come from volcanic regions, where aquifers flowing through the hot rocks provide superheated water and steam.
In Switzerland and Australia, companies are finding commercially usable heat in the most unlikely places. When oil and gas companies prospected in the deserts of northern South Australia, nearly four kilometres below the surface, they discovered a body of granite heated to around 250 degrees — the hottest near-surface, non-volcanic rock ever discovered.
The heat had been generated by the natural radioactivity of the granite, which had been kept in place by a blanket of sediment nearly four kilometres thick. What really excited the geologists was that the granite was not in a region where the earth’s crust was being torn apart, but where it was being compressed. This led to horizontal, rather than vertical fracturing of the rock. Even better, the rocks are bathed in superheated water under great pressure, and the horizontal fracturing meant that it could be readily recycled.
This one rock body in South Australia is estimated to contain enough heat to supply all of Australia’s power needs for 75 years, at a cost equivalent to that of brown coal, without the CO2 emissions.
With trial power plants scheduled for construction soon, the enormous potential of geothermal power is about to be tested. Geologists around the world are scrambling to prospect for similar deposits, as the extent of the resource is hardly known. There is some reason to believe, however, that Australia may be specially blessed with this type of potential power, for the continent has been moving northwards at around eight centimetres per year for the past 40 million years, and when it bumped into Asia 15 million years ago, enormous compressional forces were generated. As a result, in Australian mines one kilometre deep, engineers must deal with compressional forces encountered five kilometres down in places such as South Africa. While this appears to be an exciting breakthrough, we must remember that so far very little electricity has been provided by this form of geothermal heat, and even if successful, it will in all likelihood be decades before this technology is contributing significantly to the world grid.
Humanity is at a great crossroads. Trillions of dollars will need to be invested to make the transition to the carbon-free economy and, once a certain path of investment is embarked upon, it will gather such momentum that it will be difficult to change direction. So what might life be like if we choose one over the other? In the hydrogen and nuclear economies the production of power is likely to be centralised, which would mean the survival of the big power corporations. Pursuing wind and solar technologies, on the other hand, opens the possibility that people will generate most of their own power, transport fuel and even water (by condensing it from the air).
If we follow this second path, we will have opened a door to a world the likes of which have not been seen since the days of James Watt, when a single fuel powered transport, industrial and domestic needs alike, the big difference being that the fuel will be generated not by large corporations, but by every one of us.
This is an edited extract from THE WEATHER MAKERS: The History and Future Impact of Climate Change, by Tim Flannery. Text Publishing, $32.95
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