Sunday, August 19, 2007

Is nuclear energy a solution to global warming?

The MIT study

In 2003 an interdisciplinary study group at Massachusetts Institute of Technology published a study called The Future of Nuclear Power. The study is worth reading in full, but what I would like to focus upon here is a few of their observations and one of their important underlying assumptions.

First, the conclusion that the study reaches is that global warming due to greenhouse gas emissions as a result of human energy consumption is a serious problem that must be addressed. In that context, the study says that are there are possible strategies for reducing greenhouse gas emissions, and that at this time none of those strategies should be rejected. The four strategies are:

  1. increasing efficiency in electricity generation and use;
  2. expanding the use of renewable energy sources such as wind, solar, biomass and geothermal;
  3. the sequestration of carbon, that is, capturing carbon dioxide emissions at coal-fueled electrical generating stations and isolating it in places where it cannot easily enter the atmosphere; and
  4. increasing the use of nuclear power.

Of those four strategies, all of which the study advocates using, the only one it studies in some depth is the use of nuclear power. It's recommendation is that at this time the best strategy would be to have 1000-1500 nuclear reactors around the world in use by the year 2050.. As of 2003, says the report, there were 366 nuclear reactors in service. So the recommendation is that during the next 43 years the number of nuclear reactors in the world be a little more than doubled at least and a little more than quadrupled at most. This would require the building of somewhere between fifteen and twenty-six nuclear reactors every year between now and 2050.

Hazards of increased use of nuclear power

The MIT study outlines several hazards of the increased use of nuclear-generated electricity. The principal concerns as with safety of using nuclear power, security risks of producing and storing nuclear fuel, and unresolved problems of waste disposal.

Safety

No nuclear plant design, says the study, is totally risk free. The possibility of leaks of hazardous levels radioactive materials into the environment arises from two realities: 1) any complex technological system is prone to having flaws in the design, and 2) any technological system operated by human beings is prone to human error. The most one could hope for, says the study, is to keep the probability of accidents down to an acceptable level. The acceptable level they suggest is one serious accident per fifty years. This level represents a ten-fold reduction in serious accidents from the level that has been attained up to this time.

It is worth asking how likely it is that a ten-fold reduction in the rate of accidents could be achieved. Even maintaining current levels of safety would require a steady repair of already existing nuclear plants, many of which in the United States are already older than the forty years for which they were designed to operate. Of at least equal concern is that maintaining and operating nuclear power facilities would require constantly educating people to serve as operators. In an atmosphere of general decline in education in the United States in mathematics and the sciences and technology, there is no reason to be optimistic that reliable operators will continue to be trained in the United States. In many important ways, the culture of expertise in the United States is in decline, and there are at present no signs that this trend will soon be reversed.

Waste management

Under this heading the report says:

The management and disposal of high-level radioactive spent fuel from the nuclear fuel cycle is one of the most intractable problems facing the nuclear power industry throughout the world. No country has yet successfully implemented a system for disposing of this waste.

At present there is only one site for high-level waste management in the United States, namely, Yucca Mountain in Nevada. To accommodate the proposed increased use of nuclear power, says the study, there would have to be similar storage facilities created somewhere in the world every three to four years. Moreover, the problem of safely moving radioactive waste from nuclear plants to these facilities would have to be solved much better than is now the case. While the short-term risks ofradioactive contamination are not too serious, says the study, the long-term risks are much more serious. Again, maintaining disposal sites requires the very best in technology and in human training and moral integrity. In a rapidly changing world such as ours, neither of these requirements can be counted on.

Security risks

Another hazard that has yet to be resolved satisfactorily is the likelihood of enriched uranium and plutonium falling into the possession of people who would not use it for peaceful purposes. It appears that the current trajectory of human civilization is not in the direction of greater co-operation and harmony. Even if hostilities around the world did not rise from their current levels, the likelihood of discontented groups of individuals breaching nuclear facilities or fuel-generating plants with catastrophic consequences for thousands or millions of people is a sobering reality.

Availability of fuel

One further point the study makes, albeit as a positive point, is that one can expect the world's supply of easily available uranium to last for approximately fifty years. After that, resources will be most probably become scarce. What the study does not say spell out is that when uranium becomes scarce, then a world that has become dependent on it for electrical production will be as likely to fight over scarce nuclear fuel as it has been to fight over dwindling fossil fuel resources. In other words, the nuclear solution is another short-term solution. Unlike others, however, it is accompanied by serious potential risks of catastrophic consequences, especially in the long term.

Unexamined presupposition

Despite all these potential risks, the MIT study group concludes that increased use of electricity produced by nuclear processes is less likely to produce disastrous consequences than the continued use of fossil fuels at current levels. That conclusion is very sobering for two reasons: it highlights just how serious the consequences of continued use of fossil fuels are, and it makes it sound as though there is no alternative to living in a world that is increasingly compromised by human consumption of energy.

What the study assumes is that human beings will continue to use electrical energy at the same rate of acceleration as it has during the past fifty years. Energy consumption in the United States has quadrupled during the past fifty years, as the population of the country has doubled. That means per-capita energy consumption in the United States has doubled. No responsible scientist of policy maker believes our current level of energy consumption is sustainable. It simply cannot continue to increase. Itcannot even remain at anything near its present rate.

Conclusion

Unlike the MIT study group, I am inclined to say that increased use of nuclear-energy-fueled electricity production is not a strategy that it would be responsible to pursue in the United States or anywhere else in the world. We who are living now owe it to future generations to find a way of living that dramatically reduces our negative impact on the environment. The increased use of solar, wind and geothermal energy is something to pursue. But even more important is a significant reduction of our use of electricity and other alternatives to using the energy of our own muscles. The human being is not designed to do as little physical work as most people in “developed” countries now do. When a human body does too little walking, lifting, carrying, reaching and moving, it tends to become overweight and to suffer a wide range of threats to health.

The next time you go to the gym to use electricity-driven machines to do some kind of exercise that could much better be done by using your body to do work and by using the legs to get from one place to another, ask yourself: What is wrong with this picture?

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