Nuclear Power Plants as Electricity Generators

Solution or illusion?

© 2007 Dr Ron Nielsen

Democracy is much too important to be left to public opinion.
Walter Lippmann (1889 - 1974) US journalist, editor, and author.

At the bottom of all the tributes paid to democracy is the little man walking into the little booth with a little pencil, making a little cross on a little bit of paper.
Winston Churchill

There is no easy solution to our increasing energy demands and nuclear technology could be considered as one possible way to meet these demands. However, we have many other alternative and safer options, and the question is whether the use of nuclear technology is really necessary. In particular, is it really true, as claimed by the Australian government, that anyone who takes climate change seriously should embrace the idea of nuclear energy. This article is about the proposed nuclear technology in Australia but we shall also look at the future of nuclear energy in the world.

A release of a Draft Report entitled "Uranium Mining, Processing and Nuclear Energy Review" has been announced on 21 November 2006 at a meeting of  the National Press Club in Australia. The date of the publication, as it appears on the Report, is December 2006. The closing date for submissions of any comments was 12 December 2006.

So if you blinked and missed it, it is your fault. You have been given a chance and if you have not done anything it means that you either agree or do not care. You cannot complain that your democratic rights have been violated or ignored.

Q. Why is nuclear energy so attractive?

A. One of the reasons nuclear energy is so attractive is because nuclear fission reactions do not produce carbon dioxide. However, carbon dioxide is produced during mining, extracting yellow cake from the ore, refining it, transportation, and eventually in decommissioning of nuclear power plants. These contributions are small when compared with carbon dioxide emissions from fossil fuel power plants.

Another reason why nuclear technology is so attractive is that during fission reactions small amounts of mass are released as huge amounts of energy, according to the well-known mass-energy relation E = mc2. As an example we can use 1 kg of mass and calculate how much energy we could have if we could convert it to energy. The speed of light in vacuum is c = 3 x 108m/s. Therefore

E = 1kg x (3 x 108m/s)2 = 9 x 1016J = 25TWh

Thus, if we could convert 1kg of mass into energy and if we could use 100% of this energy to produce electricity we could generate 25 trillion watt-hours of electricity. For instance, considering the current consumption of electricity in Australia, just 500g of matter converted directly to electricity could be used by one million people for one year. Of course, during the conversion of nuclear energy to electricity, much of the generated energy is lost. Nevertheless, the mount of nuclear fuel before and after nuclear fission reactions is approximately the same.

Q. The Australian proposal is to install 25 nuclear power plants as electricity generators in Australia by 2050. Will it be enough? How much electricity will they produce?

A. To answer these questions we have to consider how much electricity we are going to consume in 2050 and what kind of nuclear power plants we are going to have.

Let us look first at the consumption of electricity in Australia because the proposal is to build nuclear power plants in this country. Later, we shall consider the consumption of electricity in the world.

Annual consumption of electricity in Australia.
Annual consumption of electricity in Australia.
By 2050, the annual consumption of electricity in Australia will double compared to the consumption in 2000.

Examples of nuclear power plants as electricity generators
Examples of nuclear power plants as electricity generators.
Example: A nuclear power plant in the UK produces on average 3.6 TWh of electricity per year.
OECD means the average in OECD countries.

Nuclear power plants, as electricity generators, proposed and required
The number of proposed and required nuclear power plants working as electricity generators in Australia in 2050
Example. The purposed number of nuclear electricity generators is 25 but the required number is 53 if they are going to be of the type operating in the US.

The Report claims that the proposed nuclear power plants working as electricity generators will produce at least 1/3 of the required electricity in 2050. If this is true then they will be more powerful than in the UK but less powerful than an average power plant in OECD countries.


Q. Is the target year of 2050 realistic from the point of view of climate change? Will it not be too late? What are the expected changes in global climate by 2050?

Carbon dioxide concentration
Carbon dioxide concentration
The pre-industrial carbon dioxide concentration in the atmosphere was 280 parts per million per volume (ppmv). With business as usual (BAU), the concentration in 2050 will nearly double. However, if we work hard and reduce substantially our emissions of carbon dioxide, we might be able to finish with a lower concentration indicated here by 2050 low.

Global temperature increase
Global temperature increase
The average global increase in the surface temperature in the past century was 0.60C. The projected increase by 2050 is an additional 0.80C if we are lucky, which will be about 30% higher than the increase in the last century. More likely, the additional increase will be 2.60C, that is, about 4 times higher than the increase in the past century.

The increased surface temperature increases the rate of evaporation and causes more intense precipitations. The land will be drier, weather conditions will be more violent, floods, storms, and cyclones more devastating, water availability will be lower, the number of days with excessively high temperatures in summer will be higher, the number of death caused by heat waves will increase.

Economic losses will increase. The number of natural disasters in Australia with economic losses greater than $10 million (AUD) increased from about 4 per year in 1967 to about 14 in 2000. (This is not a prediction but a recorded trend.) Examination of the trend indicates that they are increasing faster than proportionally in time. However, even if we take an optimistic assumption that they are increasing linearly, the number of such large-scale disasters in Australia will increase to about 28 per year in 2050.

In terms of 2001 US dollars, global weather related economic losses in the past century increased from $89 billion per decade in 1980-1989 to $474 billion per decade in 1990-1999. A tentative projection indicates that by 2050 they might be as high as our global income.

The authors of the Draft Report (one of them is my colleague) are no doubt sufficiently informed about nuclear energy but they appear to be less acquainted with the environmental threats and trends. By 2050 it will be too late to do anything about climate change with our puny 25 nuclear power plants.

Q. How much less of carbon dioxide we can expect to emit if we have the proposed 25 nuclear power plants by 2050?

A. The Report expects that we might be able to reduce our carbon dioxide emissions by about 8-18% in 2050. However, we should remember that carbon dioxide emissions per person in Australia are already excessively high. Carbon emissions are also continually increasing, so by 2050 the 8-18% reduction will be on top of a considerably large increase, and thus will have no influence on reducing our contribution to global warming.

There is an uncertainly about our place in the world with carbon emission. This is probably because our emissions per person are not only high but also continuously increasing. However, currently we are either on the second or the first place among the industrial nations.

According to the the World Bank online data base 2004, emissions in Australia were close to 18 tonnes of CO2 per person per year, compared to around 20 tonnes per person in the US and 12 tonnes per person the average emissions in high-income countries. So if we wanted to bring our emissions to the average level of most high-income countries we would have to reduce our emissions now by about 30%, and even by much more in 2050. The expected 8-18% reduction in 2050 sounds ridiculously low.

According to the CDIAC (Carbon Dioxide Information Analysis Center) carbon dioxide emissions per person in the US have been nearly constant (at around 20 tonnes of CO2 per person per year) in the last years, but in Australia they were steadily increasing from about 7 tonnes of CO2 per person per year in 1950 to around 18 in 2000. The trend is strong and steady and it shows no sign of leveling off, so by 2050 our CO2 emissions per person could be frightfully high. We are on the way to be the world leaders in this ignominious activity.

Fortunately, our combined contribution to climate change is relatively small because the population in Australia is small. The expected 8-18% reduction in 2050 will have no effect on climate change. It will be too little too late.

Q. What is the estimated capital cost of building the proposed 25 reactors?

The approximate capital cost of a nuclear power station is $2 billion (AUD) per one  billion watts (one GW), which is about US$1.5 billion. It costs a little less per GW to build a large power plant. For practical reasons, it is better to calculate the capital costs per amount of electricity a power plant is expected to deliver to users. The capital cost of an average nuclear power power plant in the US is about US180 million per TWh but in the UK it is US$220 million per TWh. On average we have a good round figure of US$200 million per TWh.

Considering that we shall need 412 TWh electricity per year in 2050 and assuming that, as the Report claims, the 25 proposed rectors will produce 1/3 of this electricity, the capital cost will be (412/3)x200 = US$27 billion, which is about AU$37 billion.

Q. What is the expected cost of electricity produced by nuclear power stations?

A. The Report estimates an increase by 20-50%. This will presumably include not only the capital cost spread over a lifetime of a nuclear power plant, which is about 40 years, but also the cost of the disposal of radioactive waste, decommissioning, and all other ongoing costs.

Q. The Report claims that "If, as it happens in some parts of the world, power plants using fossil fuels are required to pay for their emissions, this cost difference disappears." How will it work?

A. Yes, precisely, I also wonder how it is supposed to work. This is a complete nonsense. If conventional power plants are going to pay for their emissions then the increased costs of producing electricity will be passed to users. You will be paying 20-50% more for the electricity generated by nuclear power plant and you will be paying more for the electricity generated by fossil-fuel power plants because these plants will be required to pay for their emissions. The money they are going to pay will not be diverted to you but will flow through them from your pocket to government coffers.

Q. Is nuclear technology an answer to our increasing energy demands? How much uranium do we have in the world and how long will it help us to produce the required energy?

The Report claims that "With the present levels of use and current technologies, existing economic reserves of uranium are sufficient to produce nuclear fuel for 50-100 years."

This estimate, while being correct, is disappointingly low. It agrees with the often-quoted figure of 75 years. We now have only about 440 nuclear power reactors and the combined energy they produce accounts for only about 6% of global energy consumption and for about 17% of the global consumption of electricity. So why to make so much fuss about nuclear energy if we can do much better with alternative sources of energy?

For instance, looking globally, if we assume the lowest possible potential for solar systems (see my estimates), the lowest conversion efficiency, and only 1% of unusable land area, we can calculate that we could produce about 3 times more electricity than we globally consume. The Sun delivers so much energy to the Earth that with improved technology solar systems could generate enough energy for significantly longer time.

It is true that clean alternative sources of energy are currently more expensive, but it is also true that in our calculations we are neglecting the costs of environmental damage. Someone will have to pay for fixing it and the price will be high. Indeed, the price might be prohibitively high. It is possible that some of the damage will never be fixed. So either we play it safe and pay more now, or behave dangerously and irresponsibly and pass the burden of the environmental damage to our children. However, with the way we now ruthlessly exploit our planet's resources it is not at all certain whether our children will have a place to live.

Q. It’s a highly hypothetical question but what would be the scale of the operation if we wanted to replace the existing electricity generating technology by nuclear power plants? How many reactors would we have to have in the world? How much would it cost to build them?

A. As mentioned earlier nuclear power reactors contribute little to our global energy production and they are not expected to have substantially higher contribution in the future. They will remain as a marginal source of energy for a long time. Thus for instance, by 2020 their projected contribution to global energy production will be only 5%. Yes, that is right, it will decrease.

Their contribution to global production of electricity in 2000 was 18.3%. Now it is about 16.8%, by 2020 it will be 11.9% and by 2050 only 8.4%. In contrast, the projected production of electricity by plants based on fossil fuels is not around 63% and will be 74.3% in 2050.

In order to appreciate the scale of the operation, (if we wanted to replace the current electricity generating plants based on fossil fuels by nuclear power plants) we have to look first at the global electricity production and its component, which comes from plants based on fossil fuels.

Global electricity generation
Global production of electricity
Global production of electricity in 2000 was 13225 TWh per year. The contribution from fossil-fuel power plants was 8028 TWh per year. The projected total production in 2050 is 36019 TWh/y, that is nearly three times as high. The expected contribution from fossil-fuel power plants is 26762 TWh/y.

Existing nuclear reactors
The total number of the existing (2006) nuclear power plants working as electricity generators
The existing (2006) nuclear power electricity generators are located mainly in OECD countries (351). Only 92 are in the rest of the world.

Existing and required nuclear power plants as electricity generators
The number of existing and required nuclear power plants working as electricity generators
This graph answers the following question: How many nuclear power plants would we have to build in the world if we wanted to replace the fossil-fuels power plants?


The number of existing nuclear power reactors (in 2006) in the world is 443. Using their average annual output of electricity we can calculate that to replace the currently operating plants based on fossil fuels we would have to have 1587 nuclear power reactors or about 3.6 times more than we have now. In 2050 we would have to have 4316 nuclear power plants, or about 10 times more than we have now.

If the estimates of the authors of the Draft Report are correct, with 1587 reactors in place now we would have used all known uranium deposits in 14-40 years. Using other estimates of economically viable uranium deposits the number is around 22 years. The fun would be over and we would be left with millions of tonnes of highly radioactive waste in the form of spent fuel, not to mention depleted uranium and uranium tailings.

As for the capital cost involved in the construction of so many nuclear power plants we can easily calculate that to replace all the existing fossil-fuel power plants we would have to invest about US$6 trillion, which is about 1% of our global income. To replace them all in 2050, the capital cost would be around US$14.4 trillion.

Q. Is nuclear energy a solution to global warming? Suppose we could quickly replace the existing power plants by nuclear facilities. How much would this help in reducing our impact on the ongoing global warming?

A. To answer this question we have to look at the anthropogenic sources of carbon dioxide.

Global carbon dioxide emissions by sector
Global carbon dioxide emissions by sector
(Based on the data of the IEA World Energy Outlook 2004.)

Only about 40% of global emissions of carbon dioxide come from the production of electricity. The remaining 60% is from other sources. So, even if we replaced all the existing and future fossil-based power stations by nuclear power reactors we would be still emitting carbon dioxide. The reduction would certainly help, if we could do it, but it would not solve the problem of global warming. Maybe it would soften the blow a little. However, as mentioned earlier, we simply cannot do it first because we cannot build so many nuclear power plants in a hurry all over the world (see window of opportunity), and second because we do not have enough uranium to power the required ever increasing number of nuclear power plants. Nuclear power plants cannot be used to soften our impact on global warming and on the resulting climate change.

We should also remember that the lifetime of carbon dioxide in the atmosphere is over 100 years. What it means is that after about 100 years or more, its concentrations will be reduced to 37% of the concentration at the starting point. If we stopped all the emission from tomorrow, we would still have to live with the effects of the atmospheric pollution for 100 years or more. The climate would continue to change but only hopefully with less dramatic results.

Q. Australia will almost certainly increase uranium production and export. Will it increase the danger of the proliferation of nuclear weapons and terrorism?

A. The claim is that our exports will be strictly controlled and regulated so in theory they should be safe. However, in practice, the more we dig and distribute around the world the higher is the risk that some undesirable leaks will develop and certain amounts of uranium will be directed or diverted to hostile recipients.

According to ElBaradei, director of the International Atomic Agency Authority (IAEA), "nuclear weapons capability could spread to as many as 30 more countries in the coming decades if the trade in nuclear fuel continues on its present course." (Science, Vol. 315, 9 February 2007, p. 791.)

Q. So what is a possible solution to our increasing energy demands?

A. There is no single simple solution. In the future, or indeed starting from now, we should not think in terms of one major source of energy such as fossil fuels in the past, but in terms of diverse sources, each contributing a little to our energy production. One thing is certain: if we want to survive we should phase out the use of fossil fuels as quickly as possible. However, from what we know, this will not happen, which means that our future is at best uncertain.

We have a huge potential in a variety of clean alternative sources of energy (solar systems, windmill electricity, hydroelectricity, geothermal and tidal energy) discussed extensively in The Little Green Handbook and we should be working harder on their implementation. We should also work harder on developing alternative but safer sources or nuclear energy, such as thorium-based reactors and the illusive but clean nuclear fusion energy.

Of the two evils, fossil-based power plants and nuclear power reactors, nuclear appears to be less harmful. However, considering the time frame, nuclear power plants are definitely not a good option. Our window of opportunity is expected to close around 2020. Within this short time it will be impossible to have more than about one nuclear reactor working in Australia. We have far better options, which I am going to discuss in a separate article.

Thus, in conclusion, the proposed nuclear power plants in Australia have nothing to do with our attempt to fight global warming. It is a misguided proposal that will neither help to reduce our impact on global warming nor solve our energy problems. It will be all too little too late.

 

Source: Much of the information presented here is based on the data in The Little Green Handbook.

Copyright: You are welcome to use the presented here material but please make a reference to: Nielsen, R. 2006, Nuclear Power Plants, http://home.iprimus.com.au/nielsens/