Nuclear Power

Larry Gilman. Environmental Science: In Context. Editor: Brenda Wilmoth Lerner & K Lee Lerner, Volume 2, Gale, 2009.


Nuclear power is energy from controlled reactions involving the nuclei (dense, tiny centers) of atoms. Nuclear power plants are large industrial facilities fueled by radioactive metals such as uranium 235 and plutonium. Uranium 235 is obtained by refining natural ores, while plutonium is an artificial element created by exposing a common but otherwise mostly useless form of uranium (uranium 238) to radiation, usually in nuclear power plants. Most nuclear power plants are fueled by uranium 235.

In a nuclear power plant, nuclear fuel is concentrated in a structure called a nuclear reactor. In the reactor, radiation from disintegrating fuel atoms is made to impinge on other fuel atoms. This triggers further disintegrations, leading to a sustained reaction that releases a flow of energy. This energy is harvested as heat, which in a typical plant is used to boil water to make steam to spin turbines that turn electric generators.

As of 2008, about 16% of the world electricity supply was produced by nuclear power plants, including 19% of U.S. supply. As most energy is consumed in forms other than electricity, especially heat and vehicular power, the nuclear contribution to world energy supply was smaller than its contribution to world electricity supply (less than 7%). There is ongoing global debate about whether building a new wave of nuclear power plants is necessary to mitigate global climate change while meeting global energy needs.

Historical Background and Scientific Foundations

The first application of nuclear fission was not to power production but was used in war—the U.S. destruction of the Japanese cities of Hiroshima and Nagasaki in August 1945 during World War II (1939-1945), which caused about 274,000 civilian deaths. Electricity from a nuclear reactor was first fed to a power grid (system of wires distributing power) in the Soviet Union in 1954.

When nuclear power first became practical, it was presented to the public as a miracle of science, promising future electricity “too cheap to meter” (in the words of the chairman of the U.S. Atomic Energy Commission, 1954). It was widely greeted by the American public on these terms. However, by the 1970s nuclear power was widely argued in the United States and Europe to entail an unacceptable threat of long-lived radioactive pollution released by disastrous accidents at nuclear power plants or waste-storage facilities. These fears were strengthened by a near-disaster at the Three Mile Island nuclear plant in Pennsylvania in 1979 and a full-fledged disaster at the Chernobyl power plant in the Ukraine (then a member state of the Soviet Union) in 1986, which spread radioactivity over much of Europe and killed thousands.

However, construction of nuclear power plants had already stalled in the United States (the world’s largest generator of nuclear electricity) before these accidents happened. As of early 2008, no new nuclear power plants had been licensed in the United States since 1978. Nuclear construction halted not because of public opposition to nuclear power but because the cost of nuclear power plants had turned out to be too high for power companies to afford.

All energy sources except the tides are ultimately nuclear in origin. The sun’s radiant energy derives from nuclear reactions in its core, and sunlight drives biological growth, winds, and precipitation. Nuclear reactions inside Earth supply the heat of geothermal energy. However, in reactors the nuclear reactions are concentrated on Earth’s surface. This creates both opportunity and danger for human-controlled nuclear reactions: The high power density of a nuclear reactor makes it possible to harvest a massive, continuous flow of energy in a nuclear power plant, but this flow is dangerous to the planet itself. Also, nuclear materials and reactions similar to those used in power generation are used to make nuclear weapons. In 2008, there was international concern over whether nuclear material had been diverted from the Iranian nuclear power program to a secret nuclear-weapons program, although the International Atomic Energy Agency of the United Nations had not found any proof of such diversion. Concern over Iran’s nuclear behavior highlights the close link between nuclear power-generating technology and bomb-building technology.

The burning of a conventional fuel such as gasoline is a chemical, not a nuclear reaction, and involves only the electrons surrounding the nucleus. A nuclear reaction changes the nucleus itself, making it into a new element or a different isotope of the same element. Thus, after fuel metal has been exposed to radiation in a nuclear reactor for some months, many of its atoms have been changed into other elements. Most of these atoms are, like the original fuel, radioactive, that is, tend to break apart spontaneously and emit fast-moving subatomic particles and high-energy electromagnetic waves (gamma rays). These particles and rays are dangerous to life because they disrupt chemical reactions in cells. At high doses, radiation kills cells directly: At low doses, it can cause cancer in multicellular organisms (such as people) by altering DNA.

As the reaction products (altered atoms) in nuclear fuel accumulate, the fuel does not work as well in the reactor. Eventually this spent fuel must be removed. Spent or used-up fuel from a reactor is a form of high-level radioactive waste, that is, material that emits intense radioactivity. Some of the radioactive substances in this waste, such as plutonium, remain dangerously radioactive for hundreds of thousands of years.

Impacts and Issues

Both supporters and opponents of nuclear power agree that high-level radioactive waste must be isolated from the environment lest it injure human beings and other creatures. They disagree, however, on whether this goal can be dependably met both for the short term (tens of years, while nuclear waste is stored inside nuclear power plants or in above-ground storage facilities) or the long term (tens to hundreds of thousands of years, the lifetime of high-level radioactive waste). Supporters of nuclear power argue that nuclear power plants will only rarely release their radioactive materials to the environment, as happened in the Chernobyl accident of 1986, and that deep burial in rock layers will isolate nuclear waste for the long term. Opponents of nuclear power argue that nuclear power plants and storage facilities can and have failed, quoting pre-Three Mile Island reassurances from pro-nuclear experts that nothing could possibly go wrong, and note that nuclear facilities may be deliberately targeted by terrorists or military enemies. They also argue that there is no way to be sufficiently confident that any waste-storage scheme, even deep burial, will be effective for hundreds of thousands of years.

Starting in the 1990s, advocates of nuclear power have turned the environmentalists’ anti-nuclear arguments on their head, urging that nuclear power, far from being an environmental threat, is the only way to generate enough electricity for modern society without worsening global warming. This argument is based on the fact that the nuclear reactions that release energy in a nuclear power plant, unlike the chemical reactions that release energy in a coal- or gas-fired power plant, do not release carbon dioxide or other greenhouse gases. An operating nuclear power plant is therefore, considered in isolation, greenhouse-neutral.

In 2005, U.S. President George W. Bush advocated massive government grants for a new round of nuclear power plants on the grounds that nuclear plants are “environmentally friendly.” In 2005, the World Nuclear Association, a nuclear industry advocacy group, recommended that between then and the end of the century, the global number of nuclear power plants be increased over tenfold, from 441 to 5,000, in order to combat global warming while meeting increased electricity demands in developing countries. The editors of the New York Times opined in 2006, “Not so many years ago, nuclear energy was a hobgoblin to environmentalists, who feared the potential for catastrophic accidents and long-term radiation contamination. But this is a new era… Suddenly nuclear power is looking better.”

Critics of nuclear power—and a very small percentage of environmentalists, despite some media claims, have switched to supporting nuclear power—respond that (1) the nuclear power cycle as a whole, including mining, refining of fuel, building plants, disposing of waste, and taking old plants apart, is in fact a significant emitter of greenhouse gases; (2) even if nuclear power were greenhouse-neutral, it is so expensive compared to other available ways of reducing greenhouse-gas emissions that money spent on nuclear power actually increases greenhouse emissions by hogging limited funds; (3) and nuclear power plants take too long to build (at least 5 years) to be part of a rapid response to climate change.

For example, prominent antinuclear energy expert Amory Lovins wrote in 2005 that the higher cost of nuclear power “per unit of CO2 displaced,” compared to efficiency, wind power, cogeneration (making electricity and useful heat together instead of discarding heat from electric plants as waste), and other renewables, “means that every dollar invested in nuclear expansion will worsen climate change by buying less solution per dollar…. In this sense of ‘opportunity cost’… nuclear power is far more carbon-intensive than a coal plant.” Lovins also argued that nuclear power plants have been rejected by market forces, so that all nuclear power plants proposed today would depend on government grants. Nuclear power advocates respond that non-nuclear alternative energy sources simply cannot produce enough energy to power modern industrial society. This debate continues. In 2005, the U.S. government allocated $6 billion in benefits for new nuclear reactors, but as of 2008, construction had not yet commenced on any new U.S. reactor.

Primary Source Connection

There are vehement arguments for and against nuclear power. The main advantage of nuclear power plants is that they do not cause atmospheric pollution. No smokestacks are needed because nothing is being burned. Nuclear power plants do not contribute to potential global warming and help countries lower their carbon footprint. For example, France initiated a large-scale nuclear program after the Arab oil embargo in 1973 and has been able to reduce its acid rain and carbon dioxide emissions by more than 40%. Shipments of fuel are also minimal and so the hazards of coal transportation and oil spills are avoided.

As with other forms of producing electricity, nuclear power generation can, however, have serious and unintended environmental impacts. The main objections to nuclear power plants are the fear of possible accidents, the unresolved problem of nuclear waste storage, and the possibility of plutonium diversion for weapons production by a terrorist group. The issue of waste storage becomes particularly emotional because leakage from a waste depository could contaminate groundwater.

Despite increased safety measures, as the following article shows, the fear of accidents remains a potent deterrent toward widespread development of nuclear power facilities.

Accidents Dim Hopes for Green Nuclear Option

The recent earthquake in Japan and accidents at two German power plants raise questions on the safety of nuclear energy as a cleaner alternative.

As concern about global warming has swelled in recent years, so has renewed interest in nuclear energy. The main reason: Nuclear plants produce no carbon dioxide or other greenhouse gases tied to climate change, at least not directly.

New reactor designs make plants safer than those operating in the days of the accidents at Chernobyl and Three Mile Island decades ago, advocates say. And there’s no group of OPEC countries in unstable parts of the world controlling the main raw material—uranium.

But that was before an earthquake in Japan this week rattled the Kashiwazaki nuclear power plant. The plant’s operator “said it had found more than 50 problems at the plant caused by Monday’s earthquake,” The New York Times reported, adding:

While most of the problems were minor, the largest included 100 drums of radioactive waste that had fallen over, causing the lids on some of the drums to open, the company said. The company said that the earthquake also caused a small fire at the plant, the world’s largest by amount of electricity produced, and the leakage of 317 gallons of water containing trace levels of radioactive materials into the nearby Sea of Japan.

Meanwhile, accidents at two German nuclear reactors last month prompted German Environment Minister Sigmar Gabriel to call for the early shutdown of all older reactors there, reports Bloomberg News.

Concern about the safety of Germany’s 17 reactors has grown after a fire at Vattenfall’s Kruemmel site June 28 and a network fault at its Brunsbuettel plant on the same day. Der Spiegel online adds:

It took the fire department hours to extinguish the blaze. Even worse, the plant operator’s claim that a fire in the transformer had no effect on the reactor itself proved to be a lie.

In short, the incident made clear that nuclear energy is by no means the modern, well-organized, high-tech sector portrayed until recently by politicians and industry advocates. Indeed, the frequency of problems occurring at Germany’s aging reactors is on the rise. Just as old cars succumb to rust, nuclear power plants built in the 1970s and ‘80s are undergoing a natural aging process.

On Wednesday, the chief executive of Vattenfall Europe AG stepped down. Klaus Rauscher was the second manager to depart this week amid mounting criticism for the utility’s handling of a fire at a nuclear plant in northern Germany, reports the AP.

‘When it comes to security at nuclear power plants, I can only say, that when it comes to the information policy, this really has not been acceptable and therefore my sympathy for the industry is limited,’ Chancellor Angela Merkel said.

Merkel, a physicist by training, normally favors nuclear power, but the June 28 fire at the Kruemmel plant, near Hamburg, has put the industry in a bad light.

Still, nuclear power has won some powerful allies in the environmental community, writes E Magazine editor Jim Motavalli on the web site AlterNet.

He quotes Fred Krupp, president of Environmental Defense, as saying, “We should all keep an open mind about nuclear power.” Jared Diamond, best-selling author of “Collapse,” adds, “To deal with our energy problems we need everything available to us, including nuclear power,” which, he says, should be “done carefully, like they do in France, where there have been no accidents.”

Stewart Brand, who founded The Whole Earth Catalog and Whole Earth Review, concludes, “The only technology ready to fill the gap and stop the carbon dioxide loading of the atmosphere is nuclear power.”

Environmentalists continue to push for more benign sources—wind, biomass, geothermal, and solar, as well as greater conservation—to power the world.

But The Washington Post reports that “Most of the technologies that could reduce greenhouse gases are not only expensive but would need to be embraced on a global scale.” The article continues:

Many projections for 2030 include as many as 1 million wind turbines worldwide; enough solar panels to cover half of New Jersey, massive reforestation; a major retooling of the global auto industry; as many as 400 power plants fitted with pricey equipment to capture carbon dioxide and store it underground; and, most controversial, perhaps 350 new nuclear plants around the world.

That kind of nuclear expansion in the US seems unlikely. The country hasn’t licensed a new plant in more than 30 years, and the devilish political and scientific subject of radioactive waste disposal has yet to be fully addressed.

But that hasn’t stopped other countries from pushing ahead. Russia “hopes to export as many as 60 nuclear power plants in the next two decades,” The Christian Science Monitor reported this week, including what would be “the first-ever floating atomic power station” at sea.

But noting an estimate from the Massachusetts Institute of Technology, The Salt Lake Tribune in Utah reports that “at least 1,000 new nuclear plants would be needed worldwide in the next 50 years to make a dent in global warming.”

[Kickerbocker, Brad. “Accidents Dim Hopes for Green Nuclear Option.” Christian Science Monitor, July 19, 2007.]