There are currently 103 nuclear power plants in the US. These plants produce 20 percent of our electricity and over 70 percent of our emission-free electricity from all sources. Over 400 nuclear power plants in 25 countries worldwide produce 17 percent of the world’s electricity. These facilities reduce CO2 emissions by over 2 billion metric tons per year. Nuclear energy supplies electricity each year to serve 60 million homes. There are currently 103 nuclear power plants in operation in the United States, yet, how many of us understand how these plants produce the energy that we use?
The fission of an atom of uranium produces ten million times the energy produced by the combustion of an atom of carbon from coal. There is more energy in the uranium impurity in coal than the amount we derive from the burning of coal. Solid waste from coal burning, which includes the permanently toxic metals mercury, arsenic and selenium, is produced a thousand times faster than waste from nuclear power plants.Coal plants put more radiation into the atmosphere than nuclear power plants through the combustion of impurities in the coal.
Nuclear Fuel Cycle
Nuclear energy can be generated from the fission of uranium, plutonium or thorium. Nuclear power plants currently use enriched U-235. Uranium ore is extracted from mines then sent to a processing plant for enrichment. This enriched fuel is then transported to the nuclear power plant to be converted to electrical energy.
A reactor core contains a number of rods. Each rod is full of uranium oxide pellets. When these pellets are bombarded with neutrons, the atoms split and release heat and neutrons in a chain reaction. This produces steam, which powers a turbine and produces electricity.One uranium fuel pellet is roughly equal to 17,000 cubic feet of natural gas, 1,780 pounds of coal, or 149 gallons of oil.
Nuclear waste consists of fission products. They are highly radioactive at first, but the most radioactive isotopes decay the fastest. Spent rods are placed in “cooling ponds” inside the reactor.
About one cubic meter of waste is generated by a power plant each year. After 10 years, the fission products are 1,000 times less radioactive, and after 500 years, the fission products will be less radioactive than the uranium ore from which they originally came.
Besides fission products, spent fuel rods contain some plutonium which is produced when the U-238 in the reactor absorbs a neutron. This plutonium and leftover uranium can be separated in a reprocessing plant and reused as reactor fuel. Reprocessing has not been done in the US since the Carter administration, but it is done by other countries.
It is believed that with fourth generation breeder reactors which reuse fission products such as U-238 and plutonium, we may have ample energy for billions of years. Current reactors only use uranium-235. This is less than 1% of naturally-occurring uranium. New generation reactors with onsite fuel reprocessing can use nearly 100% of the uranium. And, enough U-238 has already been mined so that breeder reactors could provide U.S. electricity needs for over 500 years with current supplies alone, eliminating the need for costly and destructive uranium mining.
By reusing fission products, breeder reactors would cause the shut down of the uranium mining industry for decades while simultaneously eliminating built-up nuclear waste from the past 30 years and weapons from the arms race. Uranium enrichment facilities could also be shut down.
Advantages of Nuclear Power
Radioisotopes decay exponentially, meaning that as time goes on, nuclear waste becomes less dangerous . The longest lived fission product has a half life of about 30 years. Compare this to the mercury and arsenic wastes from coal burning, which will be just as hazardous in ten thousand years as they are today.
A decade worth of high level waste from all US reactors could fit into a single Boeing 777 freighter. All of the high level waste produced in the United States in the last 30 years could fit onto a single football field.
Since 1973, nuclear energy has displaced 4.3 billion barrels of imported oil and reduced our trade deficit by $12 billion. Nuclear energy cuts our dependence on foreign imported oil.
Nuclear power plants do not pollute the air with nitrogen oxides, sulfur oxides, dust or greenhouse gases like carbon dioxide. In other words, they emit no greenhouse gases.
Nuclear plants reduce greenhouse gas emissions by 20 percent (about 128 trillion tons per year). Without nuclear power plants, nitrogen oxides emissions would be 2 million tons higher per year and sulfur dioxide emissions would be 5 million tons higher per year.
In the 1980s, France tripled its nuclear energy production, reducing pollution from their electric power system by 80-90 percent. France currently derives 80% of its energy from nuclear power plants. No power plant accidents have occurred there in over 40 years of operations.
U.S. nuclear power plants generate about $20 million in state and local tax revenues.
You would have to live near a nuclear power plant for over 2,000 years to get the same amount of radiation exposure that you get from a single diagnostic medical x-ray.
Nuclear power is not subject to the same price fluctuations as fossil fuels, which depend on a constant stream of fuel. Nuclear power does not depend on the weather and is immune to the political turmoil of fossil fuel providers. It provides us with a self-sufficient, dependable, 24×7 source of energy.
Compared to other large scale sources of energy, nuclear power is by far the safest. It is heavily regulated and stringent safety measures in both the design and use of power plants are in place.
Generation III+ reactors are relatively quick to build, use less material, are cheaper and more reliable to operate than in years past and they produce less radioactive waste.
After about three years in the reactor core, rods lose their ability to produce heat effectively. These spent rods remain radioactive and if not reprocessed (which is currently not done in the U.S.) they require storage away from humans for 500-10,000 years. Power plants must shut down to remove and replace spent rods.
Uranium processing produces radioactive wastes that must be adequately stored and isolated. Uranium mining can destroy or degrade a mined area, leading to numerous effects on the environment. In-situ uranium mining consumes enormous amounts of water and is usually done in areas that are already water-poor.
Transporting nuclear waste is dangerous. A crash or attack could cause radioactive waste to leak. Building the proposed nuclear waste facilities at Yucca Mountain, Nevada, and Skull Valley, Utah, would cause radioactive shipments to travel through 44 states and the District of Columbia.
The Department of Transportation allows spent nuclear fuel to be shipped in mixed-freight rail cars alongside cars carrying flammable or explosive materials. In the event of an incident with flammable or explosive materials, the nuclear transport would be affected.This could have devastating impacts on the land, people and animals near such an explosion.
In the past decade, waste disposal companies have contacted more than 50 U.S. indigenous groups, offering millions of dollars in exchange for the right to dump U.S. wastes on Native lands. Reservations are not subject to state, county, municipal and many federal waste-facility operating standards so dumping on Native lands becomes a “cost-effective” measure for such companies, but at what expense to the Natives and others living in and around these areas?
Integrated Fast Reactors as a possible solution
The Integrated Fast Reactor (IFR) is a fourth generation breeder reactor that can be fueled entirely with material recovered from today’s used fission products from older reactors and weapons left over from the arms race. IFR consumes virtually all long-lived radioactive isotopes. It uses uranium with 100 to 300 times the efficiency of today’s reactors, including the U-238 that comprises about 95% of uranium but which cannot be used by older style reactors.
Breeder reactors get 100-300 times the energy from a kilogram of uranium than do current reactors. All the enriched uranium used in nuclear reactors and all the U-235 used in nuclear weapons has been separated from U-238, and the leftover U-238 is still available. If this U-238 were used to generate energy in breeder reactors and the electricity were sold at present prices, the present American stock of depleted uranium would generate $20 trillion worth of electricity.
Current reactors require enriched uranium; IFR does not. Adopting breeder reactors would essentially shut down the uranium mining, enrichment and disposal industries which are the cause of much concern.
Because reprocessing of spent fuels is done onsite, there is very low proliferation potential. No fissionable products become externally available.
IFRs produce 24×7 power and can be built anywhere there is water. The power is inexpensive (some estimates are as low as 2 cents/kWh to produce). As with all nuclear power plants, the IFR emits no greenhouse gases and effectively displaces other electrical utilities whose waste is damaging our biosphere.
The IFR gains safety advantages through a combination of metal fuel (an alloy of uranium, plutonium, and zirconium), and sodium cooling. This set-up conducts heat from the fuel to the coolant at relatively low temperatures. The IFR takes advantage of expansion of the coolant, fuel, and structure in case of a “melt down” incident. The expansion of the fuel and structure means that in the event that overheating begins in the core, the physics of the reactor cause it to naturally shut down without human intervention.
The IFR was a project that ran from 1984-1994 at Argonne National Laboratory near Chicago. In 1994, funding for the project was cut and the project was shelved.
Industrial society depends on inexpensive and abundant energy.Since 1960, nuclear power has been the world’s fastest growing major source of energy. Today, nuclear power provides one-sixth of global electricity to two-thirds of humanity in 44 countries. New generation nuclear power stations and breeder reactors close the nuclear fuel cycle by re-using fission products, thereby eliminating issues with nuclear waste and uranium mining. Yet the question still remains as to whether the benefits of developing nuclear power outweighs the risks.
