RealClearScience
May 19, 2011
By Joseph Archer
Today’s nuclear power plants are unsafe and expensive. However, it doesn’t have to be that way. A cleverly designed plant could be both safe and cheap. Thankfully, such a design already exists. It’s called the Thorium Fluoride Reactor (TFR).
The most common nuclear power plant design, the Light Water Reactor (LWR), is nothing but a scaled up model of a reactor initially meant to power submarines. Unfortunately, this causes enormous problems, such as the need to enrich fuel, build gargantuan pressure vessels, and deal with long-lived nuclear waste. It is also tremendously expensive. In short, it was never meant to be a civilian source of electricity.
Now, following the release of radioactive material at the Fukushima plant in Japan, activists around the world threaten to eliminate nuclear power as an acceptable energy source. However, before governments indulge that knee-jerk response, they should consider the tremendous benefits of TFR.
The fuel is in the form of a fluoride salt with a melting temperature of approximately 600 degrees Fahrenheit. Because the system is not pressurized, any reactor breach leading to a release of fuel would be driven only by gravity. Thus, the fluoride salt, instead of being blown into the atmosphere, would cool and solidify. Hazardous radioactive material would be frozen into place in the shape of easily cleanable salt crystals.
To further guard against a catastrophic release of radioactive material, the TFR is designed to have fuel added and radioactive fission products (nuclear waste) removed on a continual basis. The fission products, therefore, do not concentrate within the fuel. This prevents the reactor from containing an excess of fuel reactivity at any given time. The most problematic waste products are gases, such as iodine and xenon, but the continual elimination of these gases and other radioactive fission products effectively eliminates the potential for catastrophe.
Additionally, far less radioactive material is needed to operate a TFR plant. Whereas conventional uranium plants create 35 gigawatt-hours of electricity per metric ton of uranium, TFR creates 11,000 gigawatt-hours of electricity per metric ton of thorium. The waste generated by TFR must be stored for only 300 years, as opposed to the thousands of years required for the waste generated by uranium plants.
In regard to expense, the TFR itself consists of little more than a low-pressure fluid circuit filled with a low-cost, molten fluoride salt. There is neither a massive high-pressure system nor thousands of fuel rods. There is also no need for a fallible decay heat removal system. Because the core essentially has no complex internal components, the power output of the reactor is limited only by how rapidly molten salt can be forced through the core. A single TFR, with the same size core as a conventional reactor, could produce literally tens of times as much energy. These two factors, simplicity of construction and an increased energy output, even suggest that TFR would be cheaper than coal-powered electricity.
If the goal of nuclear energy is to construct a failsafe, inexpensive facility, then energy policy analysts need look no further: The Thorium Fluoride Reactor is ready for business.
Joseph Archer is a professional engineer with a degree in nuclear engineering.
http://www.realclearscience.com/articles/2011/05/19/safe_cheap_nuclear_thorium_fluoride_reactors_106239.html
May 19, 2011
By Joseph Archer
Today’s nuclear power plants are unsafe and expensive. However, it doesn’t have to be that way. A cleverly designed plant could be both safe and cheap. Thankfully, such a design already exists. It’s called the Thorium Fluoride Reactor (TFR).
The most common nuclear power plant design, the Light Water Reactor (LWR), is nothing but a scaled up model of a reactor initially meant to power submarines. Unfortunately, this causes enormous problems, such as the need to enrich fuel, build gargantuan pressure vessels, and deal with long-lived nuclear waste. It is also tremendously expensive. In short, it was never meant to be a civilian source of electricity.
Now, following the release of radioactive material at the Fukushima plant in Japan, activists around the world threaten to eliminate nuclear power as an acceptable energy source. However, before governments indulge that knee-jerk response, they should consider the tremendous benefits of TFR.
The fuel is in the form of a fluoride salt with a melting temperature of approximately 600 degrees Fahrenheit. Because the system is not pressurized, any reactor breach leading to a release of fuel would be driven only by gravity. Thus, the fluoride salt, instead of being blown into the atmosphere, would cool and solidify. Hazardous radioactive material would be frozen into place in the shape of easily cleanable salt crystals.
To further guard against a catastrophic release of radioactive material, the TFR is designed to have fuel added and radioactive fission products (nuclear waste) removed on a continual basis. The fission products, therefore, do not concentrate within the fuel. This prevents the reactor from containing an excess of fuel reactivity at any given time. The most problematic waste products are gases, such as iodine and xenon, but the continual elimination of these gases and other radioactive fission products effectively eliminates the potential for catastrophe.
Additionally, far less radioactive material is needed to operate a TFR plant. Whereas conventional uranium plants create 35 gigawatt-hours of electricity per metric ton of uranium, TFR creates 11,000 gigawatt-hours of electricity per metric ton of thorium. The waste generated by TFR must be stored for only 300 years, as opposed to the thousands of years required for the waste generated by uranium plants.
In regard to expense, the TFR itself consists of little more than a low-pressure fluid circuit filled with a low-cost, molten fluoride salt. There is neither a massive high-pressure system nor thousands of fuel rods. There is also no need for a fallible decay heat removal system. Because the core essentially has no complex internal components, the power output of the reactor is limited only by how rapidly molten salt can be forced through the core. A single TFR, with the same size core as a conventional reactor, could produce literally tens of times as much energy. These two factors, simplicity of construction and an increased energy output, even suggest that TFR would be cheaper than coal-powered electricity.
If the goal of nuclear energy is to construct a failsafe, inexpensive facility, then energy policy analysts need look no further: The Thorium Fluoride Reactor is ready for business.
Joseph Archer is a professional engineer with a degree in nuclear engineering.
http://www.realclearscience.com/articles/2011/05/19/safe_cheap_nuclear_thorium_fluoride_reactors_106239.html
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