The Myth of Dangerous Nuclear Energy

June 22nd, 2008 | by blank89 |

In a world where the price of gasoline is soaring, the cost of electricity is also rising. The demand for clean, cheap electricity is huge. One alternative that is the source of much unwarranted controversy is the nuclear option. While not perfect (due to nuclear waste), nuclear energy provides a carbon free alternative to fossil fuel based power plants. However, many people still live in fear that more wide spread nuclear reactors would produce many more incidents like Chernobyl or Three Mile Island. The truth is that while mistakes have been made in the past, they were all easily avoidable.

This article will examine three critical nuclear reactor failures and rate those plants with the standards used in modern nuclear facilities. The mistakes made in past nuclear reactors are largely due to lack of experience or carelessness at all levels of management, from the policy makers to the plant operators.

Three Mile Island

Three Mile Island (Public Domain)

In 1979, Unit 2 of the Three Mile Island nuclear power plant failed when a line pumping cold water to the core stopped working. Heat generated by the nuclear reaction began to build up in the core. Several systems put in place to monitor the reactor coolants failed at once, including two of the three coolant backup lines designed to replace the original broken cold water feed. Combined with human error, these factors prevented proper cooling of the core. At some critical point, the core began to melt. Operators ignored several warnings of coolant loss. It took 9 hours before cooling systems worked again, at which point the core was damaged. A further mistake was made when steam with trace amounts or radioactivity were vented in to the atmosphere.

Since the incident, many safety regulations have been reviewed. More back up systems have been automated, not leaving the option for bad decisions up to plant operators. Drill and test frequency increased, as well as the depth of testing.

Monju Nuclear Reactor

Inside the Monju Reactor (Wikileaks)

In 1995 the Japanese Monju reactor was shut down when one of the sodium coolant lines burst, venting sodium on to the ground below. No radiation was released, because the line that burst was not the primary coolant line. The main problem with this incident was that it was mostly covered up until recently. Public awareness of nuclear accidents is key to preventing carelessness within the industry.

The operation status of all nuclear power plants in the United States, both active and inactive is public information. A list of reactors and their license information is available at http://www.nrc.gov/. There are also ways to report dangerous activity directly to organizations that can investigate directly. There have been improvements in the safety of sodium cooled reactors, but most reactors now use water, due to the reactive properties of sodium and other liquid metal coolants. Sodium generates heat when it comes in contact with oxygen, and also picks up a large amount or radioactivity.

Chernobyl

Ther Chernobyl Reactor (Soviet Authorities)

Perhaps the most well known nuclear disaster (definitely the worst), Chernobyl was easily preventable. Chernobyl was a direct result of the corner cutting techniques implemented by the Soviet government. Not only had recent improvements to safety equipment not been properly tested, but there was no containment building. Safety systems were turned off which would have shut down the reaction so that a test could continue. The test was conducted in poor circumstances on a reactor that was badly designed.

Control rods used to slow down the reaction in case of emergency, and to control the reaction in normal circumstances were poorly designed in such a way that caused a temporary increase in temperature. The rods took up surface area in the core that would normally be used for coolant, and did not speed the reaction down fast enough to compensate. When both the automatically controlled and manually controlled rods were pushed in to the core at the same time, the amount of coolant was not enough to prevent a rapid increase of temperature. In fact, this flaw in the reactor design was already known. Procedure had not been updated to reflect the dangerous series of actions that caused an explosion in the reactor.

Sources

Three Mile Island Accident, Monju, Chernobyl Disaster, Coolants for Nuclear Reactors, Fact Sheet on the Three Mile Island Accident, The Monju Nuclear Reactor Leak, The Sequence of Events and the Causes of the Nuclear Accident at Chernobyl