Nuclear Power

Even though a big power plant can create electricity for an entire city, a power plant is pretty simple inside. There are four major parts. The first part is a gigantic furnace that can burn oil or coal or natural gas to create a blast of heat. The second part is a collection of pipes laced through the furnace. Water flows in the pipes and the heat turns the water into steam. The third part is a big steam turbine. The turbine is a special windmill for steam. The pressure of the steam spins the turbine. And the turbine connects to the fourth part: an electric generator. At a city-size power plant, the generator can create something like 500 or 1,000 megawatts of electricity.

A nuclear power plant works the same way, except for one big difference. Instead of burning coal or natural gas, you create the heat with uranium instead. The reason you can do that is because there are two kinds of Uranium: U-235 and U-238. The difference between U-235 and U-238 is very simple. A U-238 atom has three more neutrons in its nucleus than a U-235 atom does. Everything else is the same. The funny thing is, though, that little difference has a big effect on the way the two atoms behave. U-235 will do something called spontaneous fission, and when they do, they give off a lot of heat.

The word "fission" means "splitting." If you hit a U-235 atom with a flying neutron, it splits into two smaller atoms, throws out several new neutrons, and creates heat. And it creates a LOT of heat -- a lot more than you get, say, by burning a carbon atom. Then the new neutrons hit other uranium-235 atoms and make them split. You can call this a chain reaction, because one splitting atom makes others split, and those splitting atoms make others split, and so on.

This sounds perfect. You mine the uranium, purify it, and then stick it in a nuclear power plant. The uranium contains a HUGE amount of heat; just a few pounds contain the same amount of heat as a million gallons of gasoline -- and a little uranium is cheap by comparison. Furthermore, the uranium doesn't add any carbon to the atmosphere like gasoline does, meaning that a nuclear power plant is much better for the environment. So what's the problem? There are two big problems. The first problem is that the uranium left over after a power plant uses it is still radioactive. And it will be radioactive for thousands of years. Just a little bit of uranium can kill or sicken a lot of people. So you have to store it safely for thousands of years. The problem is, we don't have a safe storage place yet. Then you have to transport the uranium to the storage area, and there is always a chance for an accident. The second problem is that, if something goes wrong at a nuclear power plant, all of the radioactivity can create big problems. A nuclear accident releases radiation from the plant, and the radiation can make lots of people sick. For example, in Russia, a nuclear plant in Chernobyl exploded. It has made thousands of people sick. The closest we’ve come to such an incident in the United States is Three Mile Island – a nuclear power plant that is located near Middletown, Pennsylvania. On March 28, 1979, an accident caused a core meltdown at one of two reactors at the Three Mile Island nuclear power plant. Fortunately, the accident did not immediately lead to any deaths or injuries among plant personnel or residents in the neighboring communities.

So, is nuclear power good or bad? It’s good because it can help cut global warming in a big way. But there are also some risks. If we can figure out ways to lessen the risks, nuclear power can be a very good thing.