When you hear the phrase “nuclear energy,” you might think of the first use of this dangerous technology – building and detonating the first atomic bomb. The association gives nuclear power plants an ominous connotation. But nuclear power, which is almost always derived from uranium, is also a fascinating and deeply efficient source of fuel. Just one pound of uranium contains as much energy as three million pounds of coal.

Where does Uranium come from?

Uranium is a heavy metal that was originally formed over six billion years ago in one or more supernovae. A supernova is the death of a star. When the nuclear fuel in the core of a star runs out, the core collapses and the rest of the star explodes. As the materials that were part of the star scatter, some neutrons are shaken loose from their atoms. Scientific consensus says that this process created the uranium that eventually found its way into the earth’s crust during our planet’s formation.

The metal can be found in all kinds of rocks and even seawater. But, in order to mine it for fuel, we have to dig for deposits of minerals that have particularly high concentrations of uranium.

How does it create energy?

When you’re talking about an extremely difficult task, you might compare it to “splitting the atom.” Nuclear power plants convert uranium into electricity by doing just that. The energy that eventually powers our homes starts as the energy that holds the atoms in uranium together. Since atoms in uranium are relatively large, it takes less force to split them than it would for other elements. The process starts in a nuclear reactor, where fuel rods full of uranium pellets are placed in water. The reactor essentially burns the uranium until a few neutrons are expelled, and one of them eventually collides with the nucleus of a nearby atom. This causes a chain reaction called fission.

After the uranium atoms split and release their energy, this energy heats water, creating steam. The steam spins a turbine, which powers a generator. The steam then cools back down into water in a condenser to be used again and again. In some nuclear power plants, excess heat is released through a cooling tower.

What’s the environmental cost of Uranium?

Refining uranium and processing it into electricity produces radioactive waste, which can be extremely hazardous to human health and the environment. So, nuclear power plants operate under strict regulations to dispose of the waste safely. The bigger concern among environmentalists is uranium mining. It damages landscapes and ecosystems similarly to coal mining – namely, the removal of mountaintops and release of heavy metals and other toxins into the atmosphere. With uranium mining, there is the added concern of radioactive materials being released into the atmosphere.

The biggest benefit of uranium and nuclear power in general is without a doubt its lack of carbon dioxide emissions. Although disposal of radioactive waste remains a concern, the benefits of a fuel source that does not emit greenhouse gases can’t be overstated.

What are its common uses?

Uranium is mainly a source of electricity, although it also powers some U.S. military submarines. Europe uses uranium-derived energy more widely than the United States, with uranium supplying about 75 percent of electricity in France. In the United States, the use of uranium is more modest, but still significant. There are 104 nuclear reactors in the United States, most of which process electricity from uranium. They produce about a fifth of the country’s electricity.

How much does Uranium cost?

Nuclear power plants are hugely expensive to build, but relatively cheap to maintain. Since uranium is so much more efficient than fossil fuels, it’s considered cost-competitive with other popular sources of electricity.