Clean energy advocates may have noticed that President Obama didn’t just tout solar and wind in this week’s State of the Union address; he also encouraged the construction of new natural gas, clean coal, and nuclear power sites. Natural gas and clean coal aren’t all that clean (that’s for another column), but nuclear may be a decent option. Should we be paying more attention to it?
Nuclear plants produce power by grabbing the energy released from the nucleus of an atom via nuclear fission, a process that splits atoms into at least two nuclei and creates byproducs of heat and gamma radiation (radiation made out of high-energy photons). Fission is triggered by the absorption of a neutron by a fissile atomic nucleus like uranium or plutonium. At the most basic level, the heat generated from this nuclear reactor is used to boil water, which turns a turbine and creates energy.
What makes nuclear power appealing is its lack of emissions and relatively abundant fuel source. There is little shortage of fuel resources for nuclear energy—according to some estimates, for example, there is up to five billion years’ worth of uranium-238, a fuel used in fast breeder reactors. And there is up to four times as much thorium—another fuel used in certain fast breeder reactors—as there is uranium worldwide.
But fuel availability is hardly the biggest problem for nuclear power plants. There’s also the issue of safety. Barring Homer Simpson-like accidents, there are a number of things that can go wrong, including meltdowns, fires, and potential terrorist attacks. The potential damage that radiation can cause has been observed the world over through pictures and video of accident sites like Chernobyl and Three Mile Island.
And then there’s the issue of where to store spent fuel. After radioactive materials have been used in a power plant for a while, they can’t sustain a nuclear reaction any longer and have to be replaced. However, they’re still dangerous and radioactive; so storing them safely and securely is a challenge. The U.S. government proposed using Yucca Mountain, a Nevada mountain near nuclear test sites, as a nuclear waste repository. The plan was scrapped in 2010, and as a result, the country has no long-term plan for nuclear waste storage. Instead, waste is stored on-site at nuclear plants; currently, 70,000 tons of radioactive waste are stored at more than 100 nuclear sites across the United States—a potential safety issue for surrounding communities.
Nuclear power plants aren’t cheap, either. Reactors cost billions of dollars to build, which is why there are only 104 operating in the entire country and why they’re all old—all of these plants began construction in 1974 or earlier. Ground was broken on a South Carolina reactor in 2010, and Obama promised loan guarantees for two new reactors at Georgia Power’s Vogtle LLP plant the same year, but construction has not yet started.
None of this sounds encouraging for the future of nuclear fuel. But there is hope coming from unlikely corners. A startup called TerraPower recently teamed up with Toshiba to develop hot tub-sized reactors that can use depleted uranium as fuel and go up to a century without needing to be refueled. The pair still are searching for building materials that can withstand 100 years worth of radiation. And the Defense Advanced Research Projects Agency is currently soliciting design ideas for reactors that use human waste in addition to radioactive material, which would have the benefit of easily accessible and limitless supplies of fuel.
These advances are far-off, however, and few research initiatives look promising in the near-term. Until we can solve problems of cost, waste storage, and safety, nuclear will remain an enticing but unrealistic option.
Illustration by Sara Saedi
