What's in a Kilowatt-Hour?

Energy economics is a complex terrain. Technologies constantly sweep in and out of the landscape, while geopolitical tremors can wreak havoc on supply and demand. Pinpointing costs is even trickier with nuclear energy, where statistics are often shrouded in mystery, in the name of trade secrets or national security.


Out of this foggy landscape has emerged a new tool that promises to root discussions about the cost of nuclear energy in evidence rather than speculation. Over the last two years the Bulletin of the Atomic Scientists has developed the Nuclear Fuel Cycle Cost Calculator, an online interface that provides a nuanced look at the economic costs of nuclear power.


Built with funding from the MacArthur Foundation, and in collaboration with Chicago Harris professor and William E. Wrather Distinguished Service Professor of Astronomy & Astrophysics and Physics Robert Rosner and a team of researchers, the calculator provides a simple gateway into the universe of nuclear economics. A user can slide more than 60 moving scales to tweak inputs like uranium price or reactor construction time, and then watch the expected price shift before her eyes. The calculator also projects the costs of recycling versus disposing of spent nuclear fuel – a subject hotly debated among experts – and reveals that, when all costs are added in, recycling fuel results in consumers paying more per kilowatt-hour.


“It’s completely transparent,” Rosner explains. “You push a button, and out comes the answer.”


Less transparent are the years of scientific effort underlying the project. While serving as director of Argonne National Laboratory from 2005 to 2009, Rosner worked with a team of nuclear engineers to develop the mathematical model at the calculator’s core. The model captured relationships among variables that determine the price of nuclear energy in three different fuel cycles – that is, whether the nuclear fuel is disposed of, partially recycled (also called “mixed oxide,” or “MOX”) or fully recycled – and revealed that the special materials and processes needed to recycle fuel come with high prices.


The model also provides an economic rationale against practices that Rosner worries could result in stolen plutonium, a nuclear material that, due to its low-level radiation, is susceptible to theft. In a MOX fuel cycle, plutonium left over from previous reactions is not disposed of, but instead combined with uranium. The full-recycling process requires special reactors that can be turned into what Rosner calls “plutonium factories” with slight modifications.


The calculator comes at a pivotal time. “As countries around the world assess their energy needs and consider reprocessing spent fuel, it is crucial that they and we understand the costs of such decisions, which can have dangerous consequences,” says Rachel Bronson, executive director and publisher of the Bulletin of the Atomic Scientists. 


Two years ago Rosner mentioned the project to Chicago Harris Lecturer Kennette Benedict, who was serving as director of the Bulletin at the time. “She thought it would be really interesting if we could put this on the web in some way,” Rosner recalls. But that project would require a responsive web interface, with data presets to provide a reliable baseline.


That was when Jeremy Klavans, MPP’14, got in touch. Klavans, who was focusing on energy and environmental policy at Harris, wanted to lend his expertise to a project with a concrete impact.


“The idea was to first find verifiable data,” Klavans recalls. “We wanted to see if, once we put those prices into our model, we got something reasonable and in line with actual energy costs.” But proprietary information from nuclear power companies was difficult to come by. By reaching out to the Department of Energy and other universities, Klavans was able to piece together the necessary information.


With the data in hand, the next challenge was to design a web interface. For Bulletin editor John Mecklin, this meant a welcome opportunity to present the underlying science in a simple, accessible way. “Nuclear power is no longer magic,” he says.


Computer programmer Sam Olofin, SM’08, was brought on board to craft Rosner’s mathematical model into a user-friendly tool. The calculator went live at the beginning of June 2015. Right away, it spurred a vibrant dialogue. “It’s split between people who can’t believe it – asking, ‘Did you include this?’ – to top experts who want to discuss details,” says Mecklin.  


The calculator promises to keep that dialogue rooted in hard data, as readers of all policy stripes must acknowledge the economic realities that the calculator lays bare. “It’s completely consistent with the UChicago approach, which is, ‘Let’s do things on a fact-based basis,’” Rosner says with a smile. “Let’s not make it up.”   


– Jake J. Smith