TR: In the next few years, the United States, China, and India, in particular, will turn increasingly to coal. How do we address the massive new carbon-dioxide emissions?
EM: Coal is very important to address because it is a resource located in countries with large and growing energy demand. We envision a “coal refinery” of the future. We talk about advanced fuel conversion technologies to use coal in an environmentally responsible way for multiple products: electricity, liquid fuels, chemicals, and potentially hydrogen. The first task is developing sophisticated modeling and simulation; the second is the laboratory work, such as development of catalysts; and the third would be a set of policy studies, such as how you would transition to a new fueling infrastructure. And sequestration is a critical enabling technology for using fossil fuels in a climate-constrained world. There’s lots of basic science that has to be understood to sequester at a very large scale.
TR: President Bush has been talking a lot about hydrogen. Is the hydrogen economy the answer?
EM: There are many here on campus who have written about it – John Deutch had a Science paper about it and John Heywood has testified to the Congress about it and has written several reports with colleagues. The hydrogen transportation economy looks to us to be very, very challenging, very far off. And “very far off” could mean: forever far off. Given the cost barriers that must be overcome with fuel cells, the challenges for storing hydrogen onboard, and the infrastructure problems for delivering hydrogen – it makes one wonder whether alternative technologies, which require far less disruption to the infrastructure and are far less of a cost challenge, but are highly efficient, don’t essentially accomplish the same goal. But we’re all for research on hydrogen technologies, but not just for the transportation applications.
TR: What research agenda do you propose for nuclear power?
EM: There is no practical alternative to the evolutionary light-water reactor for major deployment within the next 15 to 20 years, because there are no other reactors that are licensed for construction. That alone would take quite a long time. Going down the road, we believe there is certainly a lot of promise in high-temperature gas reactors; and, indeed, an interesting concept is the work at MIT to make the pebble-bed reactor a modular Lego-construction project.
And for the much longer term, there is the vision of fuel recycling. We discuss this kind of research and argue strongly we should start and pursue the research seriously – advanced simulation, new fuels and materials, new separations processes, and the like. But we also note it is certainly a 50-year horizon before advanced fuel cycles that recycle all transuranics [elements with an atomic number greater than that of uranium, such as plutonium-239] might be deployed at significant scale. And these activities also involve significant research into the policy questions. Policy has an enormous influence on whether technologies do or do not get deployed.