Ultra-efficient Nuclear Fuels, too Unstable for Use

Nuclear fission reactors produce high amounts of relatively clean electric energy by burning nuclear fuels, such as uranium. Higher-efficiency nuclear fuel is required for the next generation of nuclear reactors, which will burn longer and stronger to produce even higher amounts of energy. However, researchers say that this may prove to be a big problem in case of a critical situation, since this type of fuels could prove to be much more unstable than the traditional enriched uranium.

With high-efficiency uranium fuel, a nuclear reactor power plant could extract several gigawatt-days of energy out of a single ton of nuclear material. Rising fuel efficiency seems to work extremely well with pressurized water and boiling water reactors, albeit rising conversion efficiency is not the sole goal of engineers developing the next generation of nuclear reactors. Radioactive waste is one of the most controversial aspects of using nuclear energy to produce electric power.

Some of these reactors should reach burning rates of up to 60 Gwd/tU, while the nuclear fuel could last one year longer than the uranium fuel rods in nuclear reactors with the best burning rates today, according to the NewScientist magazine.

The problem is that nuclear reactors with burning rates higher than 45 GWd/tU are illegal in the US, due to fuel packaging hazards. If such a reactor were to suddenly lose control over the chain reaction, as in the case of a water loss, the reactor core could suffer a partial or total meltdown. According to the US nuclear energy Electric Power Research Institute, coolant loss is a highly unlikely possibility in the modern nuclear reactors, however a review of the safety standards still has to be conducted in order to evaluate whether high fuel-efficiency reactors will be allowed to function.

As if nuclear waste were not a big enough problem, it seems that the high-efficiency fuels would raise the radioactivity of nuclear waste by 50 percent, comparing to that of waste currently produced in modern reactors. Higher radioactivity, immediately translates into more heat generated during waste storage.