Nuclear Energy To Go

By Roland Piquepaille

Researchers at the U.S. Department of Energy (DOE) are designing a self-contained, tamper-resistant nuclear reactor that can be transported and installed anywhere in the world. In "US plans portable nuclear power plants," New Scientist writes that the sealed reactors would last 30 years and deliver between 10 and 100 megawatts. The largest version would be about 15 meters high and 3 meters wide, with a weight of about 500 tons, allowing for transportation by ships or very large trucks. The DOE thinks that this kind of nuclear reactor -- named SSTAR for "small, sealed, transportable, autonomous reactor" -- would help to deliver nuclear energy to developing countries while significantly reducing the risk of nuclear proliferation associated with the use of nuclear power. What do you think of this idea? Is it a good one or a crazy one? Leaving a nuclear reactor in a developing country which can potentially become unstable during the 30 years of service of the reactor doesn't seem to be terribly safe. Anyway, there will be no prototypes before 2015. Read more...

Here is the introduction from New Scientist.

A nuclear reactor that can meet the energy needs of developing countries without the risk that they will use the by-products to make weapons is being developed by the US Department of Energy.

The aim is to create a sealed reactor that can be delivered to a site, left to generate power for up to 30 years, and retrieved when its fuel is spent. The developers claim that no one would be able to remove the fissile material from the reactor because its core would be inside a tamper-proof cask protected by a thicket of alarms.

But will this be safe and avoid nuclear proliferation?

Known as the small, sealed, transportable, autonomous reactor (SSTAR), the machine will generate power without needing refuelling or maintenance, says Craig Smith of the DoE's Lawrence Livermore National Laboratory (LLNL) in California.

Conventional reactors pose a threat of proliferation because they have to be periodically recharged with fuel, which later has to be removed. Both steps offer operators the chance to divert fissile material to weapons programmes as is thought to have happened in North Korea and Iran.

So these reactors might be safe, except if people in a suddenly unstable country decide to break them to get the plutonium inside.

Now, let's look at practical considerations, such as physical characteristics and availability.

A version producing 100 megawatts would be 15 metres tall, three metres in diameter and weigh 500 tonnes. A 10-megawatt version is likely to weigh less than 200 tonnes.

The US will deliver the sealed unit by ship and truck and install it. When the fuel runs out it will collect the old reactor for recycling or disposal. The DoE hopes to have a prototype by 2015.

Here is one conceptual design of the SSTAR nuclear reactor, enclosed in its transportation cask. "When it is upright, SSTAR will be about 15 meters high and 3 meters wide, and its total weight will not exceed 500 tons. This compact size will allow the nuclear reactor to be transported on a ship and by a heavy-haul transport truck." (Credit: LLNL).

For more information, you can read "Nuclear Energy to Go: A Self-Contained, Portable Reactor," an article published by LLNL in its Science & Technology Review. The illustration above comes from this article.

According to this article, the SSTAR program can also be useful inside the U.S.

In the U.S., the Nuclear Regulatory Commission (NRC) oversees more than 100 nuclear power plants that were built during the 1960s and 1970s. SSTAR would provide a secure and cost-effective system to replace older nuclear reactors as well as aging fossil-fuel plants, particularly in an isolated location.

In this article, the DOE says that these future reactors will run unaltered for thirty years.

The current SSTAR design reduces the potential for a terrorist to divert or misuse the nuclear materials and technology. Nuclear fuel will be contained within the sealed, tamper-resistant reactor vessel when it is shipped to its destination, and the spent reactor core will be returned to the supplier for recycling.

SSTAR addresses proliferation concerns with other features as well. No refueling is necessary during the reactor's operation, which eliminates access to and long-term storage of nuclear materials on-site. The design also includes detection and signaling systems to identify actions that threaten the security of the reactor. And because of the reactor's small size and its thermal and nuclear characteristics, the design can include a passive method to shut down and cool the reactor in response to hardware or control failures.

I'm sure that the DOE people are competent and trustworthy, but as I asked at the beginning of this entry, do you think that the future deployment of such mobile nuclear reactors is safe? Or do you think it's very dangerous?

Sources: Jeff Hecht, New Scientist, September 1, 2004; Gabriele Rennie, Science & Technology Review, Lawrence Livermore National Laboratory, July/August 2004