Jacopo Buongiorno and others say that transporting factory-built microreactors to the point of use can be a safe and effective option for decarbonizing the power system.
We may be on the brink of a new paradigm in nuclear energy A group of nuclear experts recently made recommendations in The Bridge magazine of the National Academy of Engineering. They say that just as large, expensive, centralized computers give way to today’s widely distributed PCs, a new generation of relatively small and inexpensive factory-built reactors is about to emerge, designed for stand-alone instantaneous applications akin to insertion of extra large batteries. Plug and play operation.
These proposed systems can provide heat for industrial processes or power for military bases or communities, operate without supervision for 5 to 10 years, and then return to the factory for renovation. Authors: Jacopo Buongiorno, professor of nuclear science and engineering at MIT Tokyo Electric Power Company; Robert Frida, founder of GenH; Steven Augier of the Idaho National Laboratory; and Kevin Chilton, retired commander of US Strategic Command nuclear batteries. “The researchers say that due to their simple operation, they can play an important role in decarbonizing the global energy system and preventing catastrophic climate change. MIT News asked Buongiorno to describe his group’s proposal.
Question: The idea of a small modular nuclear reactor has been debated for several years. How is this nuclear battery proposal different? A: The unit we describe takes the concept of factory build and modularity to the extreme. Previous proposals have studied reactors in the 100 to 300 megawatt power output range, which are 10 times smaller than traditional big beasts (large nuclear reactors in the gigawatt class). These can be assembled from factory-manufactured components, but they still require some on-site assembly and a lot of on-site preparation. So it is an improvement of traditional plants, but not a great improvement.
Due to the physical size of these machines, this concept of nuclear batteries is indeed different: about 10 megawatts. It is so small that the entire power plant is built in a factory and packed in a standard container. The idea is to put the entire power plant, including a microreactor and a turbine that converts heat into electricity, in a container.
This provides several benefits from an economic point of view. You are completely decoupling your project and your technology from the construction site, which has been the source of all possible schedule delays and cost overruns for nuclear projects for the past 20 years.
Then it becomes an energy on demand. If customers need heat or electricity, they can get it in months or even weeks, then plug and play. This machine arrives at the place, a few days later, you start to gain energy. Therefore, it is a product, not a project. This is how I like to describe it.
Question : You mentioned that these devices can be widely distributed, even in residential areas, to provide electricity to the entire community. How confident are people in the safety of these plants? A: It is very resistant, this is one of its selling points. First, the fact that it is small is good for many reasons. On the one hand, the total amount of heat generated is proportional to the power, and the power is very small. But more importantly, it has a high surface area to volume ratio, because again, it is small, which makes it easier to keep cool in any situation. It is passively cooled to the point where it does not require anyone to do anything.
You don’t even need to open a valve or anything. The system will handle it by itself.
also has a very strong containment structure, which surrounds it to prevent any radiation release. Instead of the traditional large concrete dome, the steel shell basically encapsulates the entire system. In terms of security, in most sites, we believe that these sites will be below ground level. This provides some protection and physical security for external attackers.
As for other safety issues, you know, if you think of the famous nuclear accidents, Three Mile Island, Chernobyl, and Fukushima, these three issues are all mediated through the design of these nuclear batteries. Because they are so small, it is basically impossible to get that kind of result from any sequence of events.
Question: How do we know that these new reactors will work, and how to make such devices widely available?
A: NASA and Los Alamos National Laboratory conducted a similar demonstration project, which they called a microreactor, for space applications. They only took three years from designing to manufacturing and testing. They spent 20 million US dollars. It is several orders of magnitude smaller than traditional large-scale nuclear power plants. Traditional large-scale nuclear power plants can easily cost more than a billion, and will take ten years or more to build.
Now there are different companies that develop their own designs, and each one is a little different. Westinghouse Electric is already working on a version of this nuclear battery (although they don’t use the term), and they plan to run a demonstration device within two years.
The next step will be to build a pilot plant in a national laboratory that has a large number of nuclear reactor systems test equipment, such as the Idaho National Laboratory. They have a lot of facilities that are being modified to accommodate these microreactors and they have an extra layer of safety. Because this is a demo project, you need to make sure that if something happens that you didn’t anticipate, you don’t release anything into the environment.
The factory can then go through accelerated test procedures to withstand more extreme conditions than those encountered in normal operation.