As the global population grows, we find ourselves facing growing energy consumption needs. In industrialized nations, this translates into rising energy costs to power our homes and businesses. Power outages are a major concern in metropolitan areas that depend on power to meet humanity's most basic needs. For those in poorer nations, we do not even have a way to supply them power. It is hard to believe, but there are still many in the world who are not close enough to a power grid to be connected.
What if there was a way to cut energy costs in half? What if we could eliminate the possibility of power outages in the future? What if we did find a way to supply power to those in even the most remote areas, even though there is no grid close by? What if we did answer these questions and many others? At present, much of the focus is on alternative energy sources such as wind, solar, geothermal, and others. Nuclear power remains a gray area in terms of alternative energy sources, largely due to fears over environmental and safety issues. However, there have been many changes in the way nuclear power is managed and it is much safer now than it was in the past. Currently, there are plans to design small, portable backyard nuclear reactors. This research will explore the possibilities of these reactors as a means to solve many of the world's current energy problems.
Current Design Proposals
The idea of portable nuclear reactors first began to appear in popular media around 2008. In 2009, Popular Mechanics presented the idea to the world with a drawing of what one of these nuclear reactors might look like for the average homeowner. According to the article, the smaller versions are similar to their larger cousins and they would still need to be approved by the Nuclear Regulatory Commission (NRC) (Hise). Since then, interest in nuclear reactors has continued to grow as the realization that we cannot continue to meet our future energy needs becomes increasingly imminent.
Several versions of smaller nuclear reactors are currently on the design table. The first one is the home unit which is the smallest version, providing energy for a single home or building. Designers realize that the average homeowner does not want a cooling tower in their backyard, so the entire units its underground (Hise). There are also plans for slightly larger units that would provide power for around 45,000 homes. These are much smaller than the larger reactors currently in existence and could be built less expensively and could be designed as modular units that are easy to install (Hise). These are the two primary designs that are being considered for approval by the NRC.
According to the World Nuclear Association, smaller nuclear power units cost much less to build and operate than the larger more complex units in existence (World Nuclear Association and Hore-Lacey). A unit is considered small if it is under 300 MWe. It is expected that by 2040 approximately 1000 smaller nuclear actors will be supplying electricity locally to communities (World Nuclear Association and Hore-Lacey).
A big factor in the decision to develop smaller nuclear power plants is cost. The following table compares the cost of alternative energy sources currently being used. It might be noticed that advanced fuel nuclear technology is included in the table for comparison. Advanced nuclear technology refers to technology such as the small nuclear reactors that are the topic of this discussion.
Cost by technology
Source. EIA. Biomass for Electricity Generation. Retrieved from http://www.eia.gov/oiaf/analysispaper/biomass/figure_3.html
As one can see from this graph, advanced nuclear fuel ranks as one of the more costly forms of alternative energy. Two main factors account for these higher costs. The first is the cost for construction of the plant and administrative fees for licensing and such. The other cost driver of nuclear fuel is the cost of uranium enrichment. Nuclear plants also must have redundancy build into them for safety purposes. Next is the problem of nuclear waste disposal. All of this adds up to higher capital cost when compared to other alternative energy forms.
In a cost comparison by Hyperion, makers of the proposed mini reactor, the cost of installing one of their reactors is much lower than that of installing high power electricity transmission lines. Power is produce 100% of the time and the total energy output is more than 15 times that of the world's most powerful wind turbine (Asher). The total cost to build one of these many reactors is 25,000,000 U.S. dollars. According to Hyperion, the main reactor will be able to produce power at the cost of .05/kWh (Asher, 2008). The company currently has a five-year waiting list, largely from the oil and gas industry.
The actual cost of generation is only a rough estimate at this point and we will have to wait until the units are in operation before real figures can be developed. What we do know is that the cost of building small nuclear power plants is about one half of one percent of the cost of building a full size plant. Full size plants take approximately 12 years to build and smaller versions can be up and running quickly. As of mid-2011, Hyperion has approximately 10 billion dollars in orders waiting to be built (Laytner).
What Challenges do Portable Nuclear Power Supplies Face?
Much of the information in this study has discussed small nuclear power plants as opposed to backyard units. However, Hyperion is also producing units being called the "Nuclear Battery" that are even smaller (Fehrenbacher, 2008). One of the key problems that the acceptance of portable nuclear power supplies face his acceptance by the public. When one says nuclear power, unfortunately many immediately think of accidents such as Three Mile Island, or the more recent nuclear disasters as a result of the Japanese earthquakes. Many do not consider the many nuclear power plants around the world that have been operating flawlessly for decades to provide the power that we need.
Of course, the development of these units faces many regulatory challenges and processes that are a normal part of the nuclear industry. Regulations are strict and at any point the project can be halted by the NRC or other necessary government agencies. Safety is always a major concern in the nuclear power industry. Once Hyperion has cleared all of the government hurdles, it then faces the most difficult challenge, which is convincing the public that these units are safe. Gaining the confidence of the public is the biggest challenge that companies face in the development and marketing portable nuclear power units.
What About Waste?
The first thing that comes to mind when someone says nuclear power is waste. One of the most important principles to understand about nuclear power is how it is regulated through the use of a moderator. Two primary mechanisms control the reaction to keep it from proceeding too rapidly, hence becoming a nuclear bomb. The moderator slows down the neutrons being shed by the uranium so that they can be grabbed by other uranium atoms. This is the process of fission and how heat is produced. The coolant keeps the reaction from going too far and serves as a secondary moderator. The fuel being used in the backyard prototype is different from that being used in larger reactors. The fuel being used is uranium hydride (UH3). It is only a low grade fuel, with an enrichment of only about 10% uranium isotope-235. The rest is uranium 238. By comparison, bomb grade uranium is approximately 98% enriched (McDermott). The nuclear reactor that is proposed to provide power via a backyard nuclear reactor could not possibly become a bomb.
In order to turn the fuel used in home nuclear reactors into something more nefarious would require the ability to reprocess, and reenrich the fuel. According to manufacturers, this is nearly impossible and, "you might as well start with yellowcake" (McDermott). In August of 2008 the first portable power unit, produced by Hyperion Power Generation, was sold (McDermott). Small nuclear reactors that can power 20,000 homes generate waste about the size of a football after 8 to 10 years of operation. The waste stream is very concentrated compared to other energy forms such as coal and gas. The waste would be returned to the manufacturer for proper disposal according to NRC regulations (McDermott, 2008).
What is the Current State of the Technology?
One of the key difficulties in this research is that at the present time the technology is still under development. A few companies have designs out, but as a whole the information available is sketchy at best. At present, no academic research could be found on the portable nuclear reactor. Many of them are still in the design phase and those that are under the production are being kept secret by the companies developing them. Once…