We've all heard the claim: "commercial reactors only come in one size -- extra-large."
At a Washington press conference last week, an old name in nuclear technology hammered yet another nail in the coffin of this misconception.
The Babcock & Wilcox Company (B&W) plans to deploy a North American-manufactured, scalable nuclear reactor using its unique history of more than 50 years of continuous reactor engineering and manufacturing. The B&W mPower reactor design is a passively safe [nuclear reactor, which] would provide customers with practical power increments of 125 MWe to meet local energy needs within power grid and plant site constraints.
As the New York Times noted, B&W touts this new technology as a "potential game changer for the global nuclear market."
A "Game Changer"? So What Is It?
B&W's new design is a light water reactor, a concept that is similar to the 104 nuclear reactors that provide almost 20% of electricity generation in the US today. The main difference between this new design and currently operating reactors is that B&W's concept is much smaller, about 1/8 the size of a conventional nuclear plant. This scaled-down size provides several advantages:
It is modular: The reactor and steam generator components can be manufactured at a North American factory, assembly-line style, and shipped by rail to site. The entire combined reactor/steam-generator unit is small enough to fit on rail cars.
It uses passive safety features: Today's nuclear reactors rely on redundant, engineered safety systems. Although this has been a highly successful strategy, these active safety systems cost money to design, build, and maintain. Newer designs, such as Westinghouse's AP-1000, use passive safety systems -- relying on the laws of physics, rather than an engineered system consisting of pumps, valves, and motors, to provide safety. In general, passive safety systems are easier to design for smaller reactors like the 125 MW mPower, and this design leverages this advantage.
It is flexible: The relatively small, modular design can be deployed in a wide variety of locations. A single unit can be used to supply the electricity for a small city, or the modules can be deployed in groups. A plant consisting of a "six pack" of these modules would produce 750 MW of electricity, which would make it the size of a fairly large power plant. A grouping such as this would have economic advantages as well, since the reactors would be able to share resources, such as generators and auxiliary buildings. The owner of the plant would be able to add additional capacity (in increments of 175 MW) as the demand for electricity increases. Such a staggering of capital investments would reduce financial risk and eliminate one of the criticisms that many fiscal conservatives have levied against new nuclear plants: that they are too risky for Wall Street to finance without government help.
Gee Wiz - Other Nifty Features
The new design has a couple of other interesting features:
- The entire nuclear/steam-generation part of the plant is designed to be located below ground. This has some obvious advantages, such as protection against airplane strikes.
- The reactor is designed to need refuelling only once in every five years. This refueling cycle is over three times as long as the 12 to 18 month refueling cycle used by today's nuclear plants.
- The plant design will include a spent fuel pool that is large enough to store 60 years' worth of used fuel -- i.e., all of the fuel that will be used by the plant during its entire design life. With the uncertainty that exists today when it comes to what will be done with used nuclear fuel -- bury it, recycle it, or whatever -- this is a very practical feature that leaves nothing to chance.
Yet Another Small Reactor?
Press releases about small reactors are nothing new. Several companies have announced plans for building small reactors -- including NuScale, in Oregon, which plans to build small 40 MW modular reactors, and Hyperion, out of Los Alamos, which has its own design for a "nuclear battery" that is about the same size. So what makes this announcement different?
Well, for starters, Babcock & Wilcox is an established company in the nuclear field. Unlike some of the other companies with small reactors on the drawing board, which are startups hoping to capitalize on a single idea or innovative design, B&W has been manufacturing reactors and nuclear components for over 50 years. It has considerable experience manufacturing "small" reactors in the form of naval nuclear reactors for submarines and aircraft carriers.
Furthermore, this company already has facilities that are capable of manufacturing nuclear-grade components. It has not one, but two facilities in Ohio and Indiana that hold the coveted ASME N-Stamp, which makes them two of the few places in North America that can manufacture large, heavy-walled nuclear components and vessels.
This is not just any company that is announcing plans to build small reactors.
So What Now?
Before we get too excited over this announcement, let's take stock of the situation and consider some sobering points.
First of all, as B&W's sales brochure indicates in the footnotes, the mPower rector design is not complete. There is more work that needs to be done before this is a product that is ready to ship. B&W has indicated in its press release that it intends to submit an application to the US Nuclear Regulatory Commission (NRC) for design certification of the reactor in 2011. After that, the review process will likely take a couple of years, so this is a product that will not "hit the shelves" until well into the next decade.
Nevertheless, it appears that B&W is banking on the design being similar enough to currently running power reactors to simplify and expedite the licensing process, which will allow them to bring the product to market sooner than otherwise would happen. Certainly, B&W has a point; there are quite a number of similarities. Like the 104 commercial reactors that are operating in the US today, the new design uses water as both a moderator (to slow down the neutrons) and a coolant (to carry heat energy to the turbines). From what information I've been able to gather on the internet, it appears that the parts containing the nuclear fuel (called "fuel assemblies" in the biz) are almost identical to those that are used in many of today's reactors. They are simply shorter.
These similarities, coupled with a much smaller power level, could greatly simplify the design certification process. This would give B&W a substantial advantage over its competitors in what is becoming an increasingly crowded (potential) market for small commercial nuclear reactor designs.
It is interesting to note, however, that when it comes to competition, time is perhaps on the side of Babcock and Wilcox. Since it is a large company with substantial manufacturing capabilities and an already established, stable revenue stream, B&W is in a good position to retool today to manufacture these small, modular reactors, even while the design is being finalized and certified by the regulator. Thus, once the final hurtles are overcome, it could (potentially) move very quickly into production mode. In keeping with this strategy, B&W has already entered into a deal with the Tennessee Valley Authority (TVA) to evaluate a potential lead plant site for the new reactor.
So is this a "game changer"? Well, I think that it is premature to speculate right now, but there are some encouraging signs. This is an established company, with a long history in the nuclear field and substantial manufacturing capabilities, that has announced that it intends to develop and license a small reactor design. This is very promising news, but there are still many unknowns.
More broadly, however, this announcement gives a clear indication that industry is taking the "nuclear renaissance" very seriously, and even companies that have not been heavily involved in the commercial nuclear reactor business over the past two decades are trying to get into the game with innovative designs.
Finally, this announcement, and others like it, are putting to bed the myth that is often bandied about by paid anti-nuclear propagandists and uninformed renewable advocates: nuclear power only comes in one size -- large. That might be true today, but it most definitely will not be true tomorrow.
If this really turns out to be a game changer, however, I predict that this "game" won't be limited to just the nuclear market. This has the potential to change the game for the entire energy sector. Will it happen? We'll just have to wait and see.