Small Modular Reactors Speaking in Foreign Tongues

Highly touted by the U.S. nuclear industry and heavily funded by the U.S. government, small modular reactors have largely entered the realm of mythology in this country, slipping into the mists of economic impracticality. Not so elsewhere in the world, where some real projects are under way.

Almost a year ago, workers began pouring concrete for the basemat of the first small modular reactor (SMR) in the western hemisphere. Despite the hype over SMRs in the U.S., with hundreds of millions of Department of Energy dollars available in a competition among several deep-pocketed private-sector nuclear reactor designers over the past several years, the concrete was not flowing in the U.S. It was in Argentina.

Argentina’s National Atomic Energy Commission (CNEA) is building a 25-MW unit—known as CAREM or Central Argentina de Elementos Modulares. It is a small, integrated, pressurized-water reactor some 60 miles northwest of Buenos Aires at the site of the country’s two-unit Atucha nuclear plant (Figure 1). CNEA says the CAREM unit, with a capital cost of $446 million, should begin cold testing in 2016 and go critical in 2017. Given Argentina’s past experience with atomic power, that schedule may well be optimistic. But the country is clearly on a path to developing an SMR far ahead of the better-financed U.S. industry.

1. Groundbreaker. Last year, Argentina became the first nation to begin construction of a small modular reactor with its 25-MW CAREM design at the Atucha nuclear plant. Courtesy: National Atomic Energy Commission of Argentina

The Argentines are justly proud of the accomplishment so far. Norma Boero, CNEA chairman, said at the ceremony for the concrete pour last February, “Although there are other similar reactor projects in the world, this is the first to start construction, which is a pride not only for the nuclear industry but for all Argentinians.”

Small Reactors, Big Hopes

What are small modular nuclear reactors? Most analysts look at machines with nameplate capacity of 200 MW or less as the basic characteristic of the SMR. The plants are also designed to be capable of scaling up by adding additional units, and to be factory-fabricated with components shipped to the construction site, not the historical stick-built, one-of-a-kind plants (see “When It Comes to Nuclear Plants, Is Small Beautiful?” in the December 2013 issue).

According to the International Atomic Energy Agency (IAEA), some 40 SMRs are either under construction or have conceptual or detailed designs around the world, with five of those in the United States. But the U.S. has fallen well behind in this field. In addition to Argentina, which plans a 100-MW plant if CAREM 25 works well, the leaders in the SMR game are, in no particular order, Russia, China, and South Korea.

Two months after concrete began hardening in Argentina, China Nuclear Engineering Corp. (CNEC) began pouring the basemat for a demonstration 2-x-105-MW high-temperature gas-cooled reactor in Shandong province. Construction began a week later. World Nuclear News reported, “Another 19 of the small modular reactors could follow.” CNEC is bullish on SMRs to supply power in vast areas of the country that are now beyond the reach of the Chinese electrical grid.

Russia has pursued small reactors for a long time, and its KLT-40S is a unique approach to the technology. Long under development, this 2-x-35-MW light-water reactor project is a barge-based, floating nuclear plant. The first iteration is the Akademik Lomonosov, scheduled to be delivered to the Rosenergoatom nuclear utility late next year. The project has been under way for nearly a decade, accompanied by hints of scandal, a shipyard bankruptcy, and a cost by official Russian estimates of $239 million—which some observers suspect is seriously understated.

Perhaps the most ambitious SMR program can be found in South Korea, which calls its 100-MW design the System-integrated Modular Advanced Reactor, or SMART, designed by the Korea Atomic Energy Research Institute (KAERI). According to an analysis by the World Nuclear Organization (WNO), KAERI’s design could also be used for desalination, producing 90 MW of electricity along with 40,000 cubic meters/day of freshwater. The design has won standardized approval from Korea’s nuclear regulator, which Korea Electric Power Co. touts as a selling point in its literature (see sidebar). WNO commented, “While the design is complete, the absence of any order for an initial reference unit has stalled development.” KAERI has said it wants to build a demonstration plant to operate in 2017.

South Korea’s SMART Approach to Small Modular Reactors

South Korea began the conceptual design for its System-Integrated Modular Advanced Reactor, or SMART, in 1997, with the basic design completed in 2001 (Figure 2). The design firmed up and was developed and components tested over the next decade, with the Korea Atomic Energy Research Institute (KAERI) spending some $300 million and 1,500 person-years on the project, which won approval from the Korea Institute of Nuclear Safety, the government’s nuclear regulator, in mid-2012.

2. SMART design. South Korea’s 300-MWt SMR design could be up and running by 2017. Courtesy: Korea Atomic Energy Research Institute

The approved design is for a 300-MWt reactor, with up to 100 MW in electrical output. It is also suited for thermal applications such as desalination.

According to the World Nuclear Organization, SMART’s design life is 60 years, fuel enrichment is 4.8%, and the design features a three-year refueling cycle. As in many SMRs, the residual heat removal is passive. According to KAERI, the passive heat recovery design gives the plant a “20 days grace period against Fukushima-type accidents.”

In the design, all fuel is submerged in water and the containment building can withstand a crash from a Boeing 767. The containment also includes a passive hydrogen removal system to prevent hydrogen explosions.

Long History

Small reactors are familiar to the nuclear industry, which began with small machines that bulked up over the years to take advantage of economies of scale. The legendary Shippingport nuclear plant in western Pennsylvania, the first fully commercial pressurized-water nuclear plant, entered service in 1957 and was rated at 60 MW. The U.S. military and the Soviet Union spent considerable sums in the 1950s and 1960s on designs for small, transportable, remote reactors and for reactors to be used in ship propulsion.

Many of today’s SMR plans have their roots in naval reactor technology, as did Shippingport. Its technology was based on Westinghouse reactors that powered the first U.S. nuclear submarines. Argentina’s CAREM 25 reactor design came from the Argentine navy. The country unveiled the design at a 1984 IAEA conference. The project then got shelved, but was revived in 2006 as Argentina moved to revitalize its nuclear power program in the face of limited supplies and high prices for imported natural gas. Argentina has few easily accessible indigenous energy resources.

Russia’s floating nukes also rely on maritime technology, reactors developed for its successful fleet of nuclear icebreakers, dating back well into the days of the Soviet Union. The nation’s first nuclear icebreaker, the NS Lenin, was launched in 1957, the same year that Shippingport went into commercial service.

In the U.S., two of the major SMR industrial developers, Babcock & Wilcox and Westinghouse, both have extensive experience with naval reactors. But that technology advantage has not provided commercial leverage, as both companies have scaled back their SMR programs in the face of a lack of demand for their product (see “What Went Wrong with SMRs?” in the September 2014 issue).

Short on Results

What accounts for the inability of the U.S. (and European, for that matter) market to embrace SMR technology, when less-developed and less–financially muscular countries and utilities are moving ahead?

Giorgio Locatelli of the UK’s University of Lincoln, who published a recent paper on the economics of SMRs, “Small Modular Reactors: A Comprehensive Overview of Their Economics and Strategic Aspects,” argues that the smaller reactors make sense in developing countries, where “it can be very tricky to get equity to make the investments. But with a small modular reactor, you build the first one, which comes cheaper, and then when you’ve raised more money you create the second, and then you start to sell electricity with the first and the second, and by selling electricity you can finance the construction of the third and then the fourth.”

He contrasts that with the mammoth£16 billion ($25 billion) Hinkley Point nuclear project in the UK. “If you are building a nuclear reactor with£16 billion investment and then you decide not to go ahead with the infrastructure and stop it, you have£16 billion in funds that you are not able to recover. If you have a small modular reactor, the financial risk is reduced.”

So why have the U.S. and the Europeans not been successful with SMRs? Locatelli pointed to natural gas, noting the low cost. “The point is,” he said in an interview with, “that if you build a combined cycle gas power plant, it is very easy and cheaper to build and if the gas is cheap it is also cheaper to operate.”

Veteran nuclear power observer Chris Paine of the Natural Resources Defense Council, after attending an SMR conference in Washington last year, noted another problem with the economics of SMR projects, regardless of where they are located. “Nuclear reactors,” he wrote, “historically have evolved to very large single-unit sizes in order to distribute the very large initial fixed capital costs of nuclear power over a larger base of electricity sales, or put another way, to reduce the fixed capital cost requirement per megawatt-hour of electricity produced. But a multi-unit SMR inverts this economic logic, producing fewer kilowatt hours from a larger physical capital investment per unit of capacity.”

Outside the developed world, the economics are often different, or even irrelevant, with state-supported projects, state-monopoly companies, and generally streamlined regulatory regimes dominating the economic and political environment for nuclear power. In countries such as Argentina, China, Russia, and South Korea, the seller of the technology and the buyer are essentially the same, just wearing different hats.

Murky Future

University of Lincoln’s Locatelli noted that it will take a “first mover” to get the SMR market off the ground, and that’s likely to come from outside the U.S. “Historically,” he said, “all nuclear reactors have looked great on paper, but when they start to be built, there could be trouble. So with some designs there was massive cost escalation, which is an issue for a private utility, but if someone starts to build the reactor and proves that it is possible to build on time and on budget, then other utilities can be more confident in their investment. At the moment, every utility is waiting for someone else to be the first to build.”

Where might the first mover be located? “If I was going to bet,” said Locatelli, “they will build one in South Korea and the goal there will be to prove that they can build faster and safer and then they can export. Another one will probably come up in Russia, but it is a very peculiar market that is not open like the United States.”

Of the two-score SMR projects that the IAEA is tracking, few are likely to see the lights come on from their output. Twenty-three are in either the “conceptual design” or “basic design” categories, and only three are actually under construction. The remainder are classified as “detailed design.” If history is a guide, many will fail moving forward. That has long been the pattern with nuclear technology, where only light-water reactors (LWRs), Canadian heavy-water machines, and a handful of Soviet-period graphite-moderated Chernobyl-style machines evolved from the early days of design into the world of generating commercial power.

The list of aspiring SMRs embraces a range of technologies that includes conventional LWRs, fast-neutron reactors, heavy water–moderated technologies, high-temperature graphite reactors, sodium-cooled fast reactors, lead-cooled fast reactors, and lead-bismuth-cooled fast reactors. It is doubtful that any of the more exotic technologies will get beyond engineering drawings.

Perhaps the most practical judgment comes from the late Admiral Hyman G. Rickover (1900–1986), the father of modern nuclear power technology, who was quoted in an analysis of SMR technologies by the WNO. In 1953, about the time the first U.S. test reactor started up, and two years before the launch of the U.S.S. Nautilus, the first atomic submarine, Rickover, an engineer to his core, said:

An academic reactor or reactor plant almost always has the following basic characteristics: (1) It is simple. (2) It is small. (3) It is cheap. (4) It is light. (5) It can be built very quickly. (6) It is very flexible in purpose. (7) Very little development will be required. It will use off-the-shelf components. (8) The reactor is in the study phase. It is not being built now.

On the other hand a practical reactor can be distinguished by the following characteristics: (1) It is being built now. (2) It is behind schedule. (3) It requires an immense amount of development on apparently trivial items. (4) It is very expensive. (5) It takes a long time to build because of its engineering development problems. (6) It is large. (7) It is heavy. (8) It is complicated.

The tools of the academic designer are a piece of paper and a pencil with an eraser. If a mistake is made, it can always be erased and changed. If the practical-reactor designer errs, he wears the mistake around his neck; it cannot be erased. Everyone sees it. The academic-reactor designer is a dilettante.

Little that’s happened in the 60 years since suggests Rickover was wrong. ■

Kennedy Maize is a POWER contributing editor.