Revisiting the Nuclear Option

By Lieutenant William Spears, U.S. Navy

Even if we pursue the lowest up-front price possible, future combat systems may yet drive us to the atom as a matter of practicality. Emerging technology like high-powered radar, electromagnetic railguns, and directed- energy weapons portend a steadily increasing need for electrical power, and a reactor may be the only practical way to deliver that. Operational capabilities like speed and endurance are added bonuses of nuclear power in this case. Despite the high capital investments required or the bureaucratic complications involved in fielding it, nuclear power is a thoroughly proven, cost-effective option for future surface combatants, and we’d be foolish not to seriously consider it.

Yes, We Have Been Here Before

The United States commissioned a total of nine nuclear-powered cruisers (CGNs) throughout the Cold War, beginning in 1961. These vessels were designed as carrier escorts, the combatant muscle in Admiral Hyman G. Rickover’s vision of the all-nuclear carrier battle group. When the Aegis combat system came on line, a massive nuclear-powered strike cruiser was envisioned to field it, but its high cost estimates led decision makers to the fossil-fueled Spruance hull, creating what would become the Ticonderoga class. 2 A lack of committed production runs kept the CGN prices high as the Aegis revolution happened without the participation of nuclear power. The last of the CGNs, the USS Arkansas (CGN-41), was commissioned in 1980.

In addition to being more expensive to build, nuclear cruisers were costlier to operate than their fossil-fueled counterparts. They required pricey maintenance that only nuclear-certified shipyards could perform and spent more time in the yards in general. 3 Even more costly was the manning: almost 600 personnel, many of them nuclear-trained, as opposed to the Ticonderoga ’s 350-odd conventional sailors. Oil had become cheap by the mid-1980s, nullifying the argument for nuclear power as an economical alternative.

The CGNs’ powerful advantages in speed and endurance were never fully realized, as they were usually in the company of fossil-fueled elements of carrier battle groups. They also lacked the advanced antiair/missile or antisubmarine technology of the Ticonderoga -class cruisers or the new Arleigh Burke -class destroyers. More expensive and less capable than competing platforms, the CGNs made an easy target for budgeteers in the post-Cold War drawdown. All nine cruisers were deactivated in the 1990s, with the last two, the California (CGN-36) and the South Carolina (CGN-37), decommissioned in 1998.

The Navy’s experience with nuclear-powered cruisers in the Cold War was certainly instructive. In the decades since the last of those vessels were built, however, some conditions have changed markedly. The Navy has learned a great deal about ship design, especially in constraining lifecycle costs through open architecture and efficient manning. The price of oil has risen, and it will continue to be unpredictable. Emerging threats require high-powered combat systems to address them, demanding more frequent refueling of conventional warships. The confluence of those factors could tip the scale in favor of nuclear power.

What Does it Cost?

As required by the 2006 National Defense Authorization Act, the Naval Sea Systems Command (NAVSEA) took a hard look at the cost effectiveness of nuclear power for surface combatants. Its study estimated that a reactor plant would add about $600 to $700 million (in Fiscal Year 2007 dollars) to the price tag of a medium-sized surface combatant. 4 This figure assumed that rather than designing an entirely new reactor and supporting systems, the Navy would use designs from the Ford -class aircraft carrier. 5

Representatives called on the Congressional Budget Office (CBO) to provide a second opinion. In 2011 the CBO published its findings, which levied a number of criticisms against NAVSEA’s estimate. Foremost among them was that NAVSEA had not conducted a present value analysis, which considers the difference in value between a dollar today and the same dollar at some point in the future; in other words, the “time value of money.” Under a present value analysis, front-loading the ship’s fuel costs into its initial procurement is more costly overall than paying out the same expense over the life of the ship. 6

The CBO estimated that nuclear propulsion for destroyers would require a new reactor design, effectively adding $1.1 billion (FY11) to the price of each ship. For large amphibious-assault ships, which could accommodate the reactor of the Ford class, the CBO estimated the additional expense at $900 million. 7 Both the CBO and NAVSEA assumed that nuclear surface combatants would have life-of-ship cores, obviating the need for costly mid-life refueling overhauls.

In calculating life-cycle costs, both organizations accounted for expenses particular to nuclear-powered ships such as the specialized maintenance, highly skilled operators, and environmental considerations in deactivation and disposal. As nuclear operators are especially expensive to recruit, train, and retain, manning will be one of the most significant drivers of life-cycle costs. Both assumed that a nuclear ship would demand more man power than a fossil-fueled variant, but to a lesser degree than was seen with the Cold War CGNs owing to recent advances in efficient manning. Neither organization believed that additional training infrastructure would be necessary, as the powerful organization Naval Reactors has clearly stated its existing pipeline can support future classes of nuclear-powered ships without new investments in capacity. 8

Since the objective of these studies was to determine the cost-effectiveness of nuclear power in comparison to fossil fuels, both organizations conducted break-even analyses considering the trajectory of oil prices. According to NAVSEA’s analysis, the break-even point for nuclear power is probably between $115 and $225 per barrel of oil, depending primarily on the ships’ operational demands. 9 While lacking the technical granularity of NAVSEA’s analysis, the CBO’s study was more sophisticated from a financial standpoint. It concluded that nuclear power will become economical if real (inflation-adjusted) oil prices grow by an average of 3.4 percent annually, implying a price of $223 per barrel (in 2011 dollars) by 2040. 10


Aside from the obvious hurdle of high capital investment, nuclear power introduces many moving parts to an already complex system. Public opinion, for example, becomes a serious concern, especially in the wake of the 2011 Fukushima disaster. Over 150 ports are available to nuclear vessels, but some of them attract anti-nuclear movements and associated protests. 11 Even in a port that welcomes nuclear vessels, concerns regarding security, firefighting, risks of collision, and proximity to civilian populations will each acquire new degrees of importance.

Nuclear power also multiplies bureaucratic complexity. A traditional design maxim is that a camel is a horse designed by committee. In shipbuilding, a nuclear reactor adds many voices to the committee. That prospect alone is enough to steer planners away from the nuclear option; that the voices belong to Naval Reactors adds an emotional element. Students of the Cold War will recall the costly power struggles between Admiral Rickover (who led Naval Reactors for over 30 years) and his political adversaries, of which the nine CGNs were both a product and a casualty. The shadow of Rickover still looms over any decision that would expand Naval Reactors’ influence, especially within the predominantly non-nuclear surface warfare community.

Another thorny issue is the question of who would build a nuclear surface combatant. Currently two shipyards are certified to construct nuclear-powered ships: Electric Boat and Newport News Shipbuilding. Building nuclear surface ships exclusively at these yards is one possibility, even considering the busy schedule of submarines and aircraft carriers already in progress. The other two major shipbuilders, Ingalls Shipbuilding and Bath Iron Works, have significant experience in building surface combatants that could be of value. Ingalls performed nuclear work in the past, but dismantled that capability in 1980. 12 Certifying either of them for nuclear construction today would involve a substantial investment in facilities, equipment, and training. The CBO estimated this cost at $500 million. (Certifying a third nuclear shipyard was one of the assumptions in their estimate.) 13

The third option is to build the ship in sections, with the engineering spaces constructed by nuclear-certified shipyards. These shipyards would also have to perform the final assembly in order to support nuclear testing and sea trials. 14 Given the success demonstrated by the Virginia program in a shared approach to construction, as well as the political attractiveness of this approach, it is probably the most viable option. That said, lawmakers may consider a third nuclear-capable shipyard to be a national asset of strategic value worth the additional expense.


The NAVSEA and CBO studies were both principally interested in the economics of nuclear power as compared to fossil fuels. Neither study attempted to put a dollar value on the operational capabilities delivered by nuclear power. Seeing as we buy ships to operate them, those capabilities are the most important part of the discussion.

The most obvious benefit of nuclear power, which has been thoroughly exploited by submarines and aircraft carriers, is endurance. Nuclear vessels must still replenish food and spare parts, but the removal of fuel as a limiting factor simplifies replenishment and prolongs time on station. Without the need to refuel, ships may exercise more selectivity in ports of call, lessening the dependence on questionable harbors where terrorist attacks are an elevated concern.

Nuclear vessels are also fast. A reactor plant can produce incredible horsepower for its size, and with the right propulsion machinery this horsepower translates into very high top speeds. Furthermore, while all ships experience sharp penalties in fuel economy at higher speeds, the effects of that penalty aren’t realized until the end of a nuclear ship’s life. In the timeframe of crisis or even a prolonged war, nuclear powered ships can sustain their top speeds indefinitely. This provides flexibility to operational planners, as the ability of nuclear vessels to surge quickly to distant theaters permits a wider distribution of ships to cover potential “trouble spots.”

Short-term indifference to fuel economy has other tactical implications, especially considering the rising trend in power demands of advanced sensors and weapons. Conventional warships must always consider the where and when of the next refueling. If regular access to oil comes into question, ships with power-intensive systems may come under pressure to operate for prolonged periods at reduced speed or intermittent alertness in the interest of conserving fuel.

Another important consideration is the vulnerability of oil supply lines. Politicians in favor of nuclear propulsion regularly cite our military’s dependence on imported oil. That is not particularly relevant since warships only account for eight percent of the DOD’s overall oil consumption. 15 The Navy’s dependence on a network of huge fleet oilers for underway replenishment is more significant. In a shooting war with a capable adversary, these oilers will make inviting targets for enemy submarines or antiship cruise missiles. We will still use them as long as the majority of our surface forces burn fossil fuels, but even a small inventory of warships that doesn’t rely on oilers would make such an attack less attractive for adversaries.

The real question, then, is not just one of economics. We may presume for the purposes of argument that, either due to unaccounted-for costs or a long-term low price of oil, nuclear power will be more expensive in the long run than fossil fuels. That additional expense brings great capability, and it is the value of that capability we must assess. A nuclear-powered warship can transit at flank speed persistently, with its combat systems at full alertness and no immediate concern for fuel economy. What is that capability worth in peacetime? What is it worth in war?

The Technology is Ready When We Are

Nuclear propulsion is not a flashy new concept with dubious promises to revolutionize the mechanisms of seapower. It already did that in the 1950s, and we’ve relied on it ever since, steadily refining our international lead in the technology. It has revealed its limitations, and it has thoroughly proven its capabilities. It makes no pretense of being easy or cheap.

A nuclear-powered surface combatant would be nothing short of a capital warship. That phrase alone, suggesting an irrational nostalgia for the battleship Navy, will provide easy fodder for critics of the concept. Put bluntly, a new ship class of this scale is not realistic in the near term. For the time being, Navy leaders will have their hands full just trying to make ends meet while limiting cuts in force structure. What is unaffordable today, though, may be the most practical answer to a critical weakness tomorrow. Budget conditions, like the terms of peace between superpowers, can change overnight.

1. Patrick Dallosta and Thomas Simick, “Designing for Supportability,” Defense AT&L , March/April 2012, 34.

2. Norman Polmar, “More Nuclear-Powered Ships,” U.S. Naval Institute Proceedings , vol. 133, no. 2 (February 2007), 86.

3. Ibid., 87.

4. Naval Sea Systems Command, “Alternative Propulsion Methods for Surface Combatants and Amphibious Warfare Ships,” Washington, DC, March 2007, 31.

5. Testimony of Navy Officials to the Seapower and Expeditionary Forces Subcommittee of the House Armed Services Committee, 1 March 2007.

6. Congressional Budget Office, “The Cost-Effectiveness of Nuclear Power for Navy Surface Ships,” Washington, DC, May 2011, 9.

7. Ibid., 10.

8. Spoken testimony of Admiral Kirkland Donald before the Seapower and Expeditionary Forces Subcommittee of the House Armed Services Committee, 1 March 2007.

9. Ibid., 42.

10. Congressional Budget Office, “The Cost-Effectiveness of Nuclear Power for Navy Surface Ships,” 7.

11. Spoken testimony of Admiral Kirkland Donald before the Seapower and Expeditionary Forces Subcommittee of the House Armed Services Committee.

12. Ronald O’Rourke, “Navy Nuclear-Powered Surface Ships: Background and Issues for Congress,” Congressional Research Service, Washington, DC, 18 January 2011, 8.

13. Congressional Budget Office, “The Cost-Effectiveness of Nuclear Power for Navy Surface Ships,” 11.

14. O’Rourke, “Navy Nuclear-Powered Surface Ships,” 15.

15. A. Michael Andrews, Walt Bryzik, Richard Carlin, et al., Future Fuels, Naval Research Advisory Committee, , April 2006, 19.

Lieutenant Spears is an active-duty submarine officer, a 2008 graduate of the U.S. Naval Academy, and a 2014 graduate of the Naval Postgraduate School. He is currently enrolled in the Submarine Officer Advanced Course in Groton, Connecticut.


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