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Diving Deeper

Why Nuclear Energy?

Work Area: Advanced Nuclear Energy

The need for a viable expanded nuclear energy option is great. First, global energy demand is expected to grow by at least 50% by 2035, with electric demand in the developing world expected to triple.¹ Presently, more than one billion people lack electricity access altogether, with billions more consuming a tenth or less of the electricity per capita consumed in the OECD; and much of that supply is intermittent.² Abundant, on-demand, 24/7 power is essential to human development and economic growth.

At the same time, ~80% of the world’s energy, and about two thirds of the world’s electricity is derived from fossil fuels.³ In the December 2015 Paris climate agreement, 195 nations adopted a goal of containing global warming to a 1.5-2 degree (Celsius) increase in global average temperature compared to pre-industrial levels. Analysis by the Intergovernmental Panel on Climate Change has determined that achieving this goal will require a global energy system that emits almost no carbon dioxide sometime soon after mid-century.⁴

In turn, nearly every authoritative analysis of the energy technologies required over the next several decades to create a near-zero carbon energy system has concluded that there will likely be a need for large amounts of nuclear energy. Recent reports from the Intergovernmental Panel on Climate Change, the International Energy Agency, the UN Sustainable Solutions Network, the Joint Global Change Research Institute and the Pacific Northwest National Laboratory suggest the world will need up to 1600 GW of nuclear capacity or more by 2035-2050 to meet targets.⁵ Currently, around 450 operating reactors produce just under 400 GW,⁶ with less than 100 producing just under 100 GW in the United States.⁷ In order to meet global climate goals over the next several decades, up to a fourfold increase in today’s global nuclear capacity will be required, and a substantial increase in the global annual rate of deployment (see Figures 1 and 2 below).

Figure 1. Current Nuclear capacity and Nuclear Capacity Needed to Meet Various Climate Target Estimates. (Source: Clean Air Task Force from PNNL, IEA, WNA)
Nuclear build out rate figure
Figure 2. Annual nuclear build rate required to meet various Climate Target Estimates (assuming that half of all current reactors will need to be replaced by 2040). The last bar represents an extrapolation of the French nuclear plant build rate over two decades to the current world as a whole, and normalized by GW installed per unit population. (Source: Clean Air Task Force from PNNL, IEA, WNA)

Meeting these kinds of targets for human development and for climate change will require a substantially different kind of nuclear reactor that is less expensive, faster to realize, and more likely to achieve public acceptance.

Fortunately, the technology is not standing still. Existing nuclear development leaders and dozens of innovative start-up companies are pioneering new or updated designs that could be commercially ready with appropriate business infrastructure and policy support. These designs employ different fuels and reactor technologies that are potentially much safer and more economically viable, faster to build, produce reduced waste, and have a lower proliferation risk.

I. The Potential for Advanced Nuclear Energy

For many reasons, today’s world fleet is comprised predominantly of two families of light water reactors: pressurized water or boiling water reactors. The fleet has realized significant gains in performance and safety system design over the last 40 years and now delivers over 30% of carbon free generation worldwide.⁸ However, today’s conventional fleet has design and operational characteristics that have limited the performance, economic viability, and risk perception of the nuclear industry for the last 40+ years. Advanced reactors have characteristics that may address some of these limitations of the existing fleet.

A. What is “advanced nuclear energy”?

“Advanced nuclear energy,” implies a reactor or fuel cycle that must offer some of the following attributes:

  • lower capital and/or operational costs;
  • manufacturability or rapid deployment capability;
  • passive safety systems;
  • ease of operation and maintenance;
  • reduced emergency planning zones, reduced offsite impact during an accident, and increased flexibility/scalability of siting;
  • increased proliferation-resistance;
  • decreased water use;
  • decreased waste production and/or an actinide management capacity;
  • more efficient use of fuel resources;
  • adaptability for hybrid generation (e.g. hydrogen production, desalination, etc.) and/or load following
  • reduced material inputs.

A single technology may or may not offer all of these improvements; however, the range of technologies that offer some of these improvements is wide, and includes both fission and fusion technologies.

B. How do advanced reactors address these desired attributes?

Capital Cost. Less than 20% of the costs of a conventional light water nuclear plant are connected to the cost of the nuclear reactor itself and power production equipment. Most of the cost comes from the construction of large containment structures, cooling equipment, site infrastructure, and financing costs for lengthy construction times (typically 4-5 years or more, compared with months to two years for a gas or coal plant). While future advanced light water reactors may achieve reduced capital costs, Non-light water advanced reactors can address the cost issues in two ways. First, by eliminating water from the cooling process, using coolants with different characteristics and using inherent safety strategies, the need for large pressurized containment and redundant cooling equipment is eliminated, eliminating as much as two thirds of the total plant mass of concrete and steel. Second, by reducing the complexity and size of the on-site structures needed, most of the advanced plant can be built in a factory or shipyard and delivered to site. This can chop construction times in half, or better; avoiding two years or more of significant plant financing costs. A recent survey of a dozen advanced reactor developers suggested advanced reactor capital costs of roughly a third to half of current large LWR levels, and “nth of a kind” construction times of a little over two years.

Deployment rates. By reducing complexity and enabling faster construction times, deployment rates necessary to counter plant retirements while meeting future climate targets can be achieved. Manufactures such as Boeing produce 600-700 airplanes per year, and the world’s shipbuilders produce dozens of large ocean-going ships each year. Also, because of the enhanced safety and waste characteristics, advanced reactors are likely to need less land, reduced site development, and reduced approval lead time. Some designs, such as certain molten salt reactors, incorporate fail-safe designs such as plugs that dissolve should temperatures in the fuel core rise, draining the fuel into an isolated underground chamber. Additional designs incorporate passive safety features that rely on the natural forces of our world, such as gravity and convection, to achieve enhanced safety.

Waste Management. Light water reactors use less than 5% of the energy value of their fuel, leaving 95% as waste. Many advanced reactors, operating on the fast neutron spectrum, can greatly increase fuel utilization, leaving a much lower waste volume. Moreover, the remaining wastes are far less persistent, with toxicity half-lives of hundreds, rather than tens of thousands, of years. This may allow an engineered solution to waste storage that is safe for centuries vs. a long-lived waste repository requiring certification for millennia.

Weapons Proliferation and Physical Protection. As with current light water reactors, there is always the risk of diversion of nuclear material for illicit purposes such as use in state level weapons development/production or use in a “dirty bomb” by a non-state actor. A potential benefit of advanced reactors is that many designs use fuels and produce waste streams that are not as desirable for diversion. First, because many advanced fuels are not readily accessed (e.g. liquid fuels in a molten salt reactor) and second, because waste streams are often much smaller due to high burnup of fissile material during operation. Ongoing efforts in this area to quantify and assess “safeguardability” must continue apace and must be factored into any regulatory and licensing effort.

Multiple Applications. Current light water reactors are best at producing electricity on a baseload, 24/7 basis. But many advanced reactors are more versatile and can more easily cycle to match fluctuating load, which may become more important as increasing amounts of wind and solar energy are added to global grids. Additionally many advanced reactors produce much higher temperature heat, which can be used for process heat applications in the chemical, refining, food processing, steel industries (whose heat use from fossil fuels accounts for more than 10% of global energy CO₂ emissions), displacing boilers in existing coal plants, and numerous other applications.

CATF has produced a more extensive primer on advanced nuclear energy, in which many of these points are elaborated.

II. Reducing the Cost and Improving the Deliverability of Current Nuclear Technology

While recent U.S. and European experience has shown high costs for first-of-a-kind new nuclear units, many nuclear projects around the world are being built today at a 50 to 80 percent lower capital cost than current and recent projects in the United States and Europe. (See Figure 3 below).

Nuclear capital cost graph
Figure 3: Overnight capital costs of nuclear plants recently built or under construction. Source: ETI, footnote 19, from reported data.

At this cost level, nuclear is competitive with both fossil-fueled sources of electricity as well as many renewable sources, as Figure 4 below shows.

Figure 4: Total cost of electricity production with capital and operating costs included. Source: Lazard, 2017. *Reflects Lazard’s cost estimate for a “PV Plus Storage” unit. These storage costs are assumed to be the same for wind.

A recent study⁹ commissioned by Energy Technologies Institute (ETI 2018) found that the gap between most and least expensive global nuclear project costs is due principally to best in class industrial practice, labor productivity and a strategy to build the same design repeatedly, while maximizing learning between units. The cost reductions had little to do with lower labor rates, build quality or rigor of safety regulation. Similar findings are embedded in the recent MIT report, “The Future of Nuclear Energy in a Carbon-Constrained World.”¹⁰

These best practices are not country-specific. They can be transferred globally and improved upon to further reduce cost and build times. A historical example of this includes how the Toyota Manufacturing System challenged U.S. car manufacturers in the early 1990s. Toyota produced high quality vehicles at much lower costs. Instead of going bankrupt, U.S. companies implemented key parts of Toyota’s approach, both saving their industry and providing the basis by which foreign competitors would later build U.S. factories. A significant part of the higher costs can be indirectly traced back to inexperience and first-of-a-kind (FOAK) projects. Building something for the first time or doing it in a country for the first time (or after a prolonged pause) makes it very hard to implement best practices and high labor productivity – two of the big cost drivers according to the study – throughout the project.

Achieving cost reduction will require significant, internal transformation of the nuclear industry and this must be supported by public policy and continuing RD&D:

Developers and buyers of current water-cooled technology must redesign their process and business model to address the cost reduction opportunities outlined in the study. Examples would include:

  • A commitment to completion of the detailed plant design and the detailed construction planning process before concrete is poured.
  • Unified construction management.
  • Applying best practices for supply chain and labor management, allowing them to carry on experience and learning from one project to the next.
  • An internal, industry “best construction practices” learning organization equivalent to the operational learning facilitated by the Institute of Nuclear Power Operators.

Government must also play a role:

  • Cost reduction should be a major objective of any government sponsored R&D program for nuclear energy. These have typically focused on reactor technology and safety instead of component fabrication, delivery, and plant construction.
  • Any future government support of existing reactors should be contingent on best cost reduction practices having been hard wired into the project.
  • The government should also consider supporting common facilities such as leasing shipyard construction sites for reactor assembly.
  • Harmonization of international licensing to maximize transferability of same designs.
  • More result-oriented regulation to allow for minor design changes without heavy bureaucracy.
  • A clear, long-term energy policy from the federal and state governments is needed. It should include decarbonization targets that include all clean energy sources and allow nuclear energy to play a role. This would help justify the intentional long-term program of learning and improving cost efficiency through best practices in management, organizing manufacturing alliances and building efficient supply chains.

The above analysis applies to current water-cooled nuclear technology. More advanced reactors – typically using non-water coolants – have a variety of different characteristics that could further reduce costs (as well as further improve safety, waste and non-proliferation performance). Specifically, many of these designs involve the following cost control attributes:

  • Reduced construction scope, duration, and labor, particularly at site due to fewer buildings and fewer safety systems needed due to passive safety design.
  • Designed to enable a much higher percentage of factory production of key components and assemblies.
  • Simpler plants design enabling a less labor-intensive Quality Assurance and verification.
  • Highly-standardized, modular designs.
  • Design for design reuse and constructability.
  • Designed-in seismic isolation reduces site specific design costs.
  • Fewer operating staff due to the inherent safety characteristics of the reactor/plant design and fuel type.
  • Some companies are incorporating virtual/remote operation enhancements.

The ETI report and other studies¹¹ find that advanced reactors present the possibility of a step change in cost reduction in EU/U.S. markets compared to conventional design builds in EU/North America – even beyond the reductions outlined in the ETI report for conventional water-cooled reactors.

While these cost reduction initiatives and new designs will not address all the barriers to global nuclear energy expansion, they will make nuclear a far more viable option for decarbonization, and as a result, our decarbonization efforts significantly more efficient.

¹ BP Energy Outlook to 2035

² World population data at:; Electricity access data at

³ Fossil fuel energy consumption at;

⁴ Fawcett, Allen A., et al. “Can Paris pledges avert severe climate change?.” Science 350.6265 (2015): 1168-1169.

⁵ See, e.g., Intergovernmental Panel on Climate Change, Working Group III – Mitigation of Climate Change,, Presentation, slides 32-33; International Energy Agency, World Energy Outlook 2014, p. 396; UN Sustainable Solutions Network, “Pathways to Deep Decarbonization” (July 2014), at page 33; Global Commission on the Economy and Climate, “Better Growth, Better Climate: The New Climate Economy Report” (September 2014), Figure 5 at page 26; Joint Global Change Research Institute, Pacific Northwest National Laboratory, presentation to Implications of Paris, First Workshop, College Park, MD, 4 May 2016 (JGCRI, College Park, MD, 2016);

⁸ BP Statistical Review of World Energy (June 2018), p. 48

⁹ Energy Technologies Institute, “The ETI Nuclear Cost Drivers Report” (April 2018),


¹¹ See Clean Air Task Force, “Advanced Nuclear Energy: Need, Characteristics, Project Costs and Opportunities” (April 2018); See Energy Options Network, “WHAT WILL ADVANCED NUCLEAR POWER PLANTS COST?: A Standardized Cost Analysis of Advanced Nuclear Technologies in Commercial Development “(July 2017),

Have Questions?

To request materials or updates relating to advanced nuclear energy, contact Carlos Leipner, Director of Global Nuclear Energy Strategy