Nuclear power: Why the divide in expert views?

Within the large community of scientists who share deep concern over climate change and accept the urgent need to greatly reduce carbon emissions, there is a sharp divide over the future role of nuclear power in the global energy mix. Among these scientists, arguments for nuclear power’s necessity, desirability, dangers, and impracticality abound.

The case for nuclear power as a necessary component of the fight against climate change typically assumes that sun, wind, and increased efficiency cannot meet future energy needs, particularly baseload demand. Those making the case for the desirability of nuclear power emphasize the relatively small amount of land needed to obtain nuclear fuel and site reactors, and the near absence of the pollutants associated with fossil fuel burning during operation.

Those warning of unacceptable dangers associated with nuclear power generation point to accidents at Fukushima and Chernobyl, to increasing threat of nuclear war among nations if more and more nations have the capability to produce weapons-grade isotopes, to stages in the fuel cycle that could be vulnerable to diversion of radioactive material by terrorists, and to potential leakage from spent fuel storage sites. Those arguing that increased use of nuclear power is impractical mainly emphasize its relatively high cost, its lengthy deployment time, and the absence of widespread public acceptance.

To try to determine whether these viewpoints reflect factual disagreements, one of us (Blades) organized an expert “Living Room Conversation.” The objective was to bring knowledgeable people with diverging views together, in a private setting, to talk with each other, learn whether there is common ground on the future role of nuclear power in reducing carbon emissions, and if not, to try to identify the kind of information needed to achieve agreement on key facts. Such small, structured Living Room Conversations are designed to encourage curiosity and listening across political and other differences.

This conversation was held in July. The six conversants included two environmental scientists whose research emphasizes climate change; one has argued that nuclear power is key to an emissions-free future (argument from necessity), and one has argued that the costs will remain prohibitive while alternatives to nuclear power are adequate (argument from impracticality and lack of necessity). The other four participants included one who had expertise on the US electric grid, one who was a radiation protection specialist, and two who were progressive climate action organizers concerned because the trusted experts they have relied on were telling them conflicting stories about the best path forward with regard to nuclear energy.

There were substantial areas of agreement in the conversation beyond consensus about the need to reduce emissions as much as we can, as quickly as we can, and as cheaply as we can, without causing unacceptable impacts on human welfare. There was consensus about the need for reliable baseload power, and for modernizing the electric grid in the United States. There was general enthusiasm for future improvements in energy efficiency to reduce overall demand. And of course there was support for continuing research, particularly on safety issues at all stages of the nuclear fuel cycle, and in the design and performance of small modular reactors.

More interesting, not a single factual disagreement arose during the two-hour conversation. Nobody claimed that waste storage demonstrably poses large and inevitable risks to the public, or that the waste problem has been solved. Nobody claimed that future Fukushimas and Chernobyls are practically unavoidable or that they are virtually impossible with current safeguards. There was really nothing to argue about … except what the future will look like!

Those arguing from nuclear’s necessity or desirability were fairly confident that future costs will drop substantially, that construction can be expedited, and that safeguards can be developed and put in place to insure public safety. Those arguing from the perspective of nuclear power’s dangers or impracticalities believe future costs will remain prohibitive, risks will remain unacceptably high, and baseload requirements can be met without nuclear power. These diverging views of the future reflected, primarily, different wishes, not possession of, or belief in, different facts. A fact checker cannot mend these differences.

The main take-home message from the conversation was the extent to which only unabashed speculation separated the two viewpoints on nuclear: One side speculates that the price will come down, that terrorists can be prevented from intercepting nuclear fuel supply chains, and that expanded nuclear power will not dangerously increase the likelihood of nuclear war; the other side speculates that the price will remain non-competitive, diversion of nuclear materials will remain a serious threat, and public opinion will continue to resist this solution. One side speculates that solar and wind cannot meet future baseload power needs, while the other hopes that a modernized grid that coordinates solar and wind power across regions, new developments in storage technology, and future development of deep, dry-rock geothermal for baseload power will be sufficient.

The issue of baseload supply emerged as particularly in need of further analysis. There is a need for more discussion of possible ways in which greater temporal flexibility in electricity use can be promoted and achieved, thereby lessening the need for a large baseload supply. The future role of baseload geothermal energy looks promising, but far more analysis and discussion of that option are needed. And finally, the vulnerability of nuclear power’s cooling needs to prolonged and intensive heat waves that could make nuclear power unreliable as a baseload electricity supply also deserves more thought.

Six conversants is not very many; we expect that if many such conversations were held today, some areas of factual disagreement could arise. But the conversation left us confident that the major divide over nuclear power stems from differing speculations about two questions: Can the cost of nuclear power and its risks be reduced substantially, and can essential baseload needs be met without it?

Given that differing hopes and fears are what mainly separates the two sides of the nuclear power debate, what should today’s energy policy look like?  The following is our view, not the consensus from the conversation.

Under uncertainty, some seek to minimize the chance of a worst-case outcome, while others favor policy that promotes a best-case outcome. To minimize the likelihood of a worst-case outcome, we might compare a future in which nuclear power has contributed to the outbreak of nuclear war with a future in which the economy is at times severely disrupted by a lack of sufficient base load power. That unhappy choice would compel most people to plan for a non-nuclear future.  To maximize the likelihood of best-case outcomes (safe and affordable nuclear power; solar, wind and enhanced efficiency, with sufficient baseload supply), the much lower land requirement for nuclear power should be compared with the inherent advantages of decentralized energy systems—systems less vulnerable to human error. In this light, a nuclear future is not the clear choice today in either worst or best cases.

Moreover, solar and wind power are rapidly expanding today, but around the world their output is generally far below the level at which inadequate baseload is limiting their use. Thus in the interests of reducing the climate threat, it makes sense now to greatly and rapidly increase investment in the deployment of those technologies, while investing in a modern grid and improved storage technologies.

Further research and development may provide persuasive evidence that baseload power needs can be met in a carbon-free, non-nuclear future. It might also show that both the cost of nuclear power and its hazards can be greatly reduced. Research and development are the only way to replace, with facts, the hopes and fears that currently dominate the debate.