BEIJING, China - Chinese President Xi Jinping (R) and U.S. President Barack Obama attend a joint press conference in Beijing on Nov. 12, 2014, following their meeting. They agreed to reduce the risk of military conflict and combat climate change. (Kyodo)

Clean Energy Futures and the Role of Nuclear Power

Thanks to a number of factors – natural disasters, the steady flow of increasingly clear and detailed data, and significant new political accords such as the US-China climate consensus from October 2014 – climate change is now very squarely in the public and political debate (The White House, 2014). Many of us, of course, have been arguing that this should have been the case long ago. In my case I am very pleased to have worked as a contributing and then a lead author to the Intergovernmental Panel on Climate Change since the late 1990s’ (IPCC, 2000).

With the scientific consensus now clear that global emissions must be dramatically reduced, by eighty percent or more by 2050, attention is turning to two themes: 1) what is the permissible budget of fossil fuel use? and 2) What are our viable scientific, technological, economic, and political options to power the economy cleanly before mid-century?

On the first question a series of increasingly clear assessments have appeared that document the oversupply we have of carbon-based fuels. In the latest, high-profile paper, researchers Christophe McGlade and Paul Ekins (2015) make clear that Hubbert’s peak – the rise and then decline in a non-renewable resource such as coal, oil or gas – is largely irrelevant to addressing the climate issue. Fossil fuel scarcity will not initiate the necessary transition.

The environmental bottom line is that to meet our climate targets, cumulative carbon dioxide emissions must be less than 870 to 1,240 gigatonnes (109 tons) between 2011 and 2050 if we are to limit global warming to 2 °C above the average global temperature of pre-industrial times. In contrast to that, however, the carbon contained in our global supply of fossil fuels is estimated to be equivalent to about 11,000 Gt of CO2, which means that the implementation of ambitious climate policies would leave large proportions of reserves unexploited.

There have been several recent calls from people and organizations concerned about global warming to use nuclear electricity generation as part of the solution. This includes The New York Times, the Center for Climate and Energy Solutions (formerly the Pew Center on Global Climate Change), and a number of leading scientists, engineers, and politicians. These calls speak to the potential of nuclear energy technologies to deliver large amounts of low-cost energy. New advanced reactors, small-modular reactors, and fusion are all candidates for providing this energy, with knowledgeable and ardent supporters backing each of these technologies and pathways.

At the same time, there are very serious concerns with both the nuclear power industry as it has developed thus far, and with how it might evolve in the future. Alan Robock of Rutgers University summarizes these concerns in an exceptionally clear editorial piece (Robock, 2014), where he questions the ability of the nuclear power industry to meet needed standards of: 1) proliferation resistance; 2) the potential for catastrophic accidents; 3) vulnerability to terrorist attacks; 4) unsafe operations; 5) economic viability; 6) waste disposal; 7) impacts of uranium mining; and 8) life-cycle greenhouse impacts relative to ”renewables.” Battles back and forth between proponents and detractors are sure to continue, but simply looking at #5 on this list alone – the direct costs and opportunity costs of investing in present-day nuclear power–demonstrates the scale of the challenge.

To address this, consider that of the 437 nuclear plants in operation worldwide today, most will need to be replaced in the coming three decades for nuclear power to even retain its current generation capacity, let alone to grow as a major technology path to address climate change. To examine this future, my students Gang He and Anne-Perrine Arvin (2015) and I have built a model of the entire Chinese energy economy, where nuclear power is expected to play a major role.

Today, China’s power sector accounts for 50% of the country’s total greenhouse gas emissions and 12.5% of total global emissions. The transition from the current fossil fuel-dominated electricity supply and delivery system to a sustainable, resource-efficient system will shape how the country, and to a large extent, the world, addresses local pollution and global climate change. While coal is the dominant energy source today, ongoing rapid technological change coupled with strategic national investments in transmission capacity and new nuclear, solar and wind generation demonstrate that China has the capacity to completely alter the trajectory.

The transition to a low-carbon or “circular” economy is, in fact, the official goal of the Chinese government (SI-S2). In the U.S.-China Joint Announcement on Climate Change, China is determined to peak its carbon emission by 2030 and get 20% of its primary energy from non-fossil sources by the same year. The challenge is making good on these objectives. Installed wind capacity, for example, has sustained a remarkable 80% annual growth rate since 2005, putting China far in the lead globally with over 91 gigawatts (4% of national electricity capacity) of installed capacity in 2013 compared to the next two largest deployments, namely 61 gigawatts (GW) in the United States (5% of total electricity) and 34 GW in Germany (15% of total capacity).

China’s solar power installed capacity has also been growing at an unprecedented pace. Its grid-connected installed solar photovoltaic (PV) capacity has reached 19.42 GW by the end of 2013 (1.6% of total capacity), a 20-fold increase of its capacity in four years from 0.9 GW in 2010. These figures show that rapid technological deployment is possible.

Central to this discussion is the role of nuclear power, because half of all the new nuclear power plants planned by 2030 worldwide are forecast to be built in China (roughly 30 of 60 total nuclear plants anticipated to be constructed over the next 15 years).

The question remains whether this large-scale build-out of nuclear power will happen a) in China; and b) as a significant component of the energy mix in other nations, both industrialized and industrializing.

In our modeling work on both the Chinese and United States energy economies (see the program website:, we find that there is a diverse range of pathways that can achieve the needed 80% emission reduction by mid-century. Some are more solar-dominated (Mileva, et al., 2013), some more wind-driven, some heavily reliant on biological carbon capture (Sanchez, et al., 2015) and so forth. A carbon price of $30 – 40 per ton of carbon dioxide is critical to drive each of these cases, and nuclear is no exception.

Returning to the list of challenges that Alan Robock poses, however, the prospects for nuclear power as a major source of energy are troublesome. This path is contingent on solving a very long and serious list of issues that most energy planners would conclude, at least at present, has not been successfully addressed.

Dr. Daniel M. Kammen is a professor in the Energy and Resources Group, and in the Goldmen School of Public Policy, and in the Department of Nuclear Engineering, and is the Founding Director, Renewable and Appropriate Energy Laboratory ( at the University of California, Berkeley.

References in the Article here.