Thursday at their press conference on nuclear energy at COP 21, well-known climate scientists Drs. Jim Hansen (formerly NASA, now Columbia University), Ken Caldeira (Stanford University), Kerry Emanuel (MIT) and Tom Wigley (Adelaide University), presented and discussed what they called their stark (energy) challenge.
The presentations of their proposal were short (as their position had been submitted in a media alert prior to the conference) and overall unconvincing. It is clear that there is an “increasing urgency of fully decarbonizing the world economy”. But they didn’t show persuasively, in my view, that “renewables alone cannot realistically meet the goal of limiting global warming to 2 degrees C, and that a major expansion of nuclear power is essential to avoid dangerous anthropogenic interference with the climate system this century”. They didn’t demonstrate why huge financial resources and few decades should be devoted to developing the fourth generation (light-water) nuclear reactors, as they are recommending, while we know time is of the essence in solving the climate problem and funding essential to bringing to market already available (renewable) technologies.
With little technical information about the new nuclear technology they are advocating, much of the press conference was a rhetorical exercise against renewable energy. They mentioned the technical problems of intermittency and lack of adequate storage capacity. However, they failed to indicate that when solar, wind and water are combined the intermittency issue is essentially eliminated. Also, much research has been happening on the storage side so that new solutions are gaining ground.
Their analysis of the work of Mark Jacobson from Stanford was the most troubling aspect of this press conference because of its lack of scientific backing. Mark is the long-term recognized expert in the assessment of renewable capabilities to replace fossil fuels. He has published in the reviewed literature how it would be technically feasible to scale up renewables to 80% of the global energy mix by 2030 and 100% by 2050. Kerry Emanuel, a world leading expert in tropical cyclones, differed from Jacobson’s point of view, arguing that “the numbers don’t up add unless you put nuclear power in the mix”, suggesting that he had done the computations; he had done the math. Ken Caldeira had a similar view position. While he would like to see the world powered by renewable by mid century, he doesn’t believe it to be possible. It is, however, Tom Wigley who was the most critical without substantiation with: [Jacobson’s work] “is seriously flawed in many areas”.
Ken Caldeira started from a moderate position, recalling that many years ago he used to demonstrate against nuclear power and had even been arrested for it. Despite this, he presented the best articulated support for nuclear energy. After indicating that the magnitude of the problem is so huge that we can’t leave any technology out of the discussion, he argued that we must have a technology-neutral, level playing field in energy with an appropriate regulatory environment and appropriate cost competitive market. He emphasized the point made on several occasions by the group that we must not leave any technology off the table. And in his view, only one technology can bring energy when the sun is not shining and the wind is not blowing and that is nuclear energy. Then he started bringing up astonishing arguments against renewables. First, answering a question he stated that renewable doesn’t mean good. He went on noting that we want technologies that have a small environmental footprint. But many renewables have large footprints. As we want to leave room for nature, we must make our technology as compact as we can. The deployment of renewables like solar panels or wind turbines covers a lot of real estate. As a journalist called him on his apparent anti-renewable position, he fervently denied it.
Jim Hansen, the person we all respect for taking an early position in the fight for climate when few voices were being heard about 25 years ago and for all his leadership over time through various actions, also strongly advocated for nuclear energy. Jim arrived in the venue very confidently like a new kind of rock star, followed by a horde of journalists, surrounded by several TV camerapersons. At the outset of his talk, he presented the climate risks he knows so well, going on to a little story about his grand son’s emotions about the changing climate. When asked by a journalist from South Africa about the significant CO2 emissions associated with the production of nuclear power through its life cycle, he responded that nuclear energy had essentially no carbon footprint. Clearly prepared for that question, he (and others later) quoted the number (15 g/kWh) included in the last IPCC report. But, according to Jacobson (NPR on point interview, Dec 3), this is a number provided by the nuclear industry and disavowed by two scientific reports since. Some climate scientists and many young activists support Jim’s climate fight and all, like him, are concerned about the life of their grandchildren if we don’t address the climate problem. However, they do not necessarily champion his position about nuclear energy.
How will the climate community react to this press conference advocating nuclear energy in the name of solving the climate problem in such an important venue? These four scientists might have been at COP21 as citizens. In fact, they were not invited to talk in the main official conference venue in the “blue zone”. Nevertheless, they took advantage of their position as experts in their field to express their ideas and position about nuclear energy in front of many cameras and microphones. So, in the end, they could be seen as representing a community of their peers. Only a few peers were in the audience listening. Jim mentioned talking with some of them, but no serious statistics are available on the prevalent position of climate scientists. A couple journalists tried to argument with the presenters through questions but were harshly rebutted.
Many important concerns about nuclear energy (e.g., waste, accidents, dismantlement costs) were not addressed in this press conference. Well researched and documented arguments against the position presented here have been published in the scientific literature. A point that can be made here is that when having a press conference led by four climate scientists, there might be an assumption that they represent a constituency of peers. One could argue that this might have been the overall intention of the group. Otherwise, Jim Hansen could easily have come alone since he has enough notoriety to bring a crowd to listen to him.