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Nuclear Power at a Crossroads

By Felix König (Eigenes Werk (own work) – Samsung S750) [GFDL or CC-BY-SA-3.0], via Wikimedia Commons
Building a sustainable energy future is going to take a lot of compromise. Among the sources of energy which I think are often mischaracterized by both proponents and opponents are nuclear power plants.

On one hand, many on the so-called environmental left do have a point in that nuclear power plants can be unstable and lead to dangerous leaks. The recent trouble with the San Onofre plant in California, the news that the nuclear waste units at Hanford are leaking (and actually may be too dangerous to even clean up), as well as the terrible fallout from the Fukushima disaster certainly lend credence to this thinking. Further, it should be no secret that the mining of uranium involves exploitation and environmental destruction of the poor countries in which most of the world’s fissile ore is found.

On the other hand though, I think that many on the environmental left fail to consider the huge positive impact that nuclear power could have on global warming and climate change. Nuclear fission does not produce any direct carbon emissions (the “smoke” rising from the cooling towers is actually steam, water vapor). The positive impact of near-zero airborne pollutants is huge.  For example, a recent paper published by the ACS1 highlights the advantages in clear terms:

Pushker A. Kharecha and James E. Hansen state that nuclear power has the potential to help control both global climate change and illness and death associated with air pollution. That potential exists, they say, despite serious questions about safety, disposal of radioactive waste and diversion of nuclear material for weapons. Concerned that the Fukushima accident in Japan could overshadow the benefits of nuclear energy, they performed an analysis of nuclear power’s benefits in reducing carbon dioxide emissions and air pollution deaths.

The study concluded that nuclear power already has had a major beneficial impact, based upon calculations of prevented mortality and greenhouse gas emissions for the period 1971-2009. Nuclear power could prevent from 420,000 to 7 million additional deaths by mid-century, and prevent emission of 80-240 billion tons of the greenhouse gases linked to global warming, the study found. “By contrast, we assess that large-scale expansion of unconstrained natural gas use would not mitigate the climate problem and would cause far more deaths than the expansion of nuclear power,” it notes.

The positive effects of near-zero emissions has a huge impact, both historically speaking and looking forward. Lifecycle greenhouse-gas emissions for nuclear are far lower than the energy sources we typically use (orders of magnitude lower, in the case of coal and even natural gas), and are actually comparable with photovoltaics2. Another notable advantage to nuclear power include the amount of power produced for near-zero emissions, on the order of 3000 MW (compared to 50 MW for a typical solar farm and about 350 MW for a typical wind farm). This value is generally higher than for even carbon-based natural gas (1000 MW) and coal (2500 MW) power plants as well3.

A standard utilitarian outlook will demand the follow-on question: Are the benefits worth the risks? However, I think this is the wrong question, because it assumes a static, linear type of world. The fact is, an overwhelming majority of the scientific community, and most reasonably-minded people, agree that we need a huge reduction in the amount of greenhouse gases that we currently emit. That said, no one really wants to destroy the environment, exploit poor countries, and create unstable systems. I think better questions might be:

  • How can we reduce the negative impacts of nuclear fission energy through technological and sociopolitical means?
  • Can we require energy companies to make a greater investment in safety technology for reactors?
  • Can we form coherent and sensible strategy for the storage and containment of nuclear waste?
  • Can we regulate the atrocious behavior of multinational energy corporations as it pertains to exploited countries, forcing them to comply with stricter (and therefore more expensive) controls?
  • What feedback-loop impact do the answers to the above have on the original constraints?
  • What percentage of our total energy portfolio should be sourced from fission?

I think that last question also gets at another perspective often missing from the debate — that solutions are seldom either-or. I suspect that neither “no nuclear power” nor “all nuclear power” will ever be a reasonable sustainable solution to our energy problems. As the present generation of reactors reaches design age and the construction of new reactors become mired in political hurdles, these decisions and tradeoffs need to start getting made in a clearheaded and reasonable way soon.

In the near to mid-term, I think nuclear absolutely will have to be on the table as part of the portfolio that gets us to a long term solution. Despite it’s temporary advantages, in the long run we will have to come to terms with the constraint that nuclear fission, just like hydrocarbon energy, relies on a finite resource: uranium and plutonium ore, which are extracted from the ground just like oil and gas. In this sense nuclear fission’s key role may be simply as a bridge to get us by until research and development of photovoltaics, solar/geo thermal, space power, and especially nuclear fusion allow for these much more sustainable energy sources to overcome their present technological hurdles, and eventually take over.

Show 3 footnotes

  1. The full paper is by Pushker A. Kharecha and James E. Hansen (NASA Goddard Institute for Space Studies and Columbia University Earth Institute), Prevented Mortality and Greenhouse Gas Emissions from Historical and Projected Nuclear Power.
  2. See slide 18 of Edenhofer, O., The IPCC Special Report on Renewable Energy Sources: and Climate Change Mitigation“, UN Climate Change Conference June 2011.
  3. I like to link sources, but these didn’t come from one place. Since the variability of power output is very high, depending on the size of the plant, I had to make an eyeballed average of looking up several examples.


amprog:

Your cartoon of the day!

By Mike Luckovich
From the Cartoonist Group.

(Source: americanprogress.org)




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