Nuclear Energy and Carbon Reduction:

A Critical Combination

I was pleased last week to have the opportunity to attend two events associated with the official rollout of a recent MIT study entitled, "The Future of Nuclear Energy in a Carbon-Constrained World."  This was an interdisciplinary study involving a number of people, both at MIT and elsewhere, some as part of the study group, and others as an advisory committee and a team of reviewers.  The co-chairs of the study were:  David Petti (also the executive director), Jacopo Buongiorno, Michael Corradini, and John Parsons.  

This study is part of a series of studies that MIT has conducted, starting in 2003, on a variety of energy related subjects, including geothermal power, coal, natural gas, solar power, and the electric grid.  Several of the previous studies dealt with nuclear-power related issues, but this one had the unique twist of focusing on the implications of nuclear energy in a future where there are constraints on carbon generation.

The first meeting of the day was held at the headquarters of the American Association for the Advancement of Science (AAAS), and the second event was a meeting of the MIT Club of Washington, DC.  The 2 programs featured most of the same speakers, so I worried that I might be bored by the second round, but that was far from the case.  The study provided a very thorough and comprehensive look at the energy supply options under a variety of assumptions, both in the US and around the world, so there was a lot to digest.  In fact, having listened to a summary of the study twice, there is still a lot more detail in the very comprehensive report linked above.

But if I could highlight one really dramatic visual take-away from the presentations--and the study--it is a graph projecting the likely cost of generating electricity under different levels of carbon restrictions and different assumptions about nuclear power.  In particular, Figure E.1 in the executive summary, below, shows that the cost of generating electricity is significantly higher for scenarios of very low carbon emissions if nuclear power is not part of the mix, both in the US and in China. 

 

Figure E.1 

 

The irony is that, the same week that I was attending these briefings, I received multiple messages regarding an initiative of a group in my home state of Maryland who are trying to gather signatures for a letter to the Maryland government urging the government to adopt a low-carbon goal for the future energy supply--but never mentioning the importance of nuclear power in doing so effectively.  When I contacted them to ask about this omission, they claimed they were not anti-nuclear, but wanted to avoid a controversial subject. 

I haven't been able to get my arms around the logic--highlight the problem, but don't mention the one option that is likely to be critical to a realistic solution.  It seems to me that this is a recipe for failure in one way or another.  And this is graphic evidence that the message about the important role nuclear power needs to play in the future still isn't fully recognized and considered in the ongoing dialogue.

So I congratulate the entire team of the MIT study for a job well done, I urge everyone to review the study, and I encourage people around the country--and the world--to share the important findings of the study with their elected officials and others so that we end up with carbon-reduction strategies that are realistic and effective.

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All of the Above:

A Matter of Common Sense

One recurring discussion we seem to face is what the mix of energy sources should be.  This discussion has become particularly important as the drive to reduce carbon emissions grows, and as the costs of renewable energy simultaneously seem to be plummeting.  That combination of factors has tempted some to envision a world powered entirely by the sun and the wind.

Many of us in the energy field have long tried to challenge such a scenario.  Experience has taught us that new problems often emerge as the use of a technology increases.  I recall many years ago reading a "look back at history" type of article that lauded the fact that those newfangled automobiles would solve the pollution problems created by horses in the city.  No one recognized then that automobiles would bring another type of pollution, and that, years later, we would spend time, money and energy to address that pollution.

Therefore, I was very pleased to see a very rational discussion of the issue entitled The Environmentalist Case against 100% Renewable Energy Plans.  The article draws a distinction between what is technically possible and what is optimal, thus transforming the argument from whether or not something can be done to whether it should be done.

The article also takes on the difficulty of achieving a 100% renewable power supply.  Although proponents of such a scenario cite various storage possibilities (as well as grid interconnections), the article points out that energy storage is not just a daily problem.  Wind patterns are seasonal, and there can be extended patterns of wind variability for other reasons.

In fact, shortly after I read this article, I saw some statistics from the Energy Information Administration (EIA) that graphically showed a 5-month period at the beginning of 2015 where the capacity factors of wind plants on the West Coast were lower than the average of the previous 5 years.  The EIA notes that capacity factors vary non-linearly with wind speed, so small decreases in wind speeds can result in much larger changes in capacity factors.

As a result of these variations, a huge investment in storage would be required in order to assure a reliable energy supply during extended periods of low wind speeds.  Yes, wind and solar mixes can complement each other, and yes, grid interconnections can bring renewable-generated electricity from far away, but each of these scenarios has costs and limitations as well.  Reliable baseload sources can do the same job much more efficiently.

The article also takes on some of the other, less technical, issues.  In particular, it notes the irony that eliminating nuclear power in favor of wind and solar energy requires much more transformation of the landscape to produce the same amount of energy, which draws opposition from other environmental groups, as well as from people who don’t want wind turbines marring their scenic views.

The article raises other points as well.  For example, it notes that all energy technologies are evolving, so the projected benefits of advanced solar or wind systems should be compared to the those of advanced nuclear systems and advanced carbon capture and storage systems, not to present technologies.  This is a point that I have found is often glossed over--by proponents of all technologies.

There are probably other points that the article could have made.  It comments on the small footprint of nuclear power plants compared to wind and solar plants, but not on the greater amounts of materials needed for renewable plants producing the same amount of power, and the environmental impacts of mining and manufacturing those.  Or of the need for specialized materials such as rare earths.  It mentions an allegation that mining uranium is energy intensive (and therefore, generates carbon at the front-end), but it doesn't challenge that assumption or compare the front-end energy demands with those for renewable energy sources.    

The article emphasizes that replacing some non-emitting sources with other non-emitting sources gains nothing environmentally, while adding a lot to the cost.  It concludes that the best option is a mix of energy technologies, noting that the optimal mix may vary, depending on location. 

In summary, the article makes a good start at looking at our energy mix holistically.  In particular, it helps make the case of why something that is technically possible (maybe!) is not necessarily the best path to pursue, and suggests how we should be approaching decisions on our future energy supply.

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