Saturday, September 18, 2010

Post # 21: Imperative 3 – Enable the transition away from fossil fuels

Today, approximately 40% of our nation's carbon emissions stem from the use of fossil fuels in the transportation sector (principally liquid fuels production and consumption), and industrial sector (principally fossil-derived process heat production).  Indeed, my own model indicates that even if we completely decarbonized our electricity production, by mid century our total national carbon emissions would drop by less than 25%!

Imagine that!  If not one kilogram of carbon dioxide was released in the production of electricity in 2050, we still would only achieve modest reductions in overall greenhouse gas (GHG) emissions.  Why?  If the population continues to grow at a modest 0.6% per annum, and all these people still drive automobiles, and we still move freight across our country in the same manner, and still provide process heat to our factories in the same manner, we are only addressing 60% of the problem when we focus on electricity production and use.

Improvements in the efficiency of production and use of electricity are already effectively accounted for in my simple analysis.  So, the only way to further improve our lot and achieve more-sizable reductions in our GHG emissions is to transform the transportation and process heat sectors.  We must reduce the consumption of petroleum in our vehicles and the use of oil, coal, and natural gas for production of industrial process heat.

Thus the challenged posed by President Obama's goal of an 80% reduction in carbon dioxide emissions is daunting - to say the least.  In fact, I feel confident in saying the Administration's goals for greenhouse gas emissions reductions are virtually impossible without a revolutionary change in our society.

There are many who believe these energy challenges will drive almost unimaginable changes in population distribution. Interestingly, opposing arguments can be made with regard to the direction of these changes.  Some who have studied this issue believe we will see a massive centralization of our population in urban centers to reduce the transportation costs and petroleum consumption associated with daily commutes to work.  Others feel the opposite will happen – that things will become so dire, our socio-economic infrastructure will collapse, resulting in a return to an agrarian economy.  This belief is normally associated with the assumption there would be a mass exodus from population centers into the suburbs and country side.

There is another solution with five ingredients:
  1. Electrification of the private vehicle and over-road freight transportation sectors (probably requires a major breakthrough in battery technology);
  2. Switching to synthetic fuels where vehicle electrification is not possible;
  3. Switching away from fossil-derived process heat in industrial sectors (especially the petro-chemical sector);
  4. Increasing the size of the nuclear electric power plant fleet and improving the electric grid as necessary to deliver the electricity required for # 1; and
  5. Developing and deploying a new generation of high-temperature and very-high-temperature nuclear reactors to provide the process heat needed to enable # 2 and #3.
This "simple" formula – electrify the transportation sector and produce the electricity with nuclear power plants, and switch to nuclear-derived process heat across our major industrial sectors – would enable the continuation of life as we know it in the western world.  I am not aware of another strategy that is as practical and easily implemented as this approach.  Frankly, absent this approach, or something very similar to it, things look pretty grim...

Just thinking...

Sherrell

3 comments:

  1. Sherrell,

    We think alike. Here's my 10 minute presentation to the BRC. I'll be giving a 60 minute talk here in Hanover Friday.
    http://www.slideshare.net/robert.hargraves/hargraves-lftr-aimhighbrc

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  2. Very interesting presentation, Robert.

    Both molten salt fueled, and liquid salt-cooled (fluoride salt cooled reactors) show great promise for addressing a variety of high temperature process heat and fuel cycle needs. As you know, there are a number of materials challenges for systems operating at or above 700 deg. C that need to be addressed for both systems.

    The connection between abundant, affordable electricity, and quality of life is very real. Competition for global fuel resources of all types will only increase throughout this century. Growing scarcity of resources will compromise the foreign policy, national security, economic prosperity, and domestic tranquility on any national that lacks command of it's energy supply. Let's hope the U.S. doesn't fall into that category...

    Thanks for the comment.

    Sherrell

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  3. Sherrell,

    I know I won't change your mindset very easily but I'd caution against the drive towards temperatures above 700 C for either molten salt fueled or molten salt cooled designs. I think everything you want to do, except a few industrial processes, can be accomplished with 700 C outlet temperatures.

    Yes thermal efficiencies can go up somewhat but at a high materials R&D price. Besides that, Supercritical CO2 or Ultra Supercritical water are the best current choices and neither wants anything much above 600 C anyhow.

    Hydrogen production by the copper-chlorine process that only requires 550 C is overtaking sulfur-iodine in many peoples opinion. Many other liquid synthetic fuels are possible with more modest temperatures or of course just with electricity.

    At my recent visit and talk at ORNL Jess Gehin set up some great round table discussions and I certainly got the impression that getting to 800 C and then onto 1000 C seemed almost an obsession. My advice, slow down, relax and enjoy good old Hastelloy N at 700 C!

    If you missed my talk on molten salt fueled designs and are interested, it is available through the ORNL NTPO site

    http://www.ornl.gov/sci/ees/ntpo/presentations/

    David LeBlanc

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