Monday, June 22, 2015

Learning More About Energy Choices

If you have taken the time to read the paper that I wrote for EM443 in the fall of 1991, you will see that I had some pretty significant conceptual errors in my understanding of both turbo machinery and the politics and history of energy industry developments. I was definitely naive and had a lot to learn. Fortunately, I was in a great place to learn and had access to a world class university library.

I also began what remains a habit today - I started participating in on-line discussions using the handle of Atomic Rod. (Aside - just this past week I met someone for the first time who told me that she used to read my posts on USENET about atomic energy and that is part of the reason that she got interested in the field. That was a humbling experience and one that makes me realize that words do have meaning and impact.)

In the Naval Academy library there were several sections that focused on energy topics that included numerous shelves of books talking about nuclear energy from a variety of points of view. At one time, the Naval Academy had one of the largest nuclear focused engineering programs in the country under the title of Marine Engineering; by the time I was doing my research that program had nearly completely disappeared. It had been ten years since Rickover had retired, the 80/20 split (80 percent of the students in engineering and science majors, 20 percent in "bull" majors like History, English and Political Science) had gone the way of the dodo bird, and political science was the most popular major at the school.

For my purposes that turned out to be okay; there were plenty of good technical references from the days when the Marine Engineers demanded resources and there was a depth of coverage of the political debates that dominated the 1970s and 1980s.

Dr. Chih Wu - USNA's Alternative Energy Guru


I decided I needed some more depth to my understanding of energy topics in general, so I signed up for Dr. Chih (Bob) Wu's course in Alternative Energy. Dr. Wu was kind of a local celebrity; he had published a number of books including one on ocean thermal energy conversion. He was also quite a dynamic teacher.

One day, Dr. Wu and I had a conversation about his research interests. I knew he had started off in nuclear related fields and wondered why he had shifted to alternative energy systems. He explained that he never lost interest in nuclear, but that essentially all of the research money for nuclear power had disappeared by the mid 1970s and he had to do something to support his academic advancement. I knew that several of the professors did work for Naval Reactors, but Dr. Wu told me that was not an option for him because he wanted to publish his work.

After I had taken Dr. Wu's formal courses in Alternative Energy, I asked him to mentor me for an individual study research project. I am pretty sure that was an almost unique request - having a serving company officer as a research student at USNA - but Dr. Wu agreed. I learned a lot about conducting research and writing technical papers during that semester and owe a good deal to Bob's cheerful and questioning attitude, especially since I was working in an area that was somewhat outside of his usual academic interest areas.

As it turned out, Dr. Wu got interested in what I was doing and even worked with me on a published paper on the topic - my first ever published academic paper. (If you do not want to order the official published version, I have posted the advance copy with one of the reviewer's comments. I am still looking for the original article in the periodical - I have moved several times since 1993.)

(Update: June 27, 2009: Here is a link to a scanned PDF of the paper titled Nuclear Powered Gas Turbines: An Old Idea Whose Time Has Come that was published in the Proceedings of the IASTED International Conference August 5-7, 1992.)

Not Invented or Developed Here

During the same time that I was working with Dr. Wu, I made contact with several of the people who had published articles on high temperature reactors and gas turbine nuclear plants. Colin MacDonald from General Atomics was one of the most prolific authors on the topic with dozens, if not hundreds of papers published in various engineering journals. Richards T. Miller (CAPT, USN ret.) was another guy with whom I corresponded and whose papers I read with great interest.

Both of those gentlemen opened up a whole world of information to me about pretty well developed projects designed to take advantage of the steady heat that nuclear fission can produce by combining it with the steady, low cost flow that can be provided by modern gas compressors and used by modern turbines. In both cases, they warned me that my employer - the US Navy - did not have any interest in pursuing nuclear plants that were not steam plants. Both of them had received rather stern warnings from Naval Reactors about articles that they had published in various technical journals advocating the use of such machinery on board ships or submarines. I have included a copy of one of the notes that I received from Colin; I found it attached to a rather dusty paper.

During my recent digs through history files, I also found a letter to the editor from Richards Miller to the Naval Institute Proceedings written after I had left the Navy - the first time - and published my own article about using closed cycle nuclear gas turbines as the basis for future submarine propulsion plants. That, however, is getting a little ahead of the story.

My correspondence with those gentlemen and others like them helped me to answer one of the questions I had after writing my first paper - why was there such little information or development if the idea was such a good one? This is something that young, idealistic people often ask themselves when they find a great idea buried in a library or on a back shelf. Looking back through the lens of a bit more experience in the world, I have a bit more understanding of the real depth and logic behind a "not invented here" attitude.

Once an organization picks a path forward, they make a tremendous investment in that path, especially when it is something as complicated as not just one nuclear power plant but an entire fleet of them. Tooling, machinery, training programs, and supply chains are not easy to change. Attempting to change them can often result in what systems engineers call "hunting" which is a rather unstable condition that provides a lot of movement with little forward progress. Unlike a lot of people that have run afoul of NR's desire to keep control of their destiny, I get it and admire their continued success at refining the PWR steam plants that they invented rather than hunting for something better. That does not change my frustration with their efforts to slow down or halt others from thinking about new or different ways to capture and make use of fission heat.

So after learning that part of the challenge that had slowed closed cycle gas turbines was technical inertia, I continued digging to see if there were any technical challenges that had limited development. One of the other things that I have learned in researching successful and unsuccessful technology programs is that the unsuccessful ones often have a hard barrier to development that gets minimized in promotional materials prepared by boosters. The successful ones also have their challenges, but they have somehow managed an acceptable work around that could be implemented in time to allow commercial introduction and acceptance.

Areas for Technical Improvement


As I learned more about the closed cycle gas turbine proposals - and nearly all of the papers that I read were about proposed systems rather than real ones - I became convinced that the promoters just did not understand how difficult it was going to be to build and operate the machines that they drew on paper. Nearly all of them included multiple stages of heat exchangers for intercooling and recuperating, all of them proposed very high gas pressures, and nearly all of them proposed a control system that involved large pressurized storage tanks of gas that could alter the system pressure to alter its mass flow rate.

Based on what I had learned from my friends about combustion turbines, I realized that these proposed plants did not have the simplicity advantages shown by commercially successful gas turbines. Without some changes, it looked to me like closed cycle nuclear heated gas turbines were destined to remain on paper. I'll have to leave it here for now - time to go earn a living.