Friday, February 14, 2014

Fusion in 30?:

What the "Breakthrough" Means

It was interesting, in more ways than one, to read some of the coverage of the recent news from the fusion research community.  The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) in California announced in the journal Nature that they had used lasers to compress a pellet of fuel and generate a reaction in which more energy came out of the fuel core than went into it.

This was indeed a significant breakthrough--though still, by the admission of most of the community, a long way from a practical way to generate energy.  Most researchers and others described it that way.  Science, the journal of the American Association for the Advancement of Science (AAAS), titled their article on the achievement, "Baby Steps on the Road to Fusion Energy."  Other articles, and many quotes in those articles, agreed both that this was a significant breakthrough, and that much more still needed to be done.

One spokesperson, however, appeared considerably more optimistic.  The Washington Post quoted Stewart Prager, director of the Princeton Plasma Physics Laboratory, as saying, "In 30 years, we’ll have electricity on the grid produced by fusion energy — absolutely."

That got my attention big time.  Why?  Because when I was in graduate school--more than 30 years ago--people were saying EXACTLY the same thing.  Fast forward to 2014.  No fusion energy.

To be fair, Prager's quote was the only quote I've seen that said that.  Everyone else expressed caution.  The Washington Post article itself reported several of those cautious statements.  Other publications did as well:  This is a "baby step."  There is a factor of 100 to go.  There are still a lot of hurdles ahead.

Even Prager really undercuts his own prediction, saying, "I think the open questions now are how complicated a system will it be, how expensive it will be, how economically attractive it will be."

In the real world, those are the key questions that distinguish a successful demonstration from a marketplace success.  So it seems that Prager does understand that there are going to be economic hurdles on top of the technical ones.  But even if he meant to say only that there could be fusion-generated electricity available in 30 years, he seems to be way ahead of most of the fusion community.

Optimism is good for people working on the development of a challenging technology, and we can all hope that, in 30 years, we will have more and better energy supply options of all sorts available to meet our needs for power.  And maybe things are really different now than they were 30+ years ago. 

However, in the meantime, the research community needs to be aware that the one sound bite that is likely to be remembered is the dramatic one.  And if it happens to be sound bite that has already been around for 30 years, it is even harder to convince anyone that things are different this time around.

I only hope that I'm around in 30 years to see if, this time, the prediction was true.

February 15 addition:  I have just found an interesting analysis of the energy dynamics of the experiment at NIF suggesting that the achievement is still far from breakeven when the full energy chain is considered.  It points out that the "net energy" was calculated only based on the energy absorbed by the pellet compared to the energy emitted by the resulting fusion action.  However--and this is a big however--the energy used to power the lasers was 28,000 times the energy generated.  This number illustrates the magnitude of the task that still lies ahead before we can even achieve a system that can really produce more energy than it requires to operate it--much less, do so on a commercially viable basis.


1 comment:

  1. There is NOT a factor of 100 to go. There is a factor of 25,000 to go, at least for fusion of this type. And considering that it's taken them decades to get this far, I don't see at all how they can get there with inertial confinement. It was an interesting idea, but it didn't work, and this "result" (tailored more for continued grant funding than for actual energy) doesn't change that.