Nuclear Power and the Road to Fusion

I think nuclear power is one of the most promising energy resources available to us, and I find the renewed interest in it encouraging.

Not simply because of what nuclear power can do for us today, but because of what it might eventually become.

There is a tendency to look at a technology as it exists today and assume that this is more or less what it will always look like. Nuclear power plants are enormous, complicated, and expensive, so we tend to imagine that nuclear power will always require enormous, complicated, and expensive facilities.

But that isn't generally how technology develops.

Consider the transistor.

The first practical transistors were relatively large, individually manufactured devices. Today we manufacture microscopic transistors by the billions on a single chip. That didn't happen simply because someone invented the transistor and then waited seventy years. It happened because transistors were useful.

So we used them.

Because we used them, companies invested in them. Engineers improved them. Manufacturing techniques improved. New materials were developed. Costs came down. Reliability went up. Smaller and more efficient transistors made new products possible, and those new products created still more demand for better transistors.

Obviously, a nuclear reactor is not a transistor. I'm not suggesting that nuclear reactors will follow Moore's Law until we have one sitting next to the lawn mower in the backyard.

The point is what happens when we actually use a technology.

If we continue building and operating nuclear power plants, we need nuclear engineers. We need physicists and materials scientists. We need companies capable of manufacturing specialized components. We need universities teaching nuclear science and engineering. We need research into reactor design, materials, radiation resistance, heat transfer, power conversion, and dozens of other related technologies.

And, perhaps most importantly, we have a reason to spend money on all of those things.

If, instead, we decide that nuclear power is something from which we should retreat, that entire technological infrastructure begins to diminish. Fewer reactors mean less demand for nuclear engineers, fewer companies investing in nuclear technology, less manufacturing experience, less research, and eventually less political justification for spending large amounts of money advancing nuclear science.

That brings us to fusion.

Fission does not somehow become fusion. They are fundamentally different nuclear processes, and practical fusion presents an entirely different collection of scientific and engineering problems.

But I think it would be a mistake to believe that our willingness to pursue one has nothing to do with our willingness to pursue the other.

A society actively using nuclear energy, educating nuclear engineers, developing advanced materials, building reactors, maintaining a nuclear manufacturing industry, and investing in nuclear research is much more likely to have both the resources and the political willingness to pursue fusion seriously.

And once practical fusion is achieved, that shouldn't be regarded as the end of the story.

It will be the beginning.

The first commercially practical fusion reactor will almost certainly not represent the ultimate form of fusion power any more than the first transistor represented the ultimate form of electronics.

Once engineers have something that works, they start asking different questions.

Can we make it cheaper?

Can we make it more reliable?

Can we make it more efficient?

Can we make it easier to manufacture?

And, inevitably, can we make it smaller?

Fusion has an extraordinary amount of potential energy available from a relatively small quantity of fuel. The problem isn't finding enough energy in the nuclear reaction. The problem is all of the machinery currently required to create, contain, sustain, and extract useful power from that reaction.

Those are extraordinarily difficult problems.

But they are problems we can work on.

I don't expect anyone to install a fusion reactor in the basement anytime soon. I don't expect a neighborhood fusion reactor to appear next to the community swimming pool in twenty years.

But what about fifty years?

A hundred?

Could advances in superconductors, materials science, plasma control, power conversion, manufacturing, and reactor design eventually produce fusion systems vastly smaller than the experimental machines we build today?

Could we someday reach the point where a fusion power source capable of supplying an entire neighborhood is contained in something approaching the size of a backyard shed?

I don't know.

Perhaps there are physical or economic limitations that will make that impractical. Perhaps fusion will always make more sense as a large, centralized source of power.

But we will never discover what the mature form of a technology looks like if we abandon the technology before it has a chance to mature.

That is why I think continued development of fission power is important even if fusion ultimately becomes the nuclear energy source we really want.

Fission gives us useful energy today. More importantly for the future, it keeps nuclear science alive as an active technology rather than merely an academic subject. It maintains the engineers, researchers, manufacturers, infrastructure, investment, and public familiarity from which the next generation of nuclear technology can grow.

If we want to know what nuclear power might look like fifty or a hundred years from now, the best way to find out isn't to stop building it.

It's to use it.