But something is better than nothing and some recent research revealed at the International Atomic Energy Association's Fusion Energy Conference in San Diego may be worth getting excited about.
You've all heard of fusion and likely give it a bad rap, for good reason. If you lump it in with the cold fusion nonsense that got mainstream media hype a while ago, it's understandable to be skeptical about miracle energy. Energy activists also dislike fusion, to go with their dislike of natural gas, hydroelectric power, wind power, current nuclear power and anything else more advanced than the 13th century. Why? Because fusion is not perfect today and, in their fundraising brochures, it adds to their arsenal of claims that scientists are out to kill us all.
They are basically correct about one part. Fusion is not ready yet. It may be another 50 years before it is ready. But, as much as it will send some in the broad audience into hysterical shrieks to read it, we have that 50 years and it will be time well spent. CO2 from energy companies have plummeted and the dirtiest source, coal, is in steep decline and producing levels of emissions not seen since Reagan was in his first term. Our current energy is getting cleaner and nothing else is ready to take its place - we'd need to build a nuclear plant every day for the next 50 years to meet our energy needs and even then we can do it only because fission energy is relatively efficient; if we instead tried to use solar power, the environmental energy darling du jour, it would be close to impossible. The 'greenmail' and environmental lawsuits that appear every time a decent-sized solar plant is even proposed makes it too flaky in a nation that wants a reliable energy plan.(1)
Politicians think about 'the now' and fusion is not exciting people, despite its potential. Like solar power, it's already been promised for 60 years and made no huge advances. If a president comes into power who is a believer, it may get tens of billions of dollars in subsidies thrown at it, like solar power has, but here on Science 2.0 we would still ridicule it because you can't just throw money at a company or a school and have a basic research miracle spring to life. It takes time, and mistakes, and increments, before anything revolutionary happens.
Instead of invoking yet another Cold War military-industrial pipe dream - government loves to build "Manhattan Project of X" behemoths despite none of them working since the actual Manhattan Project - a smaller, nimbler, 21st century way of doing science makes more sense when it comes to fusion. Lots of programs that are outside Big Science may lead to a real breakthrough and aren't 'all or nothing' financially. It's being done now, in both corporate- and government-funded science, and one recent program may be worth getting excited about.
Recent Fusion History: In Brief
In 1991, the Joint European Torus (JET) experiment produced produced a fusion reaction using deuterium and tritium and got 1 Mw of power for 2 seconds. It wasn't much, especially after 40 years of tinkering with fusion, but fusion as a 'hey, let's recreate the power of the sun under laboratory conditions' concept turned out to be so difficult it wasn't even known what the obstacles would be until they came up. Basically, the fundamental science of plasma had to be figured out to even start on the science of fusing ions in plasma under extreme heat. In 1995, The Tokamak Fusion Test Reactor at Princeton produced 10.7 million watts of controlled fusion power. We've had more incremental advances since then and in the south of France is ITER, a joint experiment of the US, the EU and five other countries that has a goal of producing 500 million watts of fusion power for 500 seconds by the end of the next decade, which would power about 150,000 homes.
Nice, but still not anything to get excited about 15 years from now, except for the fact that little advances in energy can lead to big ones. Fusion involves million-degree plasma and containing that takes more energy than it generates and energy density and efficiency are the entire point of fusion. A new piece of technology was recently discussed that could help contain the plasma using one percent of the energy currently required, which makes fusion not just fun but energy effective.
The coolest coffee cup ever? No, a computer drawing of a prototype which uses current-carrying handles to contain the plasma. Credit: T. Jarboe, Univ. of Washington
Fusion is primarily researched and implemented using magnetic confinement or inertial confinement. A tokamak reactor like ITER will have a container, a 'bottle', made of magnetic fields and plasma of 100-million-degrees. You can imagine the magnetic fields it takes.
"That method works but it's extremely inefficient and expensive, to the point that it really is a major problem with magnetic confinement." said Professor Thomas Jarboe from the University of Washington, who presented his latest work at the IAEA meeting. Jarboe and a team have been working on what they call helicity injection. As they describe it, spirals in the plasma produce unbalanced currents that generate the right electric and magnetic fields to heat and confine the contents. There was still a big problem with their method; while needing a lot less energy, it was unstable. If the conditions changed, it could wobble out of control and in production that would mean a reactor shutdown.
"We would drive it until it was unstable," Jarboe said of his approach. "Like you twist up a rope, the plasma twists up on itself and makes the instability and makes the current drive."
Their new proposed solution is to alternating the current through the handles in the prototype shown above, which produces the asymmetric magnetic fields that contain the plasma. The two handle-shaped coils alternately generate currents on either side of the central core, what they call imposed dynamo current drive. In their small-scale tests the plasma is stable and the method is energy-efficient and next they want to work with a larger reactor to see if it can maintain a sufficiently tight magnetic bottle.
"Here we imposed the asymmetric field, so the plasma doesn't have to go unstable in order for us to drive the current. We've shown that we can sustain a stable equilibrium and we can control the plasma, which means the bottle will be able to hold more plasma," Jarboe said.
So don't go looking for a Mr. Fusion to attach to your car just yet, there is still some work to be done, but we have plenty of time. As we learned from "Back To The Future II", that and hoverboards will not be in common usage until 2015 anyway.
NOTE:
(1) Berezow, Alex and Hank Campbell. Science Left Behind (pp. 73-74). New York: Public Affairs, 2012.
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